THANK YOU! Captain, I made sure to tell him that I would advise changing it and he said, It isn't broke why fix it.. And them I explained that something can break/wear out quicker and he scheduled an appointment at our local gm dealership. They quoted him $100 to go it.... Cheap?

Thanks for the transfercase help. Now I know what kind I got. And I didn't have to go out in the snow crawling under a muddy truck. THANKS

I will mark this up in the manual for maintenance.

 

This chart explains the NP/NVG numbering system: http://www.jameshalderman.com/images...p_chart_NV.pdf

Check your owners manual for service interval. If you don't have one, Google search it and download a pdf of the manual, it's free. Rule of thumb, no more than 50K miles. Manual & 3 button electric shift cases, (231 & 233) use DexronVI. Single speed Smart track/Auto track cases, (136 & 236) use Auto Track II fluid ONLY, there are NO substitutes:



Fluid change takes less than 30 minutes, no filters to fool with, and under $20 in fluid. No excuse for destroying a $1K transfer case