steering and suspension Sagging In The Rear

[devotion]

Got the kids 76 up and running...like a champ! When we jack the rear of the car up, they lay it back down, it sits level...after driving for a while, it sags a couple inches on one side.  My first thought is worn out spring...but only on one side?

[M3M3]

what is the condition of the car?  rusty at all?  look at upper spring perch, rear shock tower, subframe to body attachment point, etc.  

[devotion]

Super solid

[Maximillian]

If the bushings are new and solid and there are no issues with the subframe and trailing are, then Its the spring. They commonly wear and produce that result.

[Mike Self]

Is it sagging on the driver's side?  Perhaps there was a, shall we say, hefty-sized PO driver?  That will evenually lead to spring sagging.  

 

You might also take a look at the upper spring mounts (the rubber ones) in the back.  They come in three thicknesses, denoted by concave dots in the rubber.  Make sure the mounts have the same number of dots on both sides.  A PO may have replaced one, not realizing that different thicknesses were available.

 

mike

['76mintgrün'02]

When we jack the rear of the car up, then lay it back down, it sits level...after driving for a while, it sags a couple inches on one side.

 

 

 

I have read several threads lately suggesting using silicone grease to install trailing arm bushings.  As I understand it they are a sort of rubber 'torsion bushing', not meant to spin in their mounts.  This is why it is important to tighten their through bolts with weight on the suspension, which sets neutral torsion at rest.  Then the rubber twists/returns with trailing arm rotation.  Could it be that the bushing is twisting/slipping under stress and then not returning on that side.  When you jack the car up it gets spun back "up" until after a few good jounces on the road.  Slipping/sticking combination due to greasy bushings?  Just a guess.  

 

I plan on trying slightly soapy alcohol mix when I put my bushings in... just in case.

[jerry]

i'm sagging in the rear too...

[Koblenz]

i'm sagging in the rear too...

Exercise perhaps?

[remmib02]

After checking for the one, two or three dot upper spacer, measure height of both springs while the car is on ground.    If factory paint codes are still present on springs, verify they match.  Refer to blue factory manual for the color/coil rating.

[allbim]

i'm sagging in the rear too...

Just on one side?

[M3M3]

Exercise perhaps?

LOL!

[Hans]

Also check the "top hat" mount where the spring sits on the trailing arm. They rust.