I HAVE A 2004 BUICK RENDEVOUS WHEN I HIT A BUMP IT FEELS LIKE THE REAR END IS ON ICE. WHAT COULD IT BE

Your diagrams are at the link below.
http://www.bbbind.com/free_tsb.html

check the u joints in the drive shaft or the rear end needs greased,or it could be going out.have you changed both the inner bearings as well on the front end?

We just went through this with our 2003 Rendevous. Clicking like crazy but wouldn't start. Replaced the starter but still doing the same thing. Our next step was going to be replace the battery (which tested well) and the ignition assembly. Out of frustration, I hit the top of the hood and the headlights came on!! Further investigaton proved that the problem was a corroded ground wire on the battery. Hope this helps

sounds like you need new shockers(must be done in pairs)when off, check all rubber bushes/linkages.

Most often the problem with front wheel drive models and this type of symptom ends up being a loose or broken motor/tranny mount. I'm sure there are a few shops around where you are at that might put it on a lift and check undernethe for free or a small fee. Also, if you have a floor jack and have the time you could check yourself, just look for anything that seems broken/cracked, and look at ALL the rubber componenets for wear and tear.

check your sruts

you better take it back so they cover it again and to verify the wheel and spindle are tight!!!

hand tighten and then turn 1/4 turn with wrench or until snug

I would check loose or worn rear suspension parts.

hi when you say hits a bump which wheel is it that hits the bump or is it the ront end hits a bump or rear and what did the fault codes say and what makes you think its not the sensors yates210456