Good morning guys, I need some help. I noticed a slight vibration along with a whining sound coming from drive train. Dealer replaced universal joint. Problem still exists. They replaced drive shaft with no change. You really notice the whining sound( like a bad bearing ) around 65 mph. I crawled under truck and u joint and driveshaft look good. I can spin the drive shaft that goes from the
Transfer case to the front axle. Is this normal ? 4 wheel drive works good.
I would appreciate any help, it's time to figure this out.