Noisy Manual Transfer Case

mcmlxv · July 12, 2006

The manual transfer case in my '04 K2500HD makes a constant gnashing sound while I'm driving, especially at highway speeds. The noise is only noticable in 2wd. 4wd is silent.

I didn't accept the service writer's first excuse when he told me "that most of them do the same thing. It's normal." So we took a brand new 2006 K2500HD for a drive to see if the noise was evident. Sure enough, it was, but not nearly as noticable. The dealer did end up replacing the linkage, but now the sound is actually worse.

1. Has anyone else experienced this gnashing noise?

2. If so, when does it occur?

3. What was the fix if any?

4. Does GM offer any improved lubricant over the factory fill that's in the transfer case now that might help?

It's a metal-to-metal noise. Not only is it annoying, but I'm concerned that there may be long term damage.

Thank you all.

JRKRACE · July 13, 2006

The manual transfer case in my '04 K2500HD makes a constant gnashing sound while I'm driving, especially at highway speeds. The noise is only noticable in 2wd. 4wd is silent.

I didn't accept the service writer's first excuse when he told me "that most of them do the same thing. It's normal." So we took a brand new 2006 K2500HD for a drive to see if the noise was evident. Sure enough, it was, but not nearly as noticable. The dealer did end up replacing the linkage, but now the sound is actually worse.

1. Has anyone else experienced this gnashing noise?

2. If so, when does it occur?

3. What was the fix if any?

4. Does GM offer any improved lubricant over the factory fill that's in the transfer case now that might help?

It's a metal-to-metal noise. Not only is it annoying, but I'm concerned that there may be long term damage.

I would keep an eye on the fluid level of the t-case. These cases have an annoying habit of the pump rubbing through the casing and leaking all the oil out. A small pinhole by the ribs where the rear d-shaft exits(IIRC)will leak all the fluid out while driving and fry the case.

Thank you all.

<{POST_SNAPBACK}>

I would check the fluid levels in the t-case and look for any evidence of leakng fluid. These cases have a habit of the pump wearing a hole through the side. Usually in the rib area by where the rear d-shaft comes in. It's a small hole, so look carefully.