New Shocks, Now New Knock/Clunck Over Bumps

I’ve just installed new shocks on my 1997 Suburban K1500 4WD. Now there’s a knock that appears to come from the driver’s side. The knock seems to be as the wheels descend while crossing rolling bumps rather than abrupt jolts; for example; pot holes or running over reflectors imbedded in the road don’t cause the knocking.

Here’s what I’ve checked: balljoints, inner and outer tie rods, idler arms are OK; brake calipers secure; 4WD is fine; steering shaft is OK (don’t feel the knock in steering wheel); can’t find anything loose.

I’m stumped…anyone got any ideas?

Try tightening the clevis mount on the drivers side front shock. It sounds like it is not quite tight enough. The shock makes more damping load in extension and the round eye-type clevis mount needs to be pretty tight or it will slip and make a clunk. Abrupt jolts make enough other noises to overshadow the clunk. Try about 1/3 a turn more on the nut.

Check the sway bar end links and bushings for wear.

Those components take a beating with worn shocks.


Thanks, guys. I checked the mounts for both new shocks. The left was tight (no play), the right had a little play, so I tightened it. Took it out for a test drive, no love, clunk is still there. Normally, I would agree that there are other noises from abrupt jolts would cover it up, but there’s no hint of it at all on the embedded reflectors. It’s strong enough on its own that it would cut through a little bit.

The sway bar links are less than two years old, but checked anyway and they’re solid, no play in them at all.

Thanks, again. I’ll keep working it and post if I find out what it is.

Can you get a couple of friends to bounce it while you get on the ground and listen/look under to see if anything is moving that shouldn’t?

Have you considered that one of the “new” shocks you just bought is bad from the factory? If you took off the LF shock and drove it (carefully) would it quiet down?

How about the sway bar bushings?


Thanks, again, guys. We’ve bounced on it, but haven’t been able to recreate the noise. The sway bar frame mount bushings do look suspect, the links are good. I bought new frame mount bushings, at $11.99 for a pair I figured why not. Can’t get enough clearance between the bar and the frame to put the new ones on, now. Worked it for 4 hours last evening. All the info I see on the web is to do the frame mount bushings and the links at the same time, but the links are less than two years old and are still good. Since you can purchase the frame mount bushings by themselves, I figure that the frame mount bushings can be changed by themselves. Do I have to remove the links in order to put the new ones on? Have I hosed things up by trying to put the new ones on without taking of the links?

Thanks, again.

The frame mount bushing for the stab bar should be able to be change without removing the links. Take both bushing clamps off and you should be able to pull the stab bar back away from the frame to slip off the bushings and put on new ones. It can be helpful to have an extra hand here to hold the bar while you do this.

Maybe it would be a good idea to check the ball joints as those can clunk when bad and can be very dangerous.

The bushings are in after much more work than anticipated. Had to get creative because space around the stabilizer bar was very tight. The verdict? The knock is still there “sort of.” It doesn’t appear in the morning or when the 'burb is cool. After driving a bit it comes in, but not as pronounced as before the bushings and not as consistently. I’m taking a few days break before diving back under to see what else I can find.

Continued input will be appreciated accordingly.

Since the noise started immediately after you installed the new shocks, go with the high probability things first. Something amiss with something you loosened/tightened, or one of the new shocks is defective. Here’s an experiment you could try: Try putting the old shocks back on, see if the noise goes away.