How do you know when your body mounts are bad?

[wazzabie]

How do you know when your body mounts are bad?

[James Lamb]

Have not been on the forum in awhile, just seeing this, so you've hopefully replaced those things by now. If you have a square body truck they are now 30+ years old, and trust me, they are bad.

I've just replaced the ones on my '89 Suburban. After years I finally found the weird metal on metal noise I keep hearing at odd times - that's now much the gem rubber was compressed. Some of the mounts were like old rubber bands left in the sun, not only deflated, but stuck to the steel inserts like glue.

And it does make a noticeable difference to the amount of rattling. Was not as bad to replace as I expected, except for the one near the rear tire where the captive bolt was 1/2 rusted through. Replacing that was a little more work.

[wazzabie]

Originally Posted by James Lamb

Have not been on the forum in awhile, just seeing this, so you've hopefully replaced those things by now. If you have a square body truck they are now 30+ years old, and trust me, they are bad.

I've just replaced the ones on my '89 Suburban. After years I finally found the weird metal on metal noise I keep hearing at odd times - that's now much the gem rubber was compressed. Some of the mounts were like old rubber bands left in the sun, not only deflated, but stuck to the steel inserts like glue.

And it does make a noticeable difference to the amount of rattling. Was not as bad to replace as I expected, except for the one near the rear tire where the captive bolt was 1/2 rusted through. Replacing that was a little more work.

Did you use the poly mounts or the stock style mounts?

[James Lamb]

I used polyurethane ones. I've seen all the arguments for and against polyurethane. Honestly, you could put a ham sandwich in there and it would work better than 30+ year old rubber. Main reason I went with urethane is they are designed to not need the internal metal supports the rubber ones used, and which are both highly corroded and semi-permanently bonded to the old nasty rubber. You reuse the large concave "washers" that are on top of a few of the mounts like the ones on the sides under the doors, and my kit came with new large washers for the others. I had to order 4 bolts from LMC Truck as some of the bolts were very badly rusted, and the bolts are not all the same.

It made a marked improvement in ride quality. The teeth-rattling jar when hitting a bump on the highway is gone. And I had already replaced all the springs and all the shocks. Surprising how much difference it made really.