93 Grand Prix sagging after strut change

[cdefn]

I have recently changed the struts on a 93 grand prix. I aquired it with broken rear struts. before i changed the struts, the rear tires did not rub. after changing the struts, when i hit a bump the rear tires rub. is there something that might have shifted or moved while i had it apart? 

[55trucker]

What is it that the tires are rubbing up against?.......you should be able to see some sort of wear mark in the wheelhouse which the tires are coming in contact with...

 

Did you properly set the wheels camber back to where it is supposed to be?

[cdefn]

they are rubbing the inner side of the fenders, outside of the tire. I read something in another post about setting the camber in another post after posting this. what is the best way to set the camber properly?

[pitzel]

Loosen the strut to knuckle nuts, but do not remove bolts.  Place a hydraulic jack underneath the knuckle (bottle jack or floor jack will work).  Jack the knuckle up as much as needed to fully move the camber into being proper.  Tighten strut to knuckle bolts to spec.  Remove jack, repeat on other side.

 

I don't know why you'd get rubbing though, even if the camber was set horribly.  Can you take some pictures and post them?  Perhaps your leaf spring is overly worn.  In which case, you might be able to use those Moog K6544 pucks to get another cm or two of height and avoid rub, but you really should be looking at replacing it if its in that bad of shape.

 

What kind of struts, BTW?  I ran into the issue with the KYB's, but mainly cause they use oblong/elliptical holes, rather than circular holes. 

[55trucker]

 what is the best way to set the camber properly?

*properly* would be to now have the camber set at an alignment shop.

 

To do the job properly yourself would see one having one of these gauges onhand before one gets involved with the job.

 

http://images.ffx.co.uk/tools/GA45.jpg

[pitzel]

*properly* would be to now have the camber set at an alignment shop.

 

To do the job properly yourself would see one having one of these gauges onhand before one gets involved with the job.

 

http://images.ffx.co.uk/tools/GA45.jpg

 

Nah, there's really not much to camber setting on these cars.  Camber on these cars is 'changed' by elongating the holes that the strut to knuckle bolts go through, and applying forces accordingly to get things in place before tightening.  There's very little adjustment that can be done otherwise. If adjustment is needed, the only way to accomplish such is to use a grinder and actually modify the strut, and the aux spring/stabilizer bar mount per the manual.

 

Chances are, the OP bought a set of struts which had the mounting holes pre-elongated, and simply needs to do what I described to get everything lined up before tightening the nuts down to spec.

[55trucker]

I don't share your position on the subject, how can one possibly expect to get the camber back to specs if one doesn't have the proper equipment onhand to do the job,using anything other than a proper gauge is a shot in the dark

[cdefn]

adjusted the camber to where sitting on the ground, the wheels are straight up and down. yes, the rear springs are a little weak, but they are not rubbing now. Plan on getting to alignment shop after putting front struts on in about a month.

[RobertISaar]

service manual says for 93, rear camber should be +.1*(+/- .05*), so if you have them perfectly straight, you're only .05* out of specification, and it's at least more negative rather than positive camber, I doubt you would be able to see that in tire wear by the time they get replaced, let alone only a month of driving.

[pitzel]

I don't share your position on the subject, how can one possibly expect to get the camber back to specs if one doesn't have the proper equipment onhand to do the job,using anything other than a proper gauge is a shot in the dark

 

The only way to change camber on these cars is to grind at the bottom hole on the strut per the service manual.  The only way things could get out of alignment, camber-wise, is if the new strut came with an oblong hole instead of a round one.  This is the case for the KYB's.  I gave a procedure to place appropriate forces on the assembly to align the strut properly to a position where the bolt most closely resembles what was removed (ie: at its most negative camber-possible position, which is basically straight)

 

 

adjusted the camber to where sitting on the ground, the wheels are straight up and down. yes, the rear springs are a little weak, but they are not rubbing now. Plan on getting to alignment shop after putting front struts on in about a month.

 

There's nothing in doing the front struts that changes the alignment either on your car.  Assuming all you're doing is replacing the strut cartridge through the strut tower using the W-body tools.  See my previous post with that video.  I'm not against alignments, but they're mostly relevant for steering work on these cars unless the car isn't steering straight or the body has suffered an event causing frame distortion.

[cdefn]

 

What kind of struts, BTW?  I ran into the issue with the KYB's, but mainly cause they use oblong/elliptical holes, rather than circular holes. 

They are Monroe, and they had long holes

[cdefn]

 

 

 

 

There's nothing in doing the front struts that changes the alignment either on your car.  Assuming all you're doing is replacing the strut cartridge through the strut tower using the W-body tools.  See my previous post with that video.  I'm not against alignments, but they're mostly relevant for steering work on these cars unless the car isn't steering straight or the body has suffered an event causing frame distortion.

 

Couldnt find your video

[cdefn]

Loosen the strut to knuckle nuts, but do not remove bolts.  Place a hydraulic jack underneath the knuckle (bottle jack or floor jack will work).  Jack the knuckle up as much as needed to fully move the camber into being proper.  Tighten strut to knuckle bolts to spec.  Remove jack, repeat on other side.

 

I don't know why you'd get rubbing though, even if the camber was set horribly.  Can you take some pictures and post them?  Perhaps your leaf spring is overly worn.  In which case, you might be able to use those Moog K6544 pucks to get another cm or two of height and avoid rub, but you really should be looking at replacing it if its in that bad of shape.

 

What kind of struts, BTW?  I ran into the issue with the KYB's, but mainly cause they use oblong/elliptical holes, rather than circular holes. 

was wondering about putting the Moog Leaf Helper Spring K6000 on to help the rear springs, has anybody used these. 

[pitzel]

They are Monroe, and they had long holes

 

Yeah, just like the KYB's.  They strut to knuckle bolt, unless you do what I described with the hydraulic jack, will tend to move to an alignment to the inner, not the outer part of the hole.  So basically if you do the jacking as described, it will re-align the bolt to the other side of the long hole.

 

As for the front strut video:  http://www.w-body.com/topic/53905-front-strut-video/

[White93z34]

Nearly 100% of the time a sagging 1g means worn out leaf spring.

 

Its possible that the camber is out just enough to allow the tire to impact the wheel arch. But regardless that should never happen in the first place.