Posted by Mike on December 01, 00 at 13:29:38:
In Reply to: Strange rear end noise (long) posted by Mike P on December 01, 00 at 11:12:39:
: I've got a '96, 3/4 ton, 454, 2wd Suburban with a very strange noise coming from the back end. It's not a differential sound. It sounds like the classic cartoon spring-bounce sound, you know "sproing". Like when the Coyote bounces on his Acme springinator as the Roadrunner runs right by.
: It generally only happens with body roll. When the right front tire rolls into a dip (at slow speed) the "sproing" happens. And when the left rear rolls into a dip (at slow speed) the "sproing" happens. Right turns, with normal pavement uneven-ness, make it do it, also. It sounds like something could be moving to the left under there and banging into something else, but I can't figure out what's back there to make the noise.
: I've checked the exhaust to see if it's banging ito anything and can find no evedence of contact and can't duplicate it by shaking the exhaust around from under the truck. There's no obvious visible evidence of metal on metal contact on the spring mounts or shackles. The parking brake cables aren't tight enough back there to make the noise when I shake them around.
: I have not had the truck on a lift and yanked the axle around to try to make the noise. I'll try that this weekend, but I wonder if I can move the axle against the springs and shocks more than a fraction of an inch.
: Stock 2wd 3/4 tons don't have a rear anti roll bar, but I did just add a Hotchkis front and rear sway bar kit. BUT, it made the noise before I touched it!!! And still does.
: This is NOT the driveline clunk from the transmission/driveshaft splines. My '88 2wd does that, and this is a completely different sound.
: Has anyone every had the Coyote under the back of their Burb?
: Mike P.
Check your shocks. If any evidence of leaking, they are dead. If not, grab the shock as best you can with your hand and try to wiggle it out of the truck. Use some force. If it feels at all loose, it's dead. You cannot test the shocks by jumping up and down on the bumper. The springs are way to stiff to allow it.