1996 80 Series rocking back and forth freeway speeds (1 Viewer)

[Pascoscout]

Can't imagine bushings going from being okay to having sway just in the time to change shocks. Suppose one could fail completely but seems like that'd be easy to spot.

Did you run 35psi in the tires prior to the shocks? If I run mine that low the truck sways a bit on the highway. Usually go at least 40psi when I air up after a trail run and then go to 50psi when I get home to the big compressor. Have you tried a higher pressure to see if it makes any difference?

Is it possible the shocks are bad? If they sit the wrong way on the shelf too long the oil can leak past the seals and they won't work right even though they are "new".

 

[ajax1]

Are the rear plates the rear shocks bolt into up top on there right side? The plates are easy to install to the opposite side by someone and not know any better.

 

[shotguntet]

Thanks for the input. I will try bumping the air pressure up and see what happens. As for the shocks I can warranty them. One shop suspects its the rear shocks so I am considering trying it out with the rear set.
Is there any way to tell if the plates at the top are swapped? Are they labeled to designate what side they should be on? If visible without disassembly then I can try to have the shop fix their maistake at their expense.

I bought new sway bar bushings both front and rear to see if that has any effect.

 

[Pascoscout]

Thanks for the input. I will try bumping the air pressure up and see what happens. As for the shocks I can warranty them. One shop suspects its the rear shocks so I am considering trying it out with the rear set.
Is there any way to tell if the plates at the top are swapped? Are they labeled to designate what side they should be on? If visible without disassembly then I can try to have the shop fix their maistake at their expense.

I bought new sway bar bushings both front and rear to see if that has any effect.

I do believe the plates are stamped with an R or L for the sides but you may have to remove them to see it. Personally I think it'd be pretty hard to get them wrong, when backwards it puts the shock at a weird angle and it would take some effort to get the bottom mount on.

 

[LandLocked93]

One thing I noticed on my truck that absolutely moved the bushing from 'ok' to 'au-crap' instantly was directly after a shop visit to rebuild the transmission.
Vintage original 1993 bushings, following a lengthy, full suspension droop at the shop, stressed the already crusty buggars beyond their decades-old normal range of motion. So yeah. It *can* happen.

 

[shotguntet]

Hey all, quick update. Replaced the coils with new stock (claimed 1/2" front and 3/4" rear lift) height OME's. Problem solved. Actually raised the front by 1.25" and the rear by 1.75". Much lot bumpier ride than before but no more rocking left to right. Thank you to everyone for their input.

 

[PolarRunner]

Just came back from a camping trip in the Catskills this past weekend. On the highway I experienced the same behavior. Randomly, seemingly without cause, my 80 started to rock left and right. I feared it was the front panhard bar (I had the bolt come out on the highway back in '17, that was scary) because the behavior of the cruiser up until when the bolt came out was similar to this. The bolt is still tight and secure.

Nothing suspension related has changed since my last long freeway run.

With over 280k miles on the clock, an age of 26 years and unknown maintenance history, I can almost guarantee all the rubber is shot.
For anybody on here to think the rubber bushings on these rigs are still good, after this many years are sadly mistaken. Unless the vehicle was kept in perfect conditions during storage, that rubber is surely shot.

The movement reminded me of when you see a car with blown shocks go over a bump and the rear keeps undulating up and down because the rebound is shot. Just in a left to right movement. I'm convinced the factory rear shocks aren't helping at all. I think my springs are worn and tired as well.

I'm going to start replacing rubber underneath.

 

[deltapine1]

I chased this issue when I purchased my 80. The best way I can describe the situation is the rear slightly sways. Slightly in that you cannot see the actual motion when following the vehicle or looking in the rear view but it is felt.

My 80 has 3" of lift and TJM shocks.

None of the following fixed it: Wheel bearings, front axle rebuild, new tires, Radius Arm Castor Correction Bushings, Alignment, rod ends, anti-sway ends and bushings replaced, replaced stock radius arms (with TJM castor correction bushings) with DVS radius arms.

I added a DVS Rear Pan Hard Bracket and it helped a little but the sway was still present.

Had the rear upper and lower link bushings replaced with White Line bushings and it went away.

My rear bushings on the suspension links were cracked badly on the Driver Side. The Upper was the worst. Again I have a lift; it is hard to believe stock height 80's would have this issue.