I've always heard that you should make alignment adjustments with the car on its weight.

So when you bring your car into the shop for an alignment and they put it up on the rack, how do they loosen the four bolts in the rear to adjust the rear camber and toe with the wheel in place? I can't see any way to do it.

Unless they pull off the wheel, loosen all the bolts, put the wheel back on, and put it up on the rack. Then after the adjustments are made (you can probably tighten the two eccentric bolts with the wheel on) bring it back down, pull the wheel off again, and tighten everything up.

Does anyone have any experience with this? I know, its a bit of a weird question.

 

I have never watched how the pros do it, but I have done my own 'home' alignment.

I measure the wheel for camber & toe with the car on level ground. Then you determine what you need to change to meet your goal. Another 1/16" toe in for example. You have to convert everything to linear measurement. Then lift the car, remove the wheel & measure again to get a 'before' measurement using the rear brake disc as your reference.

Loosen the required bolts - toe & camber lock bolts & the 2 bolts to the trailing arm so the springplate can move vis à vis the arm. As you turn the adjusters, you can see it all move. Just dial it in to your 'after' adjustment. Re-assemble everything. Drop the car & drive it around the block, measure again & start the whole process over.

Imho, it could not be done with the wheel on. But I'm open to suggestions.

Ian

 

Professional alignment racks allow for the required access from under the car; much easier than the do it at home method! I know that Ian has done it, and I also did it because I was looking for a problem on my race car and at the time didn't trust anybody.

 

Even with access, how do they loosen/tighten the trailing arm bolts? You need a wrench or socket on both sides - bolt end & nut end.

Or is just the normal Porsche pretzel position? You know, the one where you pretzel your body into strange contortions to reach into THOSE areas?

Ian

 

Ian: Most guys use an impact wrench to break the hardware loose, then throttle down the wrench to re-snug, then torque. It all comes down to tools, tools, tools - and being a pretzel certainly helps!

 

To undo the rear trailing arm locking bolts, I used to use a Snap-on 3/4" (19mm) - 1/2" drive torque adaptor. This allows better access for the breaker bar and extension when adjusting alignments on a rack.

 

But how do you hold nut or bolt on the other side with the wheel in place?

 

That's the pretzel part, and having a wide variety of high quality box/open end wrenches!

 

You can use either a flat box wrench or combination.

If you know the alignment is out and don't want to know the actual settings; loosen all the fasteners first.