The Ford Bronco is already a hardcore off-road beast. Especially with its optional 35-inch monster-truck tires, the vehicle is tall, heavy, relatively noisy, not particularly agile in the corners, and clearly makes plenty of compromises to go toe-to-toe off-road with the legendary Jeep Wrangler. And yet, for reasons only those in Dearborn’s Glass House can tell you, Ford decided it needed to offer an even more hardcore version. It’s called the Ford Bronco Raptor, and it takes a vehicle that I thought could only possibly be made slightly more hardcore while remaining street legal, and cranks the intensity up so high it rips the dial right off. I crawled the widebody Bronco up a gnarly boulder-filled trail and then blasted 60+ mph over a makeshift racetrack in the desert, and I’ll tell you straight-up: I’m still in shock. The Ford Bronco Raptor is madness.
As some of you may know, I’ve been hitting off-road trails in Jeeps since I was just a young teenager. These experiences inspired me to get an engineering degree and work at Jeep, where I helped develop the JL Wrangler. I off-road my vehicles frequently, and oftentimes I destroy them in deep mud puddles. I mention this only to communicate where I’m coming from when I say things like “The Ford Bronco Raptor is madness.” It really is a tremendous feat of off-road engineering, and Ford was so confident of this fact that it sent journalists up some genuinely treacherous trails.
[Full Disclosure: Ford flew me to Palm Springs, California to show me what the Ford Bronco Raptor could do in the wide-open desert and on the boulder-filled trails of one of the world’s toughest off-road races: King of the Hammers. It’s likely that the sum of the prices of the two nights at the hotel and the meals the company bought me eclipsed the cost of my recently-acquired 2000 Chevy Tracker off-road beater. That’s right, two days of food and lodging probably cost more than my car; needless to say, I had to fake it ’til I made it (pinky up when drinking, use big words, talk about stock portfolios — I know how it goes).]
[Editor’s note: Nobody was fooled, David. – JT]
Before we get into my on and off-road driving impressions, we need to talk with some engineers about the hardware that makes the Bronco Raptor different from the ordinary Bronco.
A Look At The Hardware
If you’re familiar with how the Ford F-150 Raptor differs from the standard F-150 pickup, then you’ll probably have a good idea of what Ford did to the Bronco to Raptor-ify it. The body is wider by nearly 10 inches to stretch over broader axles; the tires are larger at 37 inches in diameter, making them the biggest-ever standard tires on any consumer-grade Ford; the suspension and steering have been been redesigned to take a beating off-road and to afford absurd levels of wheel travel; the shocks are fancy Fox Internal Bypass units meant to handle lots of plunging over uneven surfaces at high speeds; the engine is significantly more powerful at 418 horsepower versus 315 on the V6 standard Bronco; the exhaust is louder; the styling of the fascias and hood is also louder; and much of the vehicle has just been covered in skid plates and/or toughened up a bit to handle higher loads associated with bombing along a desert at ludicrous speeds.
Given that the Bronco Raptor is built on the base Bronco platform, which is already so capable, you may be wondering how much engineering actually went into the Raptor-ification process. Take the Bronco, modify the fenders a bit, add a small lift to fit the 37-inch all-terrain tires, and you’re good to go, right? Not quite. I spoke with Ford’s engineers to learn more about what went into turning the off-roader into a Raptor, and they basically broke the challenges they faced into three main areas: Packaging, handling (with “roll steer” being the primary topic of discussion), and durability/stiffness.
To get us started, we need to talk about one of the main differences between the Raptor and the non-Raptor Bronco: the dimensions.
Why The Huge Tires And Why The Wide Stance?
Big Tires To Protect The Hardware And Improve The Ride
There are some real functional benefits to that menacing stance beyond just badass looks. The big tires help for reasons that are probably fairly obvious: They increase ground clearance, as well as approach, departure, and breakover angles, protecting the vehicle’s vulnerable bits from rocks and bumps and inclines and anything the Bronco wants to drive over or onto.
Perhaps more importantly, those big tires improve ride quality over extremely harsh terrain; it’s not just that the huge sidewalls can flex to soften the blow of a rock in the middle of the trail, it’s the fact that, relative to 37-inch tires, that rock may as well be a pebble. The relative size of an obstacle to a tire’s diameter plays a big role in how much harshness that obstacle can impart on the ride, so those giant meats are there for a reason. Obviously, they’re heavier than smaller tires, and that has some negative handling implications, as the unsprung weight means the suspension can’t react as quickly to “follow” uneven terrain, but it’s a tradeoff, and one that — as I’ll discuss later — appears to have been a good one.
