I have a Sierra C3, once the TC is up to operating temperature it will do the infamous crow hop when turning really tight and slow. gets embarrassing pulling into a parking spot...and I'm done with having it hop.

Anyways, theres the same thread on every forum which has the same exact reply from GM Document ID # 873908 on how to test the viscous coupling using a tester. Is it just this adapter I found on ebay?

Transfer Case Torque Check Adapter Kent Moore J-45382 GMT610 FREE SHIPPING

Has anyone actually done this test and found the VC bad and replaced it? If so, where do you get a replacement? Or did you just pull another nvg149 from a junkyard? Upgrade to a newer transfer case?

 

Save the money on the tool we have a dealer and never wasted our time using it. If it's acting the way you are describing and you plan on keeping the truck I would just order a new tcase from gm for it and call it a day. It's a 2 hour swap and the trucks back on the road with a warrantied tcase. It' will have a 3 year 100K mile warranty if my memory serves me correctly.

 

Are you able to buy the components to it and just rebuild it? I found a rebuild kit that had the bearings and gaskets but I wasn't able to really find much more than that. I'd just rather weigh out all the options before putting a new tcase in.

 

It can be rebuilt BUT if you can't handle the job yourself by the time you pay a shop to rebuild it you are close to or over the cost of a new gm case and don't have the warranty that gm puts on theirs.

 

What About A Jasper?

 

They are pretty straight forward to take apart.

 

so your saying you have some experience with them... haha

I'm just really not sure which way to go, looking at the parts diagram over on denalitrucks it looks pretty simple but I use this as my daily driver so I don't want to not have all the parts on hand when I would tear into it as opposed to just buying a reman with a warranty for twice the cost probably. I need to price it all out I guess next. Has anyone tested the viscous coupling the way its shown in the gm service bulletin?

 

Had to take mine apart to change the input shaft for my 80e trans.

 

A new viscous coupler is around $800.

They can be remanufactured though. A Local to me transmission/ differential shop has them for around $300 with exchange last time I checked.

 

well I called all the local tranny shops to me and a few were really knowledgeable on this transfer case and they were all pointing to the viscous coupling also. Waiting to start getting phone calls back today with prices