Rear Suspension

[gaerisch]

Hello, I have a 2003 GT Coupe. I noticed not long after I put Eibach sway bars and Bilstien shocks all around(including quad shocks) the suspension in the rear started skweaking like the car was 60 years old. It seems to only make the noise on roads that are bumpy. Not pot holes but bumpy enough to make the rear go up and down considerably. I also noticed a sharp bang from the rear on hard bumps in the road. I’m thinking the rear control arms bushings are failing due to the new shocks and sway bars putting more pressure on them. Any suggestions?

 

[wmburns]

started skweaking like the car was 60 years old.

Did you use the molly lube that normally comes with suspension upgrades?

I also noticed a sharp bang from the rear on hard bumps in the road. I’m thinking the rear control arms bushings are failing due to the new shocks and sway bars putting more pressure on them

My vote is the sharp bang is the suspension bottoming out on the bump stop (or the bump stop is missing/broken).

Let me ask. When the new components were installed was the full weight of the car resting on the suspension when the nuts were fully tightened? If not, the control arm may not be in their "neutral" position and the result is something called "suspension wind-up".

Try putting the solid axle on axle stands so that the full weight of the car is resting on the suspension. Loosen and then re-tighten the control arm bushing bolts.

 

[gaerisch]

Did you use the molly lube that normally comes with suspension upgrades?
I did use moly lube for the front sway bar. The rear control arms are original and were not changed. Only the sway bars and shocks.
My vote is the sharp bang is the suspension bottoming out on the bump stop.

Let me ask. When the new components were installed was the full weight of the car resting on the suspension when the nuts were fully tightened? If not, the control arm may not be in their "neutral" position and the result is something called "suspension wind-up".

Try putting the solid axle on axle stands so that the full weight of the car is resting on the suspension. Loosen and then re-tighten the control arm bushing bolts.

Did you use the molly lube that normally comes with suspension upgrades?

My vote is the sharp bang is the suspension bottoming out on the bump stop.

Let me ask. When the new components were installed was the full weight of the car resting on the suspension when the nuts were fully tightened? If not, the control arm may not be in their "neutral" position and the result is something called "suspension wind-up".

Try putting the solid axle on axle stands so that the full weight of the car is resting on the suspension. Loosen and then re-tighten the control arm bushing bolts.

 

[gaerisch]

The car was on jack stands when I did the rear shocks. But I remember dropping the rear axle to fully extend the shocks. The jack stands were on the frame of the car not the axle. So I’m guessing the control arms are getting suspension wind up as you call it.

 

[General karthief]

When you get it back up on the stands make sure you inspect the control arm bushings, you may have worn bushings and when you let the rear housing droop to install the shocks the worn bushings tore loose, like wmburns said, check bump stops for damage.

 

[gaerisch]

Thanks. I plan on replacing the rear upper and lower control arms. Only makes sense if I damaged the bushings. This time I’ll make sure the weight of the car is on the suspension before I tighten the bolts on the control arms.