A Wide Track To Reduce Load Transfer, Fit Big Tires, And Allow That Suspension To Flex
Okay, so that’s a bit about why the Bronco Raptor is so tall; now let’s talk about width. There are a number of benefits of that ridiculously wide track. The obvious one is that it helps package the big tires (we’ll talk about packaging soon), but there are also dynamic implications. I won’t pretend that I’m an expert on these, since I was never a suspension engineer, but I do know that a wider track can help reduce load transfer, which is defined by the following equation:
A large track width is also important in facilitating the high suspension articulation that the Bronco Raptor needs to turn large rocks into fluffy pillows, and not just because the width helps package a big tire’s huge motion envelope. There are mechanical benefits of a wider track in aiding suspension flex; this is particularly important for vehicles with independent front suspension, and it’s one of the drawbacks that solid axle-diehards often tout.
The Ford Bronco is built on the Ford Ranger’s “T6” platform, so up front is an independent front suspension, which itself offers a number of handling benefits over a solid axle and makes it easier to package a rack-and-pinion steering setup (which is far more precise than a steering box setup found on solid axle vehicles). The suspension consists of two control arms — an upper and lower A-arm — hooked to, in the case of the Bronco Raptor, a modified version of the Ford F-150 Raptor’s steering knuckle.
When the wheel moves up and down over bumps, the control arms are pivoting/rotating about their mounts on the frame. In order to have lots of vertical wheel travel to absorb bumps, those arms have to swing quite a bit. This can be a bit of an issue, because at a certain point, the ball joints located where the control arms meet the knuckle will bind up; the same could happen at the ball joint between the tie rod and the knuckle.
Perhaps more concerning is the fact that the axle that sends power to the wheel also has to swing in an arc during suspension travel. As you can see in the image below, the angles of the CV joints that allow those axles/halfshafts to send power to a wheel that is both moving up and down over bumps and side to side during steering become quite steep as the suspension droops. At some point, the joints could bind up, and even if they don’t, their service lives are reduced when they run at a steep angle.
So how do you lift a vehicle (which itself causes the arms to swing), and build in plenty of additional suspension travel without causing issues with ball joints/CV joints binding or possibly failing too soon? Well, you lengthen the control arms. Basically, you want to maximize the length of the arc that the ends of the control arms sweep (since these arcs are related to overall up-down wheel travel) while minimizing the degrees those arms have to swing.
Since the equation for arc length is Arc Length (s) = radius (r) * angle swung (theta), you can see that to minimize the angle that the arms and axles swing while maximizing travel (s), you need to make the control arm (r) as long as possible. This is probably something you can visualize in your head.
The other reason for the high ride height and wide track width is packaging. Let’s get into that now, and then dive into the other packaging challenges that Ford faced.
Packaging
Thirty-seven inch by 12.5-inch tires are big. Hell, they’re humongous. And while your friend Steve probably has a set of them under his Jeep Wrangler JK, make no mistake: Packaging these things is difficult.
When automakers package tires, they build what’s called a tire envelope (at least, that’s what it was called at Chrysler; it looks like the one in the .gif above). A tire envelope is basically a virtual “blob” made using Computer-Aided Design software; it represents a tire’s full range of motion, both along the Z-axis (i.e. up and down during a bump) and about the Z-axis (i.e. during turning), plus it accounts for slop in steering and suspension parts (bushings, etc). I asked Ford if they could send me the tire envelopes for the Bronco Raptor, but they said no; I’m a little disappointed, because I bet they’re enormous.
Anyway, the point here is that shoving 37s on a car is not easy. And while additional ride height and track width to keep that big black blob away from the body and frame definitely help, Ford still had to get creative to make those big meats fit and to allow that suspension to travel 13 inches up front and 14 inches in the rear. One packaging challenge was the rear damper piggyback, which had to be angled “down” relative to the coilover in order to prevent the tire from rubbing against it when that side of the Bronco Raptor is “stuffed” (i.e. the suspension is compressed).
Also in the rear is a giant bend in the tailpipe to clear that bouncing, 9.25-inch ring gear-equipped Dana 50 rear axle:
Up front the control arms have been shaped precisely to clear not just parts of the body, but also the tire and spring:
Here’s a closer look at that inside bit of the control arm, where it has to avoid the spring:
And here’s the part of the body that necessitated that dip in the control arm:
Of course, the biggest changes that helped facilitate the massive tires and high-travel suspension were the SMC composite front fenders and rear quarter panels, which remain far away from the tires even when the vehicle is experiencing extreme suspension flex
Handling Challenges
So packaging was a big part of the Bronco Raptor’s engineering story, but there’s a lot more to the vehicle’s development than that. One thing that Ford engineers mentioned a lot was the concept of “roll steer.” This is the tendency of a suspension to — by virtue of its kinematics (i.e. its inherent geometric design) — turn when it compresses or rebounds, particularly in a turn. That’s right, even if you don’t change your steering angle, the vehicle’s front and rear wheels will literally turn as a function of the suspension “lean” in a corner.
