I've been reading all the previous alignment threads but I just have so many questions I think it would be better to just start a new thread. hopefully some of you more experinced with alignment problems can help me out. Here are the numbers after the alignment (left side numbers then right side numebrs):


Caster: 4.6 5.0
Camber: 0.5 0.3
Toe: .05 .05


Left Rear Camber: 0.0
Left Rear Toe: -0.15

Right Rear Camber: -0.2
Right Rear Toe: 0.25

Total Toe Front: 0.10
Total Toe Rear: 0.10

Front Set Back: -0.2
Thrust Angle: -0.2

Camber Difference Front and Rear: 0.2
Caster Difference Front: -0.4

The front wheel specs are all withen range but what is going on with the rear? the left rear has negative toe and the right wheel has almost the exact opposite positive toe. Is this indicating the axle is not sitting perfectly straight? Also why does the right rear have a -0.2* of camber?

What exactly is the set back angle? i notice that my thrust angle is -0.2 (is that enough to cause a drift?) and the set back angle is the same. is this to "cancle out" the thrust angle? also what does total toe refer to?

sorry for all the questions, trying to figure out why its drifting over to the right. i need to hold the wheel to the left to get the car straight on most roads. its not much but if i completely let go of the wheel it will travel to the right pretty easily. the guy that did the alignment said he thinks the steering box is worn which could be, but i think something may be off with the rear axle.

What do these numbers indicate??

 

any ideas? i rotated my tires and it helped a little, then i barely nudged the set screw on the steering box a little. moved it very little and it seemed to help just a little bit. im afraid to move it any more without first finding out more about it.

but does anyone see anything in the alignment numbers above that indicates something wrong with anything? especially the rear axle. i assume any problem with the car drifting is in the steering box or some worn suspension component i havent noticed yet, unless it looks like its the rear by looking at the numbers.

 

Setback is when one front wheel is set back (towards the rear of the car)farther than the other. It is usally caused by the manufacture building it that way, or a collision. on our cars you can change setback by taking the subframe bolts lose and moveing one side front or back accordingly. If you have negative setback move left side up and right side back. if positive, do the opposite.
Thrustangle is the direction your rearend is turned off the centerline of your car. so its kind of pushing the car at an angle. if your thrustangle is off .25 degrees + or - it could cause the tires to wear, car to pull, and steering wheel to be off center. I don't know of any way to adjust it from the factory but there has to be something aftermarket. You might want to go to a body shop and have them check the "frame " for damage.
You could also have a problem in your brakes. You could have a caliper locked up, a guide pin stuck, or a collapsed hose. I would check that first, just take the wheels off and see if the pads are wearing evenly. hope i helped

 

front looks fine. shouldn't cause any drift or pull right.

in this thread i explained thrust angle and drew up a pic.

https://www.thirdgen.org/techbb2/sho...t=thrust+angle

very doubtful the rear thrust angle is causing the drift even though it is pointing left. which would cause the rear to swing left and point the car right. you can fix this with adjustable trailing arms from BMR or spohn.

when you rotated the tires, did you do front side to side, front to back, etc? does it pull right when braking also? how's the wheel bearings?

 

I rotated the tires front to back and criss crossed them, LF went to RR and RF went to LR. it doesnt pull unevenly when braking. Havent closely examined the wheel bearings but thats the next thing i check.

 

if it's a slight drift, take it back and ask them to either add about .2 more caster to the right. or subtract .2 caster on the left. and bring the camber to 0* on the right. that should take care of it then.

make it look something like this:

camber 0.5* 0.0*
caster 4.5* 5.0*
toe 0.05 0.05

 

i dont know how to quantify the drift; sometimes its bad and other times u cant even feel it. depends a lot on the road and speed i find. the drift is more apparent at lower speed.