Diagnosis help
 

Not all the time, but I am hearing a tinny rattle during acceleration from under my blazer. Sounds like a squeaky bed...hard to describe. Friend thinks bad U joint in the rear. I know it's not a lot of info but would a bad U joint make that metal-on-metal noise during acceleration? Quiets down when up to speed.

Re: Diagnosis help
 

Is it a rattle or a squeak? Yes, worn u-joints can squeak if it is lacking grease or if the needle bearings are damaged/missing. However it could be anything from a wheel bearing to a loose exhaust coupling to a body mount. You need to better pinpoint the location of the noise in order to narrow down the search. If I had a nickel for every squeak and rattle that came out of my Blazer i'd be a rich man.

Re: Diagnosis help
 

Yea I need to pinpoint it better, but it happens intermittenly...driving me nuts.

I'll grease it, if needed, and see if it affects it any.

Re: Diagnosis help
 

You might also check to see if you have anything hanging up periodically in the rear drums, such as a spring touching/rubbing.. or possibly the pads wearing near the wear indicator?? just a thought