Signs of a bad transfer case?

Schwag · December 18, 2003

Just had my truck at the shop for a vibration check. The guys showed me some black transfer case fluid and told me the clutches may be bad in it because of the black fluid and the case may need to be replaced. No shavings or material were in the oil though. I never heard any noises or had slipping just a vibration at 40 mph+. I'm thinking just flush & fill.

Are there any other indicators that I need a new case?

4x4 works great.

2000 GMC Z71 93,000 miles

Thanks.

JayMan · December 19, 2003

Uh-oh!

I'm guessing the AutoTrac had NEVER been serviced? I did my initial service at 600 miles, then once a year (Every fall) since.

The AutoTrac is really $$$, so please try the flush/fill before going to Plan B (Replace transfer case). Even if you have to flush/fill several times, that's still way cheaper!

Schwag · December 19, 2003

Jay,

If you've noticed I've been asking somewhat odd ?'s on here because I just bought this truck used knowing it would need some maintenance. The bottom was covered in mud, and it had a vibration up front at speed. On the lift we found the u-joints were dried out and the transfer case probably has not been serviced. I can assume that because I pulled the plugs and they were factory.

The truck runs and looks great, drives tight, and the 4wd is fine.

I just figure a little TLC and some tips from this site and getting it up to snuff will be worth it.

These are easily the best drivetrains out there.

I appreciate the advice.

JayMan · December 19, 2003

Yeah, that mud can REALLY work its way into things. You've also checked the CV joints? A bad/dry or damaged CV joint in the front will cause vibration, whether the truck is in 2WD or 4WD.

Sounds like you're also anal-compulsive about maintenance. WAY cheaper than a new truck, and even cheaper than a divorce!