Rear driver side sag

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texasmike

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I recently had the coils replaced and that helped but I still have about a 1/2" sag in the back. Has anyone tried blocking or shimming the leaf spring to fix the problem? Is that a good way to go and would it affect drive-ability in any way?
 

Octane

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I recently had the coils replaced and that helped but I still have about a 1/2" sag in the back. Has anyone tried blocking or shimming the leaf spring to fix the problem? Is that a good way to go and would it affect drive-ability in any way?
Sounds like the springs arch collapsed.I took mine in to a shop and had it re arched.
 
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Craig 85

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I've had 2 Suburbans lose their arch on the R/R. I always assumed it was due to the the torque from the 454's that were in the trucks. One thing to check is the length of your springs from spring eye to spring eye. My were almost an inch longer on the right due to the sag. This caused my truck to crab walk.

If you just add a block to a spring in this condition, your truck will still crab walk and handling/steering will be affected. Either re-arch or get new springs.
 

Grit dog

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I recently had the coils replaced and that helped but I still have about a 1/2" sag in the back. Has anyone tried blocking or shimming the leaf spring to fix the problem? Is that a good way to go and would it affect drive-ability in any way?
1/2”?
That ain’t much. Bet you measure 9 of 10 trucks and they’re off by that much or more.
Heck I was just looking at our “new” truck and it looked a bit off. It’s 1/2 to 3/4” different side to side. Old truck was too, since new. The ‘86 is slightly different.
I wouldn’t sweat it as long as it’s only that much and you make sure no cracked leafs.
You could try a mild re-arch at home if it bugs you. (Stuff like that bugs me too.). Jack up saggy side by the frame, let the springs droop. Fit a jack in between the frame and axle and crank it up. Be careful jack can’t slip out under pressure.
Disclaimer I haven’t tried this for these purposes, but have jacked up a couple trucks stuck good in mud and by the time the wheels popped free, the rear springs had been re-arched.
 

Grit dog

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Agree w Craig, don’t try blocking or shimming.
 

Swearbody

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I had this same issue on my 86 longbed. i had the HD spring pack(7 leaf vs 3) from a previous truck sitting in the shop so I took the base spring from the hd set and it solved the issue. I am referring to the bottom-straight-ish and short thick spring that is the base for the hd springpack

Also how are your bushings in the springs. A bad bushing on one side can cause a 1/2" easily...from experience.


Ok so I just realized you are referring to a side to side lean so the spring pack would only help to lift BOTH sides.
The bushing however is still a viable solve,lol
 
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texasmike

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Thanks everyone, I'll most likely re-arch or replace them. Who would be the best vendor to buy from?
 

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