Rear Upper Control Arm Problem

[Wonga Spar]

As usual, I'll preface by saying I don't exactly know what question I'm trying to ask- but here goes.

 

Took Supra for alignment, they finished, drove home and car pulled from side to side at high speeds (before alignment it was driving beautifully but wearing the inside of the tyres slightly faster than outside).

 

Took it back to them, they pointed to the silicon (seal?) above the bushing on the rear upper arm (pictured). They were able to play with the silicon and literally make it crumble, citing this as the reason the alignment was "correct" yet the car drove like shit.

 

They said I needed a new rear upper arm.

 

Bought (used) rear upper arm, with the exact same crumbling silicon situation. Can't find any reference to this silicon, or what exactly I'd need to replace in order to fix. Some people say just get new bushings? As is often the case when I try to fix problems, I buy 6 of the wrong things and ask for the wrong thing from the mechanic, they do the work, and nothing gets fixed- really trying to avoid this happening again!

 

Removed all the silicon (pictured) and the rubber bushing looks fine?

 

Would somebody kindly tell me what this is, what's gone wrong and what I need to ask for in order to get it fixed?

 

Thanks!!

Edited August 21, 2018 by Wonga Spar (see edit history)

[Al Massey]

That silicone is just to keep the crap out.

How much movement is there with the ball joint?

[Scooter]

Without any 'knocking' I would suspect play is more likely from the two bushes at the fixing points than the ball joints (ball joint should be fairly stiff, ie certainly shouldn't move if you tip the arm for example). The bushes have natural play/flexibility so it's hard to know how much worse it is than a brand new arm....

 

The rear adjuster bolts can seize or the bushes sleeve can be seized to the bush and adjusting can tear them I think.....will try and find a thread.

[Wonga Spar]

That silicone is just to keep the crap out.

How much movement is there with the ball joint?

 

If the silicon is just there to keep the crap out, the mechanic (once again) was just making it up as he went along?

 

On the new wishbone there's a TON of play on the ball joint, not sure about the set on the car.

[evinX]

If the silicon is just there to keep the crap out, the mechanic (once again) was just making it up as he went along?

 

On the new wishbone there's a TON of play on the ball joint, not sure about the set on the car.

 

Find a wheel alignment company with the hunter machine. Sounds like hes breathing bs.

[clay]

Im shore all the ajustment on the rear end is done on the bottom arms. what you are showing is the ball joint. if that is nakered get a new arm. but as other people have said. i think he is talking bull sh! t. take it somwear ells.

[Mike2JZ]

I used to have a similar side to side feeling on mine. The balljoint was still in good service, but the two rubber wishbone bushes were gone. Once I replaced them with polybushes I haven't had another issue since.

[rider]

Arm bushing or joints don't go from being fine to causing instability by simply loosening and then tightening some cam adjusters to set the alignment. As other have typed, the silicone can be easily reapplied, it has nothing to do with the operation of the ball joint.

 

I'd check they actually tightened the cam bolts back up to the specified torque and also that they haven't just stripped the bolt thread by tightening down on the cam bolt rather than the nut which would then allow the cam to rotate on and along the sub frame slot that the bolt feeds through and with that moving the toe setting on the wheel onto wobble setting. You'd need to take it to another alignment shop to get that checked, I'd recommend having a spare cam bolt and nut set in case one on there has been thread stripped.

[Chris Wilson]

The top arms have Rose the joints in them, not rubber bushes, the rear suspension is a big compromise as the top and bottom wishbones are too close together in an ideal world, but Toyota had to offset ideal suspension kinematics against a usable rear load space. Being so close together any wear at all in the arm bushings is magnified in serious toe change under acceleration and decelleration. I suggest the issues are down to to arm wear, lower arm bush wear, or set up, as in not being taken from the physical centre line of the front and rear subframes. Sometimes the old fashioned find the C/L by physical measurement and stringing the car up from that is the best Some of the none genuine arms are total junk. Poly bushes in ill considered places put massive mechanical stresses on arms and subframes.