This behavior allows Ford to dial in the vehicle’s handling, and to make sure the SUV tends towards a slight amount of understeer (less in this case than on a less sporty vehicle, a Ford engineer told me) at the limit. Here’s a quick definition of roll steer via the book How To Make Your Car Handle:
“[Roll steer] is steering of the rear wheels as as the car leans. Even cars with a solid rear axle can have roll steer, and many indeed have this characteristic built into the car. production car manufacturers use roll steer to give the car a high degree of understeer in a corner. Sometimes it is used to counteract the oversteering characteristics of a rear engine car.
When you lift a vehicle, especially if you make changes to major suspension components like control arms and axles, you’re likely to affect a vehicle’s roll steer characteristics, which Ford defines as angle of vehicle roll per degree of steering. The company has a goal for this figure (roughly five percent, though this figure might be degrees of steering per meter of suspension travel — I can’t remember), and meeting that goal while trying to jack up suspension height took real work. To understand this better, let’s look exactly at how roll steer works for both the front and rear suspension.
Front Suspension Roll Steer
Visualizing roll steer at the front suspension isn’t particularly difficult. You can see that the tie rod — which is tasked with pushing and pulling the steering arm that’s cast into the knuckle — swings in an arc as the suspension moves up and down, just as the upper and lower control arms swing in an arc. The relationship between the arcs that the tie rod and suspension arms (especially the lower, since the tie rod is closer to it) swing dictates the degree to which suspension movement tries to put that tie rod into compression or tension, changing the knuckle’s “toe” angle, and thus steering the vehicle.
Looking at the front suspension image above, which shows the driver’s side front suspension from the front, imagine the vehicle takes a right turn (the tire is turned a bit to the left in the image above; ignore that). Body roll would cause this outside suspension shown above to compress, so the control arms and tie rod end would swing upwards. The relationship between these arcs would cause the tie rod end to be forced outward relative to the knuckle’s steering axis, causing the vehicle to turn to the left during that right turn, creating an understeer behavior.
Rear Suspension Roll Steer
Solid rear axles also have roll steer built in, even though there’s no steering tie rod to change toe, and Ford had to make sure it could achieve its roll steer targets after lifting the Bronco up during the Raptorification process.
The rear axle steers during suspension travel via a change in “thrust angle” — in other words, the entire solid axle has a tendency to essentially “yaw” as one side moves up and down relative to the other. During a turn, the axle will tend to want to face inwards towards a turn, offering a stabilizing understeer effect. So while the outboard wheel (which has more vertical load on it, and thus has more responsibility to provide grip) at the front suspension tends to turn away from a turn during compression/roll, the outboard rear wheel is designed to turn in the same direction during compression/roll.
Suspensiondesigner.com, a website run by a suspension-design software company, breaks down roll steer (or “bump steer”) a bit, writing:
Positive bump steer gives a toe in tendency with suspension bump and negative bump steer gives a toe out tendency with suspension bump. As suspension systems are typically tuned to have a level of understeer, front axles typically have negative bump steer (toe out, understeer tendency on the front axle) and rear axles typically have positive bump steer (toe in, understeer tendency on the rear axle).
Like the front suspension, the rear suspension’s roll steer is a function of its kinematics, and can be visualized by looking at the arcs traveled by the control arms; there are four of those arms, pointed out above. These control arms run fore-aft parallel to the vehicle’s longitudinal axis. As they swing in their arcs, they push and pull the axle fore-aft. During suspension roll, the control arms on one side of the vehicle will be at a different point in their arc swings than the control arms on the other side, essentially pulling one side of the axle forward and pushing the other side back, changing the heading (thrust angle) of that rear axle.
If you look at the image above, you may be thinking: “If I turn to the Bronco Raptor to the right and load up this rear left suspension, then under compression, the left side of the axle will be pushed backwards, and the right will be pulled forwards, essentially “steering” the rear axle to the left, in the opposite direction of the turn.”
That’s actually not the case because the image above of the body-less chassis does not represent how the control arms sit at ride height. Here, as you can see in this image, at ride height, the control arms are essentially level:
This means that, as you compress that left rear suspension during a right turn, the control arms on that side of the axle would arc upwards, and actually pull the axle forward, steering the rear axle to the right, in the same direction is the turn, inducing the desired understeer.
It should be clear that the control arms are in their arc-sweep at the vehicle’s nominal ride height is critical (roll steer is clearly not linear) in setting its handling characteristics, which is why lifting the Raptor wasn’t as straightforward as one might think.
Why This Introduced Such A Challenge
Getting that lower control arm in the image above to sit relatively level to yield the right roll steer characteristics took some work. It required Ford to move the axle mount as high as possible, and the frame mount as low as possible. The problem with moving the lower control arm’s axle mount up is that there’s a hard limit: the centerline of the axle. Why? Because that lower control arm has to work in conjunction with the upper control arm to prevent “axle wrap,” the tendency of that rear stick axle to want to rotate about its axis under acceleration and braking.
