Hello. Vehicle in question is a 2007 GMC Yukon XL 4x4 5.3
I recently did work on my truck and now there’s a terrible vibration (not to be confused with a shake) at about 72mph-77mph. Outside of that range, it drives fine.
The work I did… replaced u-joints. While drive shaft was out I replaced rear seal on transfer case. During the process of replacing seal, I noticed transfer case fluid was black so I drained and filled with new transfer case fluid. Replaced front right half shaft. This is all the work I did between the ‘before & after’ of the vibration.
Any feedback would great. Thanks for reading.