Is there a proper way to adjust the rear toe on a first gen? I read in one thread to loosen the three bolts holding the trailing arm to the car and adjust there, but is there a way to do it more fine tuned? The only thing I can imagine when I read that is to loosen it and smack it with a rubber hammer until it's close to what you want (doesn't sound as precise as I'd like).

 

Just did a search for alignment (looking for recommended specs) and came across a thread which said to do basically what I imagined: loosen bolts just barely, smack with rubber hammer, check toe settings, repeat as necessary, tighten back.

 

Loosening the bushing bracket bolts and moving the trailing arm is the correct way to adjust toe. Whacking the tire with a fist or mallet may or may not be required. The issue to be dealt with is changes while tightening the bolts, so, sometimes the bolts need tightening to hold the bracket in place and then a ballistic strike to shift the arm if bolt torque causes deviation while tightening further. There is a tool that is supposed help with adjustment, and hold position while applying torque, but it doesn’t perform very well. Once you witness the operation you will realize the amount of micro-adjustment (hundredths of a degree) that can be obtained.

 

For proper adjustment you'll need a set of adjustable control arms.

Here's a link for some goodies:

http://www.helix13.com/mini/products/suspension-chasis

 

I thought that the control arms are not really to be used to adjust toe, just camber. I believe that the proper way to adjust toe is at the trailing arm.

 

On an R53, adjusting one affects the other.

 

After installing some H-Sport springs, I reset the camber on my 06 and noticed what looked like a toe adjustment at the base of the trailing arm. Then while browsing my new Bentley I found mention of a toe adjustment tool (P/N 324200, 83300494002) looks kinda like an offset 1/2" drive socket. It's $ 49.88 at ECS Tuning.

 

One adjustable control arm per side (lower) allows camber adjustment. Two adjustable control arms per side also allows toe adjustment - loosen the trailing arm bolts.

Alan

 

True for the front, not the back.

Alan

 

toe should be adjusted by loosening the front bracket on the trailing arm, whether or not you have adj control arms. control arms are for camber adjustment. if you have upper and lower control arms, adjusting both in and out will affect rear TRACK (distance between wheels) which can be useful for clearance issues in the rear. while it is true that adjusting camber AFFECTS the toe, you can't just adjust rear toe without changing the camber along with it if you only use the rear control arms.

 

Please read some of the many previous threads on this exact topic. While it is possible to adjust toe with the upper control arm while adjusting camber with the lower (interactively) as sonichris points out, this is NOT A GOOD IDEA. Look particularly for posts by one very knowledgable NAMer named meb -- he provides the straight dope on this.
Rule: buy one set of adjustable control arms, install in lower position. Adjust camber with arms, adjust toe with loose bolts and rubber mallet.
Drive...

 

until somebody shows the math, i claim this is an urban legend. if he does, i'll withdraw my scepticism.

i have adjusted my toe and camber several times with just the control arms. doing it that way you can always get back to exactly where you stated in case you mess up.

once you move the fwd trailing arm location, how do you get back to where you started? mark the frame?

 

Aligned the car last night; adjusted toe using the method of loosening the bolts and adjusting with a "precision tool" . Thanks for the info, everyone.

I don't have the numbers for the lengths / mounting locations of the rear suspension but I can promise that changing the lengths of any of the arms back there will change the kinematics of the suspension and therefore change the toe / camber curves of the rear. Even adjusting camber via the lower arm only will change the curves. I can't say how much it would change them (probably not much), but I'd rather change as few variables as possible, especially via methods designed by BMW (lower to adjust camber as in the 05+ and adjusting toe via recommended method).

 

...one change at a time

I've played with the back a lot over the 150,000 miles, though I have not lengthened both upper and lower control arms in sync...I wonder what that might offer, or not...I suspect that at some point the trailing arm bushing will cease to work...

 

i was looking at the rear suspension the other day on the lift. adjusting both upper and lower control arms longer at the same time will increase the track while increasing toe in, since the entire rear arm is pivoting around the front compliance bushing. so you CAN adjust toe with two control arms, BUT you will also be increasing or decreasing the rear track. this can cause clearance problems if your car is lowered and are running wide tires, like me.

the ideal way to align the rear with four control arms is to set the rear track and camber where you want it with the arms, set the front toe as close as possible by sliding the front mount, and then perhaps use both arms to zero in the rear toe the last few hundredths of a degree.

 

anyone got an underside pic of the 3 bolts to loosen for toe adjustment?

 

I do not have an actual picture because you can not even see or touch them on my GP because the body panels cover the bolts. But I believe the three bolts go into the three slotted holes on the mount shown as Item 7 in the realoem figure.

 

Yes.

I replced both of these bushings last spring and noticed no difference. I had about 120K miles on the car.

A note about rear track changes and camber because it was mentioned above...all else equal a wider track will decrease camber compensation. Plot stock values for every .5" - 1" of travel and then see where these go with a wider track - the change in the toe/camber curve is interesting.