Bronco Raptor Rear Axle

[trussdevils]

I have a 2023 Braptor and I have a warped feeling coming from the driver side rear wheel. It has affected the way it drives...warp feeling from the left rear, vibration in the lower left side of steering wheel, the rear end is much more stiff and rigid than it was before. I have had my wheels and tires inspected multiple times and there is no issue with them, I even switched out the wheels/tires with another set and it made zero difference. I think that the issue may be a damaged wheel hub or damaged rear axle. I have taken my bronco to a couple of dealerships to be inspected and both claim that everything looks and is testing ok. However, I know that it isn't. I need to find an independent mechanic to thoroughly inspect and test it. Any thoughts or recommendations?

 

[Johnny Raptor]

What wheel/tire combo are you running? Were you able to put the stock wheels/tires back on for comparison?

 

[trussdevils]

I have 37" ridge grapplers. I still have my OEM wheels and tires and put them back and it does the same exact thing. Both sets of times are balances and have been tested and there are ZERO issues with the wheels/tires. I must be coming from the axle or the suspension.

 

[Johnny Raptor]

If putting the OEM wheel setup back on there doesn't change anything, I tend to agree with you unless the air pressure is WAY high.

If you change to Baja mode on your suspension settings, can you feel any difference? Seems like I remember reading that the Fox live valve shocks on the F150 Raptors would default to full stiffness if the shock solenoid lost signal, so maybe it's something like that. Full disclosure, I have no idea if the Bronco Raptor live valves have the same behavior, so I could be completely off-base on that. It'd be easy enough to check the wiring harness on the shock to see if there's any obvious damage that might have occurred when changing the wheels, though.

If it were mine, I'd check the fuses and wiring first, then try to find a way to compress the rear shocks as much as possible (traverse a ditch, find somebody with a CTI Ramp, LAUNCH IT, etc...) and see if that changes the feeling at all.

Also, I know this might be a stupid question so I don't mean to insult you at all, but the vibration you're feeling in the steering wheel isn't the Lane Keeping Assist, is it? Just gotta cover all the simple possibilities first

 

[trussdevils]

Thank you for your comments. I appreciate it. Supposedly the dealer did a hard rest on the IWE the first time I took it in and they replaced what they said was a leaking CV axle (front left). They said no signs of a bent axle or hub. When I put it into Baja mode then back to Normal the front and rear axles feel sloppy. The suspension also does not feel much different when I switch between the three suspension levels (normal, sport, baja). The shocks do feel stiff, no where near as smooth as it did up until the issue first started. I think it either a bad axle (or axles), bad drivetrain..and/or something with the suspension and the drive modes. When I drive I feel a fairly constant warped feeling from the left side (like a bent wheel or axle, but all wheels have been tested and are fine), mild vibration from left side of steering wheel as well. BTW - I know its not the lane assist because I turned it off....

 

[Johnny Raptor]

Yeah, I just had to mention the Lane Keeper because it lightly vibrates the steering wheel. I leave it turned off on our Broncos; it’s annoying to me.

A couple of other questions:

Does the vibration change with speed or is it constant? Since the dealer worked on the IWE, is it possible it’s in 4WD all the time? It’d definitely feel weird on pavement if it is. I know on my Gen 1 Raptor the IWE’s are vacuum activated, so if they lose vacuum they engage 4WD. I don’t know if this is true on my Bronco Raptor, though. Somebody else may be able to weigh in on that.

Do you know if they replaced a damaged CV Boot or the whole CV half-shaft? If you had a torn boot and lost the lubricant or if dirt/water got into the CV joint, it could’ve trashed it. A bad CV joint could also cause a vibration.

Not sure if any of that helps you out, but those are the things that come to mind based on the symptoms you mentioned. I’m also assuming you aren’t running high pressure in your tires (like 45-50 psi) and that the alignment is in-spec and no other mods have been made to your truck.

 

[guncarsguitars]

just left side of wheel vibrating..... well it's not steering or bent front sus. components*(the whole wheel would shake). if it is an axle issue the vibration and "warped" feel will fluctuate directly tied to vehicle speed. As you go from stop to 65, you would feel changing vibrations or feel and it will be the exact same every time you accelerate. Axles can bend but unless you've been quite air-born or slamming through crazy terrain I doubt it..... and it's easy to diagnose.
(Bent wheel and bad tires are also very easily diagnosed)
The shocks or hubs seem more likely. That just the left side pf the wheel has me thinking the nanny system may be acting odd. Have you turned off all driver assist features?

Lastly, see if you can find another Braptor owner near by. Get together and drive each others Broncos.
Compare notes. If there is a noticeable difference, get driving opinion notes from the other guy. Go back to dealer with this info.