rear noise help

[STL_Denali]

Recently been hearing a noise from the rear end during low speed turns both right and left, and even when backing out of the driveway. Not really loud but a noticeable “clunk clunk” to almost “creeeeek”. The kicker is that it only seems to do it after I’ve been driving it a bit, won’t do it cold.

Just trying to get some knowledge on what it could be or any past experiences with this. Thanks!

05 Yukon Denali

 

[ScottL4619]

Have you checked/changed your rear differential fluid lately?

 

[STL_Denali]

Actually just had the shop do it (about 2 months ago) as part of the 100K maintenance. Could they have messed somthing up?

 

[ScottL4619]

It's always possible...I don't trust anyone to do my routine maintenance because I've heard too many stories of the young and/or inexperienced workers just missing things.

Checking differential fluids is very simple and doesn't necessarily require lifting the truck (especially if you don't have a large belly). Remove the top bolt and the level inside should be just below the hole. This goes for front and rear differentials. You can use a coat hanger with a bend if you can't get your pinky in there. If you need to add some, auto parts stores sell containers with cone tops for easy adding of fluid.

 

[STL_Denali]

So your saying the low diff fluid could be causing this noise? Huh.. This is the first truck ive owned so im a newb at some of this stuff.

I will check it out.

 

[ScottL4619]

It may or may not be causing the noise...or the fluid could have been low for 20k miles and the damage is already done. It could also be your emergency brake kits. However, for 5 minutes and no cost, I would most definitely check all fluid levels first.

It could also even be your front HUB assemblies and the noise is just traveling through the chassis and sounds like it's coming from the rear.

 

[afpj]

Had similar issue last year. Thought it was a bearing as it only happened when turning one way, but finally had an assistant to listen and it boiled down to rear diff. Had the fluid replaced (was replaced 30k miles previously) but new shop thinks that the previous shop did NOT put in the special lubricant needed for my rear locker. That did the trick and has been good for 30+k miles since.