Ok so my garage called today about my hummer, they are replacing the front drive shaft and said while they had the drive shaft out there is a bushing right there that needs replaced, i asked him what its for and he didnt know, im starting to lose faith in this garage but I have to take it to them because its where the warranty work needs done, I hate asking such a broad question but anyone know what this bushing could be or what its called.

 

Precisely why I do all my own work on everything except Transmission and Differential internals. Time to stop in and have them show you the bushing thingy they do not know about.

The front drive shaft has a replaceable CV Joint at the Transfer Case end and U Joint and the front Differential end, never a need to replace the entire front drive shaft unless damaged as in bent. It may be simpler for a lazy shop to charge your for a new shaft and mark it up to make their money making job faster since it is not their truck.

The "bushing" may be the bushing that supports the front Differential at the cross support, they get dried out, crack, and slowly disintegrate. Possibly the center main bushing, but there are three total. Middle and a Left & Right outer Diff bushing. If one is trashed, gonna bet the other tow ain't so pretty either.

Here is some info, read the PDF instructions. H3 D.I.Y. FRONT DIFFERENTIAL BUSHING KIT

 

They didn't notice the bushing when they checked it out before? Makes you think, was the driveshaft causing the noise or the bushing? You can see the differential bushing in the video I posted for you:

 

Im kinda stuck with this garage because its under warranty and they are the garage that does the repairs, so at least they are footing the cost. Im just wondering if the issue wasn't the bushing in the first place, id hear a grinding metal sound when i gave it gas