Rear upper control arm bushing

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Registered User
My 90 5speed SC needs upper control arm bushings it's the inside as in toward the center of the car near the spare tire well. So my question is, are there 2 bushings per side or just one large bushing? I though it was a bad wheel bearing so I started to pull the rear hub assm. To change that and noticed the excess play was in that control arm that comes off the top of the hub assembly to the center of the car.
 
That's a great read unfortunately doesn't help my particular situation as the rear control arm bushings he not ates very well are the wrong end I belive the IRS cradle is the outer portion of the upper control arm and I need the inner upper control arm but still a very well put together post.
 
Just 1. It needs to be pressed out/in. It can be done with a screw and some washers, if you're creative enough. Otherwise, take it to a shop. The center bushing MUST have an inner sleeve that rotates off center.. that is what adjusts your camber. If the bushing does not have an innner sleeve, it is wrong!
 
Thanks for all the help I managed to get the worst side done I'll tackle the other side next week or the week after but because of yall I knew what part to get and what not to get I love this forum so many willing to help sadly I don't get to help others as I'm learning about these cars but one day maybe..... Ha
 
Drove it for the first time since replacing the rear drivers side upper control arm bushing on the interstate and getting alot of vibrations out the rear of the car at 65moh and worse as you go higher in speed it always shook a little bit but certainly alot worse now I know the passenger side rear upper control arm bushing also has a little bit of play but it's been that way since I got the car I've got the bushing just haven't had the time to install it any suggestions what it could be... Definitely coming from the rear jacked up and secured the rear end and started the car and got it up to 55 on jack stands and thr vibration is definitely there...
 
You started out chasing a vibration at that corner of the car, as I understand it.

You decided is wasn't the wheel bearing, then went after the upper bushing, now it's worse - does that sum it up?

I normally wouldn't expect an average worn bushing to cause a noticeable vibration on it's own, in this example, and my first suspect would be the wheel bearing, but let's list possible suspects:

Primary:
- wheel bearing
- wheel/tire balance
- cracked wheel
- tire
- 1/2 shaft - joints worn; bent

Secondary:
- Driveline
- stuck caliper/warped rotor
- ...

When drive the car, do you feel the vibration in the seat of your pants, or in the steering wheel or shifter? Mirror shakes?

Does the vibration change when the car changes direction of travel at speed?

When you test on jack stands, what is the angle of the wheel? As driven, dropped, ?

Have you had the tire/wheel balance checked? Wheel been inspected? Moved another tire/wheel to that location? What amount of tire wear is there?

Did you remove and/or disassemble the axle shaft?

How many miles on the car/wheel bearings?

How did you determine the wheel bearing was still servicable?

How much weight does the car usually carry beside driver and fuel?

Any other work done on the car recently?

Did you have the car 4-wheel aligned after doing the bushing?
 
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So on the stands yes the wheels are lower than when driving the vibration whether or not on stands starts at about 50-55 no viable damage to axels or boots I didn't have it aligned due to the fact I still have to do the passenger side bushing the way I determined the bushing are bad was I knew the rear tires had some wobble as in if you jack it up and physically grab the tire you could move them and hear a slight clunk sound which lead me to the wheel bearing theory but as I started to change the wheel bearing I noticed that the upper control arm was moving so I changed the drivers side and that stopped all the wobble and slight clunk I was having I noticed that if you accelerating the sound is lessened as well as the vibration you don't have to accelerate very much at all as long as your slightly accelerating it lessens quite a bit but when you release throttle you get an auditable sound and vibration follows the sound rear view shakes with sound and vibration I did remove the axel nut on drivers side when I was about to do the bearing also had the shaft out of the hub but was careful to realign shaft splines and retighten axel nut..
 
And going to have tires and wheels balance checked when I do the other upper control arm bushing no viable damage to wheel and certainly since I've had the car I have hit any pot holes or curbs or anything
 
Tires are in good shape I'd say 85% tread but they are cheap quality tires that where on the car when I got it Falken tires but no uneven tread wear or lumps/flat spots
 
Got it, thanks.

I'd do low hanging fruit...wheel balance - might mention you're chasing a vibration and ask them to look close.

You could get the rear off the floor, with the wheels at same angle as when loaded, then with the trans in gear/park and the brakes released, grab each axle shaft and spin by hand while eyeballing, then set the brakes and check freeplay on each 1/2 shaft, rotating by hand.

Still no joy, since the miles are high/unknown on the running gear, I'd plan on at least one wheel bearing.

Alignment to wrap things up.

Good luck.
 
Alright well that was a scare and got scarier when I found the problem one had absolutely nothing to do with the other but some how my drive shaft bolts had loosened to the point of almost falling out I could turn them with my fingers can't belive the whole drives haft didn't fall off/disconnect but either way all the bolts are there little bit of thread locker and good tighting and back to normal
Once again I appreciate the help
 
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