Squeaking while backing up?

Lately I've noticed a squeak coming from somewhere in the back of the truck whenever I have it in reverse. It sounds like its maybe coming from the rear wheels or somewhere under the bed. It sounds like a squeaky wheel to be honest but I know that doesn't make sense because it is not happening in drive. It is only in reverse at low speeds. It just got inspected Friday. I asked them to check it out and they shrugged it off but it passed. Anyone else have this issue and is this something I should be concerned about? Truck is a 2010 AC 4x4 sport with 80k miles.

 

Squeaking while moving slowly? Could very well be a bad U-joint.

 

Most likely u joint, probably the rear one at the back axle. I just replaced mine about a week ago.

 

Yep, I'd guess U-Joints. On mine the squeak was rhythmic with how fast I was backing up. So with mine being a Prerunner the original U-Joints didn't have zerk fittings so I replaced them with ones that did.

 

Thanks guys that was a quick answer. After doing a search on U joints it sounds like thats what I got. Its also been rumbling a little at low speeds between like 10-20 on acceleration which sounds like another sympton. Gonna call the mechanic and see about getting it replaced.

 

While it's parked with the shifter in neutral, you can crawl under and move the driveshaft. Try and rotate it a little back and forth at the u joints and you should be able to tell by either the squeak or how much play is in the u joint which one is bad.