What could cause a noticeable noise and vibration from the rear axel of a 1999 Chevy Tahoe 4x4 W5 7 automatic transmission at 74 mph?

Answer 1

If the noise or vibration is coming from the rear axle itself, then you may have a worn set of gears in the rearend that may need replaced or adjusted. The vibration may also come from the driveshaft in need of some new universal joints. I always start with the cheapest fix and would pull the driveshaft, take it to a driveshaft repair shop and have them check balance and while it was there replace the universal joints. Reinstall the driveshaft and see if the problem is still there. If it is, then it is time to get into the rear end and pull the rear cover off and maybe determine if there is a lot of gear play, metal shavings or broken parts. It takes an experienced person to replace rear gears. Doing it wrong and getting the gear set meshed incorrectly can lead to premature failure. The average Joe can do it but plan on buying, borrowing or renting certain things to make sure you do the job correct, otherwise you will be doing it all over again. Some jobs are better left to the pros.