Transfer Case: Lockup Phases
I am making this entry to help share some information that I collected regarding our leaky transfer cases. I have just recently become a victim of the transfer case lock up. Luckily for me, it locked up going 5mph in a residential neighborhood. Others, unfortunately, have not been so lucky. I hope this entry will educate some of you about a few warning signs that I experienced, just before the lock up.
When the transfer case begins its leak, it doesn't stop until the transfer case runs out of fluid. My first initial sign, was a strange squeal that I could not track down. I checked the brakes, nothing was rubbing on anything. I checked the whole area. Nothing out of the ordinary. The squeal occurs only at times when you apply partial throttle. I did not hear a squeal when coasting in gear, when coasting out of gear, during braking, or full throttle acceleration. I did hear the squeal at approximately 10-60% throttle according to the S-AFC.
In this phase, you will begin to experience a slight vibration that you won't be able to track down. I initially thought this vibration came form my axle half-shaft, which had a split boot and no grease at the time.
Just before the lock up, there will be severe and violent vibration. You may also hear the squealing mentioned in the initial phase, but at a considerably higher volume paired with a grinding/crunching sound. At this point, the transfer case is about to lock up. Get the car of the road as soon as possible.
Hopefully this entry will help others gain some insight on the issues with our transfer cases. Don't ignore the warnings guys, or you could be badly injured. Best of luck to all of you. Be careful.