Quote Originally Posted by vm4 View Post
Thanks!

I spoke with a local Chevy Parts dept. they said there eas a seal and a gasket that would be needed to be replaced, the guy told me I would need two quarts of Trak II...

It is push button( 2wd, 4hi, 4 lo). I understand thats the NP1 Designation... Any further thoughts?!

TIA


This requires Dexron III ATF. NOT Autotrac II fluid, unless it has the "Auto 4x4" button/option. Absent that feature, your is very likely an NP243/NV263, which requires Dex III.

"NP1" is the RPO code, indicating it is the NP243 (early/LD) or NV263* (late models/*XHD). All require Dexron III ATF. The RPO code for "Auto 4x4" is NP8.

Have a look at THIS WEBPAGE for pictures and descriptions of the buttons and TC's.

The NV246 TC is a COMPLETELY different animal, compared to any other common TC. It has load balancing clutches, that balances front/rear torque. "Auto 4x4" is a lot like the (older?) Jeep systems, and why they can be driven on dry pavement without all the scrubbing (although not recommended for extended periods). The NV246 was an option on 2500(LD), 1500HD, and lighter trucks. I don't recall it being offered on GMT-400 8600+ GVWR trucks.