Thread: Possible Bent Chassis or Rear Axle Housing

Originally Posted by discorevy

Just going off the last attachment, the 10 mm out combined with the 3 mm toe in on the rear left would make me think the housing is on the wrong thrust angle rather than bent , if all else is true , you could always try swapping radius arms, but if its driving OK , not veering and pulling up straight when hard on the brakes and not wearing tyres unevenly, it's probably acceptable

I think you are correct, i just figured the 3mm toe in was the same on both sides but as you quite rightly point out it is only written in the rear left box. The axle is behaving as if the rear drivers side radius arm is shorter (or the passenger side longer). I always apply a little right down to keep it straight, i thought it was due to road camber and it still might be. I think it is wearing the front a little uneven (the tires are at the end of there life), inside on one and the outside on another. It isn't unstable to drive at all. I just want it sorted because i'm too pedantic.

I'm confused.

Last image shows left track 2535, right track 2537, does it not?

So 2mm out, not 10mm?

And vehicle has suspension lift so track will be shorter than 2540mm from factory, no?

Originally Posted by ballbag

I'm confused.

Last image shows left track 2535, right track 2537, does it not?

So 2mm out, not 10mm?

And vehicle has suspension lift so track will be shorter than 2540mm from factory, no?

10mm is the factor of 2mm out over a distance of 2537mm. It is 2mm out at the rear and the 10mm was measured at the front.

Over exadurated the wheels look like this:
|--| Front
/--/ Rear

The wheel base will be fractionally shorter due to the lift yes, either by 3mm or 5mm it would seem.

Sorry re-read my post and realised I'd said 'track' instead of wheelbase. Then looked at the 'track' diagram and now understand. Sorry about that.

Last dumb question for the day.....

If the thrust angle was wrong, wouldn't right rear show 3mm toe out? Any metal filings in your rear diff oil?

Another thing that I'm not quite grasping is if the axles, bushes and arms are straight how right wheelbase is longer with less castor angle.

This seems to be at least an 8 beer problem.....unsolvable on a Wedneday night.

Can we assume that you changed all the bolts for the bushes with new ones too?
Or did you just change the bushes?

So going by the track measurements, you are looking for something that is about 2mm out of whack. Not an easy task.

As you have already stated, radius mounts at the axle end is the next thing to check. Failing that, go back over the mounts at chassis end and the rods themselves with something more accurate perhaps? How did you measure these?

I've been busy in meetings today and have been unable to do much with this. However to answer some questions.

No I did not change the bolts, on the bushes.

The thrust angle is out, but the reason it does not appear to be equal on the opposite wheel is I think there is already toe in manufactured into the axle housing. I'm not sure what is is but i'm guessing about 2mm. So when it pivots on one wheel the toe in on one decreases and the other increases. It does necessarily mean on of them is toeing out yet, just toeing in less. Does that make sense? This is just a guess.

I measured the radius arms from centre to centre on the mount bolt holes, the chassis end to the first axle bolt hole. It was only by tape measure and while fitted to the car. Hence why I need to check them again more accurately before changing the mounts.

If the radius arms are equal, I'm going to adjust the mount on the axle housing by 2mm on the rear passenger side to see if I can correct the issue. It will either work or it wont. If all else fails i'll fit a new axle housing and hope for the best.