As you can perhaps visualize, if that lower control arm’s axle mount were above the axle’s centerline, it would be unable to counter axle rotation. You’d essentially have two upper control arms, with an axle dangling off it below. This would be underivable.
This meant Ford had to lower the frame mount considerably, hence the big, blue lower control arm bracket shown below. It sits lower than the standard Bronco’s lower control arm mount, but I wouldn’t exactly call it rock bait; it’s still way up off the ground. (If you’re curious what that silver block is on the frame, I think it’s some kind of controller for the semi-active suspension).
Leveling out the upper control arm to help the vehicle get the desired five degrees of steering angle per meter of suspension travel (or however Ford measures it) was also nontrivial, since the frame crossmember mount wasn’t something Ford wanted to change, as it had been optimized for the fuel tank and exhaust package. As a result, the rear axle’s upper control arm mounts tower well above the axle tube:
As for the front suspension, the lower control arm hard points are the same as those of the standard Bronco. With the lift and the longer control arms, the taller suspension changed how the vehicle steers as a function of roll. As a Ford engineer told me, lifting the Bronco meant the vehicle is now “operating at a different region when we’re on-road.” In other words, the ride height is now at a different point in the control arms’/tie rods’ swinging arcs.
The change in ride height brought with it a new nominal location along the control arms’/tie rods’ arcs, and because — as previously mentioned — roll steer isn’t linear, the new “starting point” changed how additional suspension motion (during roll) affects steering. So, to hit their roll steer targets, Ford engineers adjusted the height of the knuckle’s steering arm to make sure that tie rod pushes and pulls in just the right way as the vehicle rolls.
Durability/Stiffness Challenges
As you may imagine, designing a vehicle to handle the absurd loads associated with sending a 5,700 pound vehicle on high-speed desert trails involves beefing up some parts. On the Bronco Raptor, that means newer, tougher coilover mounts on the frame at the front and rear, as well as auxiliary jounce bumpers [Editor’s note: “Jounce” sounds like a word David made up just now, but I know it isn’t. But it sounds like it. – JT] to help the ones built into the dampers when the suspension bottoms-out.
Because I’m a bit obsessed with packaging, I’ll note that those new jounce bumpers required re-shaping of the front sway bar ends:
The shock towers — based on the Ford F-150 Raptor’s (the damper architecture — i.e. the structure, but not the valving — between the two vehicles is also the same) — aren’t just “tougher,” they’re taller, and that means the suspension loads have a larger “lever” to try to twist the frame to which those towers are welded. To combat this, Ford added reinforcement to the frame. Chassis engineer Andy Lane referred to it as a “doubler plate that increases the torsional stiffness to allow for the shock tower loads.” Ford highlighted the stiffened part of the inner frame in blue in the cutaway part below:
Other reinforcements that Ford mentioned include a stronger steering rack housing to handle the incredible side-loads, especially while rock crawling; tie rods (which I showed earlier) that are apparently larger in diameter compared to those on the standard Bronco (they still look small to someone used to solid axles); and higher-strength front halfshafts (which I showed earlier, as well). I’m fairly sure Ford said the extension housing on the front differential is also new (that’s the aluminum thing bolted to the black cast iron differential), which makes sense given the wider track width:
That Dana 50 rear axle is unique to the Bronco Raptor; it is big and apparently quite strong:
Also blue (i.e. new) on Ford’s chassis model are the rear coilover mounts, which are a “dogbone” style, fastened via two bolts. Ford spent considerable effort trying to package the dampers in this area, as I showed earlier.
The rear hitch has also been reinforced via two ties/members that run through where the exhaust would have been on the standard Bronco; this apparently helps crank up the tow rating by 1,000 pounds to 4,500:
The exhaust, by the way, has been moved ahead of the rear axle, and though it’s unprotected, it is made of thick steel, and does include little guides to make sure rocks don’t get caught on its front lip:
It features active valves so the driver can chose her/his exhaust note:
That’s just looking at the chassis; what I found interesting is that the body itself had to be stiffened up, as well. With a body-on-frame vehicle, the frame takes up the vast majority of suspension loads, so the body – isolated from that frame via rubber mounts — really doesn’t have to be the most rigid thing. But it can’t be a limp noodle, because the body and frame are a system, and relative motion between a limp-noodle atop a frame that flexes as it travels over harsh terrain is going to not only cause significant issues with noise, vibration, and harshness for the passengers, but it could also negatively affect steering response (I assume this is because a moving body — to which the steering column is mounted — relative to a frame is probably not great for steering precision. Plus, lack of rigidity in the body is just another thing to “flex” before the vehicle actually takes the driver into a turn).
