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Caster setting

4.6K views 13 replies 10 participants last post by  Chilly Palmer  
#1 ·
hello. so i just replaced my strut mounts on a 04 GTO and had the car realigned. Spec sheet shows the final caster on the right side set to 9.42 degrees, left at 8.32 degrees. Camber and toe are within OE specs. Is the right side caster too much? This car is just street driven.

In addition now I am hearing a slight thunk when making hard right or hard left turn. I may have left something loose which I am looking over this weekend since I am changing the brake pads. Any thoughts what it might be besides something being loose or not torqued enough.

Thanks.
 
#3 ·
Shouldn't the caster on both side be pretty close? 1.1* off is a lot.
 
#4 ·
i think the caster on the right side should be just a bit more for the road crown, but not sure
 
#5 ·
There is an extra 4mm washer that is added behind the driver side RR bushing for this purpose. I had no idea until I did the RR bushings and asked a friend why it was like that.

Now will that throw the caster off that much, I don't know?
 
#7 ·
I have 9.5 caster L and R.

I'd replace the Radius Rod bushings if you haven't.
 
#11 ·
The factory didn't put that washer there for decoration, lol. I have my Lovells set to +1/2 degree on top of the factory washer on the left side. No pulling issues noted, however I wish i had the clearance to run 3/4 to 1 degree over stock. As it is, I'm running the right front wheel well just a touch.
 
#14 ·
The factory didn't put that washer there for decoration, lol. I have my Lovells set to +1/2 degree on top of the factory washer on the left side. No pulling issues noted, however I wish i had the clearance to run 3/4 to 1 degree over stock. As it is, I'm running the right front wheel well just a touch.
You probably do have the clearance, just need to pull back the passenger-side fender liner.

I increased my caster on both sides by +3/4* when I put in the Lovell's RR bushings, and love it. I rubbed at first, but it was because I was missing a bolt at the bottom of the plastic fender liner. Zip tied it and haven't rubbed since. :)

EDIT: I'm on stock 17's with 245/45's, so wheel/tire diam is normal. Larger wheel/tire diameters may not have room.
 
#12 ·
I installed radius rod bushings and had the caster set the same on both sides. Not a single problem noted. Even got rid of my fender lining rub on the passenger side.
 
#13 ·
An ideal cross caster is around .3 to .5. The 1.1 difference is a bit too much and if the casters are equal there may be a tendency to pull in the direction of the crown of the road as stated above.