Spied: 2021 Bronco 4-Door Shows Off Its Roofline As It Drops Heavy Camo

[BAUS67]

I questioned this a few months ago when the first pics came out. I Agree, it should be mounted just on the inside of the frame, regardless it will reduce ground clearance as you get back, but it would be less reduction, and if you made them beefed up, it would provide a smooth rock slider type transition.

think:

.______
. \
. \

vs

.______
. |
. \
\

but alot shallower.

well, crap, my ability to make that work, didn't work.

Been there tried that. I found it easier to draw an actual picture and then take a pic with the phone, send to my email, download to computer, then post. PITA but I'm not tech savvy and it's the only way I could think how to do it.

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[BAUS67]

My buddy who builds rock crawlers said that the Bronco’s control arm setup is actually pretty sweet. He said it’s a combination almost of a JL and a 4Runner. As far as ground clearance... yeah we’ll have to see. But he said it was a good design for ride quality and articulation.

OK I'm not an engineer so I was just curious because most rock stars have them inboard mounted as JD said to use as a rock slider to get to control arm then slide till ya hit the tires with out a big "bump" in the road. A guy who builds I would believe.

 

[JimmyDean]

OK I'm not an engineer so I was just curious because most rock stars have them inboard mounted as JD said to use as a rock slider to get to control arm then slide till ya hit the tires with out a big "bump" in the road. I guy who builds I would believe.

I am an engineer. And I would be mounting them more forward and higher (so you don't f with the angles, which affects power steer, dip, etc) I know why they put them there. the engineering numbers say that was the best spot, length vs angle vs height. But there are 'poor' engineering decisions you make on off road rigs to gain some use-ability. This is one of those.

 

[Nickp]

OK I'm not an engineer so I was just curious because most rock stars have them inboard mounted as JD said to use as a rock slider to get to control arm then slide till ya hit the tires with out a big "bump" in the road. I guy who builds I would believe.

Here was his text, I talked to him a bit more in person which is where I got the further details

And for reference here’s him wheeling his rig, along with the top pic being some rigs he’s either helped build or done all the work on

If you wanna see more of his work here’s a shameless plug. He is not a Ford fan by any means so the fact he had anything positive to say about the bronco rear end is pretty funny lol. He’s gonna be the first guy I take my bronco to for sure!

https://www.nolimitsoffroadphxaz.com/gallery

 

[BAUS67]

I am an engineer. And I would be mounting them more forward and higher (so you don't f with the angles, which affects power steer, dip, etc) I know why they put them there. the engineering numbers say that was the best spot, length vs angle vs height. But there are 'poor' engineering decisions you make on off road rigs to gain some use-ability. This is one of those.

The last two sentences say it best. That's why you wouldn't see a "long arm" suspension from the factory because you end up with flex steer ( I think it's called ). Bean counters will say no way because someone will have an accident and then sue. That's how we ended up with TPMS sensors in all of our tires. When a long arm flexs it will steer the car one way or the other. Plus with what nickP just posted he says it there as well "lower arms are nice and flat". won't get that with mounting them inboard.

edit: so yeah the arms will have to be mounted lower because of keeping the length in check along with the angle.

 

[BAUS67]

Here was his text, I talked to him a bit more in person which is where I got the further details

And for reference here’s him wheeling his rig, along with the top pic being some rigs he’s either helped build or done all the work on

If you wanna see more of his work here’s a shameless plug. He is not a Ford fan by any means so the fact he had anything positive to say about the bronco rear end is pretty funny lol. He’s gonna be the first guy I take my bronco to for sure!

https://www.nolimitsoffroadphxaz.com/gallery

Nice rigs !!! and yeah the track bars and control arms should be as flat as possible but when making an off road rig sometimes things that should not be work the best.

edit: your rock crawling buddy would know about the flex steer thing I was stating above. it's common in a long arm. As it flexes to one side it will "steer" the rear in that direction.

 

[Jake_zx2]

Man, I just can't get with those damn bushwhacker flares :sigh:

 

[Fordboi]

I questioned this a few months ago when the first pics came out. I Agree, it should be mounted just on the inside of the frame, regardless it will reduce ground clearance as you get back, but it would be less reduction, and if you made them beefed up, it would provide a smooth rock slider type transition.

think:

.______
.\
.\
vs

.______
.|
.\
\

but alot shallower.

well, crap, my ability to make that work, didn't work.

you sure know how to confuse a guy lol

 

[SpursFan]

That WOULD be interesting... too bad solid axles are super complicated and it could never happen

False ?

 

[JimmyDean]

The last two sentences say it best. That's why you wouldn't see a "long arm" suspension from the factory because you end up with flex steer ( I think it's called ). Bean counters will say no way because someone will have an accident and then sue. That's how we ended up with TPMS sensors in all of our tires. When a long arm flexs it will steer the car one way or the other. Plus with what nickP just posted he says it there as well "lower arms are nice and flat". won't get that with mounting them inboard.

edit: so yeah the arms will have to be mounted lower because of keeping the length in check along with the angle.

ehhhh......

if your arms are flexing enough to make that kind of difference, they are WAY under engineered (undersized).

the issue that comes with the car steering itself when you hammer down is power steer. it is due to the torque on the pinion gear, which rotates in one direction, causing the passenger rear to sink, and the driver rear to raise, causing the car to tilt and auto steer to the right.
Unless you have enough power, then it actually steers to the left because you lose traction on the driver side with weight off the tire, and keep traction on the passenger side with weight added.
If you have even more power, then you break traction with both, causing the back end to typically drift to the passenger side. (ever notice how when you do a burn out you are normally countersteering to the right? that's because you car is trying to face left with the back drifting right)

But, to the original point. if components are actually flexing to cause steering issues, then someone done fucked up.