To stiffen the body, Ford added an extruded aluminum cross-brace to the B-pillar, and a carbon composite brace for the C-pillar crossmember and rear sport bar; chassis engineer Andy Lane says this cranked up torsional rigidity by 50 percent, and that this, along with re-tuned body mounts (stiffer up front to handle all the weight) yields a more comfortable cabin with better dynamic response.
What Was It Like On-Road?
Okay, so enough about the tech for now — let’s talk about how this thing drives.
Obviously, the first thing I noticed when driving the Bronco Raptor on-road is just how enormous it is. At one point, I pulled next to an older couple in an old Nissan sedan, and they literally looked at me and laughed. I knew why, they knew why — nobody had to say anything: This vehicle is just absurd.
Right off the bat, I hammered the throttle and listened to the roar of that 418 horsepower 3.0-liter EcoBoost V6. With those active exhaust valves, the motor sounds lovely, though it doesn’t quite have the presence of a V8 engine. It’s more of a nice, aggressive symphony, and not a million ton avalanche barreling towards you.
Acceleration was good, but I’m not going to pretend that 418 horsepower is a lot of grunt for a vehicle weighing over 5,700 pounds. That’s not even the same power-to-weight ratio as a Volkswagen Golf GTI, and nobody ever accuses the GTI of being that quick.
The power wasn’t immediate off the line; upon hammering the rightmost pedal, the nose lifted and the vehicle drove forward. A moment later, a wave of torque hit the rear wheels and shot the Braptor’s nose sky-high, as the rear squatted and the front suspension showed off its travel.
Once out of town, I hit some gorgeous canyon roads to see if the Bronco Raptor’s wide track width helped reduce load transfer to maximize grip, and if that optimized roll steer gave the vehicle the dynamic response Ford was going for.
The Raptor may have hit Ford’s dynamics goals, but it didn’t hit mine; I found the vehicle’s on-road handling marginal. A Ford rep, at a pitstop, asked me my thoughts; this is standard practice, but can make for some awkward conversation, as it did when I said “It’s definitely a purpose-built machine,” to which the rep responded: “Oh, you don’t like the handling? Everyone else likes it.”
I’m not a dynamics engineer, and I don’t race cars; I can’t really even talk authoritatively about things like steering feel and lift-off oversteer and other geeky car-review dynamics terms. If you want that kind of authority on this vehicle’s on-road handling, seek out Jason Cammisa’s review; he’s an excellent driver with a great handle on on-road dynamics. With that said, I know good handling when I feel it, and the Bronco Raptor’s ain’t it.
Turning the steering wheel rotates the front tires with immediacy thanks to the precise steering rack, but the off-road SUV doesn’t turn immediately, because there’s plenty of compliance everywhere. There are the huge sidewalls on those 37-inch tires, there’s the cushy suspension, there’s flex in the frame, there are the rubber body mounts between the frame and the body, there’s flex in the body itself — the transient response time between when I turned the wheel and the vehicle actually goes in that direction is noticeable, as I found it to be the case on the standard Bronco, as well.
In the turns, body roll, brake dive, and squatting were all noticeable, resulting in a vehicle that just didn’t feel at home on twisty roads. But that’s obvious. It’s a 5,700 pound off-roader with a high-travel suspension and 37-inch all-terrain tires. I’d be more surprised if it could handle like a sports car. (I want to be clear: It wasn’t horrible handling. It was totally manageable — it just wasn’t a precise-handling sports car on those canyon roads).
On the plus side, the ride is decent. I’m not sure it’s any better than the base Bronco, but it’s totally daily-drivable, even on highways, and even with the noticeable noise of air trying to get around those huge meats, exposed suspension bits, and squared-off cabin.
Off-Road
I say this all the time, but I’ll repeat it: The single most important attribute a vehicle needs in order to be an exemplary off-road performer is favorable geometry. And in that area, the Bronco is both incredible and awful, with the former dominating.
Geometry
The awful part has to do with the vehicle’s size, which is astronomical at 86 inches wide (the biggest Wrangler is about 79 inches wide) and 78 inches tall (about three inches taller than the biggest Wrangler); this could easily cause trouble on tight trails. I was driving in the desert, where trail width was often measured in miles, so this was no issue.
As for the “incredible” part of the Bronco’s geometry, well: Thanks to the tall suspension and huge tires, ground clearance is 13.1-inches, helping the Braptor achieve an approach angle of 47.2 degrees, a departure angle of 40.5 degrees, and a breakover angle of 30.8 degrees.
