Changing spring seats

[JRL]

YES
Matt, you're wrong.
You can mark the strut and try .... to mount it exactly to the mm the way it came out, but in reality unless you hit it dead on the nose, (maybe a 1 in 20/40 shot), you need an alignment after the spring seat(s) is/are installed.

Also if you have a very worn or broken spring seat your alignment is already out and you need to align it.
Recommend you do both. If it's broken the other is soon to follow and this way only one alignment is needed and be done with it for a long time.

Also consider new struts. If your struts have over 100K miles, they're shot anyway!
(Labor is the same)

[matthew1]

I've had no uneven tire wear since. Just saying.

[JRL]

I've had no uneven tire wear since. Just saying.

Then you lucked out but it still is probably a hair off

[precopster]

The P2s have a elongated upper hole on the strut tower. This adjusts CAMBER ONLY. On P2s according to Vida you can measure the upper knuckle distance to strut by means of a vernier caliper and reproduce that when re-assembling. Caster and toe-in are affected by other suspension geometry and tie-rod adjustment positioning.

On P80s camber is fixed (unless you have installed a camber kit) so no adjustment is necessary upon strut removal UNLESS your 2 knuckle holes for the strut have become elongated through time and wear. A quick check with a vernier on BOTH of these before disassembly can note the measurement which can be reproduced upon re-assembly. Again this ONLY affects camber.

Alignment shops can't adjust castor. Castor is a factor of toe-in and camber. They can adjust ONLY toe-in AND camber on P2s if they use their ALL-DATA or other reference.

On P80s they only adjust toe-in unless they're specifically instructed that the knuckle distance is to be checked or if a camber kit is installed.

A spring seat can't affect alignment as it only controls the angle of the spring itself if it's torn, NOT the angle or placement of the shock tower.

[erikv11]

I always thought the whole point was the three nuts on the top of the tower, which very much affect the angle of the tower. Unless you replace them in EXACTLY the same position, toe is altered. Hence, if the tower comes out, alignment needs to be checked.

[precopster]

Alignment technicians make changes to the car's settings with the weight of the car fully on its wheels.

If those three nuts provided more than a fractional adjustment (if at all) in camber or castor the car's hood would be raised and the weight of the vehicle would be lifted by a hoist to allow those three nuts the abilty to be moved.

Then after this minor adjustment is made they would need to drive the car to allow the gas shocks to settle the ride height to allow an accurate re-measurement. Next time you replace tyres ask an alignment technician if he adjusts camber from under the hood on production unmodified cars; he will have a quiet chuckle.

Only camber-adjustable racing style bearing plates can be adjusted with the weight of the vehicle on the front wheels.

[erikv11]

I'm not talking about why techs don't use the three nuts for adjustment. I can think of plenty of reasons for that, too.

And by toe I meant toe, not camber.

[precopster]

There is NO adjustment on the bearing plate not for camber and especially not for toe and tomorrow I'll prove it to you but right now gotta get some shut eye.
In the meantime you can have a peruse at the attached document from Vadis

[drgswede1978]

Hi. Done this job today took about 1&1/2 hours in all.Thank god I've got air tools at home. It was the spring seats that were shot. They had a 97 date stamped on them so must of been original. Thanks for all the help.