 

[BAUS67]

I was checking out long arm suspensions for my TJ upgrade until I caught wind of this Bronco stuff. Take this for what it's worth but I watched this a while back. I'm not saying the guy is right but he shows what I am talking about @ 10 maybe 11 minutes.

 

[BAUS67]

ehhhh......

if your arms are flexing enough to make that kind of difference, they are WAY under engineered (undersized).

the issue that comes with the car steering itself when you hammer down is power steer. it is due to the torque on the pinion gear, which rotates in one direction, causing the passenger rear to sink, and the driver rear to raise, causing the car to tilt and auto steer to the right.
Unless you have enough power, then it actually steers to the left because you lose traction on the driver side with weight off the tire, and keep traction on the passenger side with weight added.
If you have even more power, then you break traction with both, causing the back end to typically drift to the passenger side. (ever notice how when you do a burn out you are normally countersteering to the right? that's because you car is trying to face left with the back drifting right)

But, to the original point. if components are actually flexing to cause steering issues, then someone done fucked up.

Yeah I know what you mean there I'm a drag racer I know all about how a suspension reacts under GOBS of torque. …….. or maybe how a locker reacts when you "snap" off the throttle on a gravel road.

 

[JimmyDean]

I was checking out long arm suspensions for my TJ upgrade until I caught wind of this Bronco stuff. Take this for what it's worth but I watched this a while back. I'm not saying the guy is right but he shows what I am talking about @ 10 maybe 11 minutes.

that is extremely different than what you mentioned btw. What he is calling flex steer is heimjoint rotation play and 3 dimensional movement of the 4 triangles involved in a triangulated 4-link. which, as he points out, occurs when you do no properly design, or fully engineer, your 4-link. It occurs when the angles of the upper in and lower out do not match. Which granted is often the case, because you want your uppers as close to center as possible, and you can't bring your lowers in that much without interfering with your driveshaft.

HOWEVER. for all the different 'steer' issues he is talking about, how often do you see more than a couple of inches cycling on the road? The answer should be (almost) never. and these issues occur at more extreme travels. So, a 4-linked front and rear jeep (or bronco) should NEVER be seeing extreme travel angles at speed, only at low crawl rates, and frankly, these steering angle issues are not an issue at low speed, you aren't going to careen off a highway at 70 when you are doing 2mph in rocks.

the only time these are issues are high speed off road, namely, baja style vehicles. and baja style vehicles, last I checked, run 3 linked rears, and parallel 4 linked fronts with a panhard. those that do run triangulated 4 link fronts are going to be setup to keep the pinion angle constant, and therefore the steering angle constant because they are traveling at speed. High torque low speed crawlers are going to, or should be, setting up to minimize the delta in pinion angle from high to low travel.

gonna edit, the 4-link of the screenshot of that video, of that rear axle. is amazingly horrible. there is almost no angle on the lower links. that sob is going to slide side to side non stop. the lowest ratio of the angle on the lower links should be half the angle of the top, looks like he has a quarter or less. it is not very much better than a parallel 4 link without a panhard. it'll be find in the rocks, and nearly uncontrollable on the road.

 

[BAUS67]

that is extremely different than what you mentioned btw. What he is calling flex steer is heimjoint rotation play and 3 dimensional movement of the 4 triangles involved in a triangulated 4-link. which, as he points out, occurs when you do no properly design, or fully engineer, your 4-link. It occurs when the angles of the upper in and lower out do not match. Which granted is often the case, because you want your uppers as close to center as possible, and you can't bring your lowers in that much without interfering with your driveshaft.

HOWEVER. for all the different 'steer' issues he is talking about, how often do you see more than a couple of inches cycling on the road? The answer should be (almost) never. and these issues occur at more extreme travels. So, a 4-linked front and rear jeep (or bronco) should NEVER be seeing extreme travel angles at speed, only at low crawl rates, and frankly, these steering angle issues are not an issue at low speed, you aren't going to careen off a highway at 70 when you are doing 2mph in rocks.

the only time these are issues are high speed off road, namely, baja style vehicles. and baja style vehicles, last I checked, run 3 linked rears, and parallel 4 linked fronts with a panhard. those that do run triangulated 4 link fronts are going to be setup to keep the pinion angle constant, and therefore the steering angle constant because they are traveling at speed. High torque low speed crawlers are going to, or should be, setting up to minimize the delta in pinion angle from high to low travel.

Ok I thought I said flex steer and that is what he called it soo that's where I was going with that...... Thanks for clarifying all that and yes I realized most of the time you would not see it but ……. we all know how people are, look at the Raptor I can think back when it first arrived utube was full of people who thought they we invincible because of what the truck was. It might make a good chase truck but it's no trophy truck but people still think it is.

 

[Walnut]

Man, I just can't get with those damn bushwhacker flares :sigh:

I used the quiet time during quarantine to come to terms with those hideous flares. I'm at peace - but I tell ya, the rest of the exterior better be on point

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