These figures are excellent; For comparison, Jeep’s Wrangler Rubicon Recon — the biggest, baddest Wrangler of them all — falls short in every area except approach angle, where it wins out by just a couple tenths. The Jeep’s smaller 35-inch tires are doing it no favors:
Traction, Gearing, Articulation, Pedal Calibration
The big BF Goodrich KO2 tires managed great traction on rock and sand, though they’re fairly useless if they’re not on the ground or if they’re not receiving power. Luckily, the Bronco has that on lock, literally; the front and rear locking differentials, activated by a satisfyingly squishy switch atop the center stack, are the best in the business in terms of actuation, feeling almost immediate.
With the lockers on, torque can be sent to any wheel with traction. How much torque, exactly? Well, with a 4.7-to-one first gear ratio, a 3.064:1 low range ratio, and 4.7:1 axle ratios, the Bronco has a crawl ratio of about 68 to one. That’s how much the engine’s torque, which peaks at 440 lb-ft at 2,750 RPM, can be multiplied by the time it reaches the wheels, and let me assure you, that’s plenty of grunt, even if the crawl ratio isn’t quite the Wrangler Rubicon’s. There is, quite literally, no hill too steep for the Bronco’s engine and gearing.
As for making sure tires stay on the ground, Ford says the front suspension offers 13 inches of travel while the rear can move 14 inches. While those numbers are great, they don’t tell the full tale, because the way the suspension flexes is as important as travel itself, and that’s pretty obvious when you look at the Bronco’s rear axle. That thing just flows into deep holes, preventing the rear tires from ever lifting off the ground.
The front tires, though, did lift every now and then. Would a solid front axle allow for better suspension flex? No question, but — as I’ll discuss soon — the tradeoff wouldn’t be worth it. Plus, the Bronco’s rear axle flexes so well that only the biggest boulders could get one of those front tires to lift.
Of course, it doesn’t matter how much traction or torque you have at your wheels if you can’t control it. That big crawl ratio helps give lots of torque at low vehicle speeds, and while that’s helpful when it comes to low-speed vehicle control, pedal calibration is key. I put this to the test on a gnarly, boulder-filled section of the King of the Hammers off-road race course; Ford had spotters every 30 feet, each holding a stick to precisely guide my steering wheel so I could navigate the terrain without body damage. I had no trouble climbing steep rocks at 1 MPH; the pedal calibration was great.
Ford offers a one-pedal driving option that would, at least theoretically, preclude me from having to use left-foot driving to keep vehicle speeds down, but I never got comfortable using that, and I even confused it once to where pressing the gas pedal all the way down elicited no response from the engine. I’m still not sure what happened there, but regardless, left foot braking works great, and crawling the Raptor up the perfect off-road line to prevent me from being yelled at by a spotter was no problem at all.
Honestly, the biggest issue I had with off-road vehicle speed control had to do with the one-two shift. Sometimes I’d be slowly crawling down a hill in low range, first gear, and then BAM the transmission would shift and I’d be careening down the obstacle far, far too fast. Even the two-one downshift was far more violent and unpredictable than I’d like. Luckily, there’s a manual mode that allowed me to lock the vehicle into gear.
Underbody Protection
The entire underside of the Bronco is well protected by thick metal skid plates — the transmission, transfer case, engine, steering, and fuel tank all have thick shields. There’s really not a whole lot for me to say, here, though I’d prefer if the rock sliders (to which the running boards — which I’d yank off — are mounted) were perfectly smooth on the bottom, as the brackets tying them into the body could get caught and prevent sliding:
The High-Speed Off-Road Hardware
As for high-speed off-road hardware, we’ve already discussed the high-travel suspension. A key component of that is the 3.1-inch diameter Fox semi-active internal bypass dampers, with a remote reservoir in the rear and an integrated reservoir up front. The “semi-active” part means there’s a computer that pays attention to the suspension’s motion via ride height sensors on the two rear lower control arms and on the front upper control arms. Have a look:
The sensors can tell the computer if, for example, all four wheels are at full droop, indicating that the Bronco Raptor is jumping. Called “Jump Mode,” Ford says the vehicle will adjust damping (stiffen it) with the understanding that the vehicle is about to land hard on the suspension.
So, DT, How Did You Like It Off-Road?
Ford started everyone out on a rocky trail in the California desert. There were some sections that benefited from a spotter, I did scratch a skid plate here and there, and I will say that I tried climbing up rocky and sandy grades with the differentials open and I did at one point start to get stuck (a quick tap of the rear locker, and the Bronco stomped its 37-inch tires to the top). So the trail wasn’t that easy, and I expected it to be the extent of the rock crawling that Ford would put the Bronco Raptor through; after all, in my head I had labeled the Bronco Raptor as a desert-runner, not a crawler.
But I misjudged how bold Ford’s PR team would be, and also just how capable this machine was on the rough stuff, because this little rocky trail was nothing compared to the section of the King of the Hammers course that I would next be trying to get the Bronco Raptor through. Just look at the photo below; that’s the image I had out of my windshield at the base of the “trail”— just a humongous boulder field with some umbrella-covered men holding sticks.
