Rear Alignment question

[Crab]

I have just replaced the old steel leaf spring on my 1980 with a fiberglass mono leaf spring by TRW, also installed KYB gas shocks. Will this in any way change the rear alignment?:confused I don't think it will, am I right or wrong? Thanks!!!

 

[wishuwerehere82]

It should not change the rear alignment since you didn't change caster by replaceing the springs and shocks. But your body ride height will probably go up a little if you used the original spring bolts, and that raises the pivot point on the frame for camber. If you rear wheels look like they are tipping in a little, get a 4 wheel alignment done. They should be close to 0 degrees.

 

[Crab]

Oh yes I do have a slight ride height problem, it's at about 29.5" . I'm going to drive it a few hundred miles to see if it settles down some , then use longer 10" bolts to adjust height.

 

[Chiller]

I also just replaced my steel spring with a fiberglass one. I took my vette around the block and now it has a metalic clunk from the left rear when you first start out. I did not have this before hand. My question is as you look at the vehicle from the rear, should the spring bolts be tilted in? If I recall correctly,when the steel spring was on there the bolts ran straight up and down. Any help on this will prevent me from loosing my sanity.
Chiller

 

[wishuwerehere82]

I also just replaced my steel spring with a fiberglass one. I took my vette around the block and now it has a metalic clunk from the left rear when you first start out. I did not have this before hand. My question is as you look at the vehicle from the rear, should the spring bolts be tilted in? If I recall correctly,when the steel spring was on there the bolts ran straight up and down. Any help on this will prevent me from loosing my sanity.
Chiller

Chiller,

Are you sure the spring is centered in the center mount. If the bolts are not really torqued down the spring can shift from side to side. I get that "boing" sound every once in a while too.

 

[Chiller]

The bolts are torqued down to 40-45 ft.lbs (as per Vette Brake Products instructions for 78-79 vettes) It's a thick metal to metal sound. At first it was not there than it became more common. I will look at it closer when I get off work.

Chiller,

Are you sure the spring is centered in the center mount. If the bolts are not really torqued down the spring can shift from side to side. I get that "boing" sound every once in a while too.

 

[Vettehead Mikey]

Your 'clunk' sounds more like a front snubber bushing or a universal joint.

The load on the rear spring does not change when going from reverse to forward direction.

 

[gmjunkie]

If your ride height is Higher or Lower on Rear, it Will Change your caster,Camber and tow on Front!! junk!!

 

[Chiller]

Alignment

I guess that I'm "spacing" How would alignment on the front cause a clunk on one side in the rear ?

If your ride height is Higher or Lower on Rear, it Will Change your caster,Camber and tow on Front!! junk!!

 

[gmjunkie]

I guess that I'm "spacing" How would alignment on the front cause a clunk on one side in the rear ?

It Won't,The Clunk is a bad Bushing in Trailing arm or arms,Diff.snubber Bushing, or Bushing's in Spindle rod's,or U-joint's!! When you raise or lower the rear it makes thing's run at differnt angle than it is used to, old bushing's that are weak from age are at deffernt angle and can come apart!! or was alredy coming apart and the added stress finish's them off!! Old U-joints that have been run at one angle will have little worn places from needle bearing's in cap's and U-joint shaft and when you change the angle it makes them run on high and low spot's making Clunk's,Vib's and unwanted noise!! And it will not be long before the needle bearings are ground up!! Now Aligment when you raise the the ride height on rear it will change the rear Camber more Pos. and make the rear tow more Out. when you lower the rear it will change the rear Camber more neg. and make the rear tow more in. 3/4 in. up or down will change Camber and Tow enough to ware Tire's and Drive Funky!! Now how will this efect front simple!! If rear is up it will change Caster angle Top ball joint will go forward, Bottom ball joint will be more backward, makeing less pos. Caster!! and this will make more Pos. Camber and change Tow in more!! If you were here I would take you out to the Rack and Show you How it work's I can explain and show easer than I can Type and Spell!! That's why I don't wright Repair Manual's junk!!

 

[Chiller]

Thanks GM JUNKIE. I will have to look at everything and I'll keep you posted.