Messed up repairjob????

[cerbomark]

Anyone have an opinion on this? I had the rear diff gasket replaced due to a small leak. After two days the half shaft seal on the diff and gasket were both leaking and brought back again.About a week after that I started to notice a vibration in the car at 40 mph only when the car was first cold.Then it would go away.Now I noticed the vibration at higher speeds and a howling sound at 90 mph only.Sounded like it was coming from the rear or maybe a tire. So I had the tires rebalanced and rototated. Nothing changed. I m wondering what could have been messed up on the first two repairs? My 1998 e430 currently sits back at the dealer. Any ideas so I can be ready when they call? Thanks

[Benzmac]

There are plenty of ways to cause a problem in the diff. If the service tech was not well trained, or was having a bad day, you may have to get a new diff to properly take care of this.

[cerbomark]

Just to let everyone know, We are sometimes hard on the dealers and they mostly deserve it, but in this case the problem seemed to be tire belts shifting on Dunlop sp5000. There was not a lot of wear on the tires but the inner 2 inches of the tire dropped 1/4 inch (Not wear). This was found by the dealer who advised me to replace tires. After the new tires were on I had none of the problems as listed above after the first 50 miles.