I’m very comfortable driving off-road, so I hopped into the first Bronco headed up. I have to admit that, seeing the view shown above, I was both excited and also incredibly surprised. “I cannot believe Ford is sending journalists up this!” I remember yelling. Usually off-road trails at press-launches are perfectly groomed, with inclines matching exactly the vehicle’s approach and departure angles. But this wasn’t that; parts of this trail would challenge even the Bronco’s excellent geometry, forcing the vehicle to rely on its skid plates.
Metal-on-rock mashing, bashing, and growling was in the air that day, but every Bronco that attempted the trail — with drivers having varying degrees of off-road skill — made it up. My run was incredibly smooth thanks to some great spotting, good pedal calibration that allowed for precise speed-control via left-foot braking, excellent power-assist from the precise steering rack, and a nice front-view camera with little guides to show what the tires would soon be crushing.
The excellent approach, departure, and breakover angles helped the Bronco get its all-terrains onto and over gargantuan boulders, while the skid plates below made sure that a misstep didn’t result in mechanical damage and that it could perhaps — with a bit of sliding — still get the vehicle up the trail.
As I mentioned earlier, the wheels usually remained on the ground, but the fronts occasionally lifted; the reality is that limits in the front suspension ball joints/CV joints make it such that the solid rear axle is just better able to keep its tires on terra firma. Nobody lifted a wheel on that rear axle that day, and given how treacherous that course was, that just tells you the absurdity of that axle’s travel.
Locking the front and rear axles, and engaging low-range made the Bronco neigh unstoppable [Editor’s Note: Horrible pun.]. There was occasional wheel slip over rocks, but it was slow and controlled. I have to say I wasn’t expecting the Bronco Raptor to be this good at rock crawling; it is genuinely excellent, though of course, its size puts it at a disadvantage.
Our trail wasn’t particularly narrow, but there were some large boulders that required very specific lines and I could see how a smaller vehicle might have been able to choose an easier path up. Still, the Bronco Raptor blew me away. It was poised, it was well-protected, it was absolutely epic. I, of course, still prefer a dual solid-axle setup in these conditions, but one of those can’t do what Ford had us do next: hit the desert at high speeds, comfortably.
We started on a dry lake bed; Ford had set a little rallycross course up on the flat, slippery surface, and I just slung the Bronco Raptor around slaloms, living the dream.
I have to admit that I don’t think I learned anything profound about the Bronco Raptor sliding it all over the place on that dry lake bed. The brakes work well, the traction control system kicks in if your driving sucks too much (and mine did), and the motor sounds like a lot of fun when you really rev it and load it up.
Where I did learn a lot about the Bronco Raptor was on a full facing circuit that Ford had either built or just pieced together out in the desert. It was filled with obstacles — big dips and bumps and washes — and at 60+ mph, the Bronco’s suspension danced.
Watch the video at the top of this article, and you’ll notice how heavily I have to rely on voiceover. This is because, while I was bombing down this desert racetrack, my brain could come up with nothing insightful to say other than “Woh ho ho! It’s soooooo good!” [Editor’s Note: I can hear David’s “woh ho ho” in my head vividly. I think it’s his specie’s mating call. – JT]
Truly enlightening stuff, I know.
But there’s a reason for this; it wasn’t just that I had to remain focused on the course ahead, it was that I was having some of the most fun I’ve ever had behind the wheel of a car, and I wasn’t about to let things like my “job” screw that up. I just let myself geek out, laugh, yell, and marvel at the way the Bronco Raptor’s suspension seemingly took a steamroller to the jagged earth below.
Hitting some of the holes and mounds that I drove over at 60 MPH would likely total the vast majority of cars out there. On numerous occasions, I realized I was coming in far too hot, and was about to hit a two-foot divot in the ground. I squinted and tightened my face muscles, gripping the wheel hard in anticipation of drama that never came. So I drove faster and faster, and the Bronco just continued to absorb any hazards in the dirt ahead, making me want to accelerate even more to the point where, eventually — thanks to this machine’s capability — I was driving beyond my own personal limits, and that was incredibly rewarding.
I also got to jump the Braptor; that was fun. (Ford actually had one of its electrical engineers jumping the Bronco Raptor; oh what a life he’s living after studying things like Coulomb’s Law and concepts like back EMF and Laplace Transforms).
Conclusion
The Ford Bronco Raptor is a genuine marvel of off-road engineering, and unquestionably the most all-around off-road-capable new vehicle in the world. I’m not going to call it the most capable vehicle ever built (I think its size holds it back), but its well-roundedness makes it an instant off-road legend. To be able to dominate both boulderfields and desert race-courses to this degree is just not something I’ve ever seen in any off-roader before. The engineering effort that Ford put into getting the vehicle to this level — overcoming dynamic challenges of a taller vehicle, figuring out packaging solutions for a suspension system that flexes that much, strategically toughening up components to handle the high loads — something worth celebrating.
Of course, 15 MPG and $70,000 aren’t optimal, nor is on-road handling, but these are compromises. And as an engineer, I’d be a fool to dwell on things that were clearly necessary to make this Bronco fulfill its intended function so perfectly. The Ford Bronco Raptor is a purpose-built off-road beast.
Without doubt, the best coverage I’ve seen. I’m not interested in the regular Bronco, but this peaks my interest. Probably way too big though. I’d like to see a video of one on Moab Rim. It’s too bad no one in Moab rents any sort of Raptor. It’d be interesting to compare a Jeep and a Raptor back to back on a road like Gemini Bridges. I feel like I always have to go slower on that road than I’d like because the ride gets too jarring at higher speeds.
Thanks for the deep dive, DT!
Good to have covered the roll-steer aspect. F’d-up roll steer is what makes most lifted Jeeps so awful on the highway, and Ford apparently didn’t want none o’ that.
I kind of wanted a Bronco, but with what I’ve put in to my FJ (money, but also hours and hours of wrenching) it didn’t quite tip the scales. This tips the scales handily, though 70K would be tough to swallow.
It seems like there are a lot of love letters to fossil fuels being composed in the form of really excellent cars these days. It won’t be long before vehicles like this are a thing of the past.
It’s funny how Jalopnik’s review was on the verge of calling it a sports car in terms of on-road handling.
Wow this article is so long I didn’t know David Tracy knew this many words.
What I take from this is really how hard Ford worked to make a vehicle noone will want.
Now I get this thing has all kinds of crap in it to make the average daily commute better. I also get that it might be better than a human driver, maybe because computers fail a lot. But why would anyone buy it? If I am into 4 wheeling I want to manhandle this beast over rough terrain to prove my mettle. I have no interest hiring an expert to drive a vehicle over wild terrain while I sit in the passenger seat. What do I tell other 4 Wheelers? My vehicle is so good I hired an expert to drive it in bad terrain and he did good? This isn’t horse racing where you hire a jockey. Also if the vehicle capability is so good anyone can take on the roughest trail What next Elons 2nd level autopilot programmed for trails and the we just sit in the passenger seat. What next Disney World rides based on trails around the world? Hey with enough money I can take a helicopter to both the north and south pole in 24 hours. Should that surpass Admiral Byrd doing it in wind powered boats and dog sleds? Hey get a helicopter to take you up to the top of Everest. Beat everyone’s time. Ooh I have the record. Jeep realizes their customers want to be part of it. No manual Bronco means Ford doesn’t get it. I’m surprised DT doesn’t because he is more about the journey than anyone I know.
No one will want?! First year sold out, adm’s O plenty, demand is certainly there Regardless…These arnt intended to be mass produced. Let’s just concede that these things are awesome. These journalists and professional drivers seem to think so.
Super interesting from an engineering standpoint. Given the overlap with the F-150 raptor, the purpose-built nature of this makes it much cooler to me than the truck which seems like it starts from a compromised position. I’m prepared to admit I could be wrong about that, but I’m not in the market for either so I’m sure Ford cares less than nothing what I think.
It’s still going to make me angry to see these parked, freshly detailed, outside whole foods, as these are actively antisocial if used only as a lifestyle accessory, but so are any number of other things. At least they aren’t fun on the road?
I love the level of detail you show David
What about the tail lights? -Torchinsky
New Bronco. What a joke to the humble purist.
Thanks for the laugh Ford.
I already don’t care.
I had crawler’s with tires that big before anyone paid attention to tire size.
I have boulder scars on my rib cage from tipping a Jeep when I was nine years old.
I’ve got half blind welders eyes starring back at you.
Get off my trail you wealthy untrained “enthusiasts”.
Get your $90,000 behemoth out of my way.
This isn’t for you.
I’ve had cheese farts that will stink longer than this $70,000+ Bronco love will last.
It’s a stupid vehicle for stupid people with more dollars than brain cells.
Give me a classic “lunchbox” in the same price range and I’ll be much happier.
Spoken like a small jealous man. You know better than the author huh? And the numerous professional drivers/journalists that ACTUALLY DROVE them?! Lol. Stupid ppl huh? Last I checked, by in large, it takes SMARTS to have “dollars”. Never understood clowns like you, EVEN IF I didn’t like a vehicle, I don’t trash ppl that do. Especially something that is as mechanically awesome as this is. Must suck to have so such hate inside. Can only imagine the temper tantrums you will have when u actually see them on the road.
If u “don’t care” keep it moving. Many ppl do, including the author of this article. Let ppl do what makes them happy, u sound like an elitist. As long as they are being safe and have the proper decorum on the trails….have at it. It’s not “your trails”.