Hey everyone-

I have few quick questions regarding what type of transfer case I have. I been doing alot of research regarding transfer cases lately because the front drive shaft pinion seal coming out of the transfer case is leaking a little. While researching fellow members are all referring to the transfer case types as NV236, NV233, NV231. I believe I have a NV233 because I have the 3-button electronic 4x4 controls (2wd, 4wd HI, 4wd LO). Am I correct in my assumption? This would really help narrow down the threads I'm reading through.

I'm also trying to track down info about my transfer case, because I want to add a little fluid if I need to since its been leaking a little at the seal, unitl I can get the seal itself changed. I looked at the owners manual and they have two classifications of transfer cases.

1.) Electronic transfer case - which the suggest "Dexron-III Automatic Transmission Fluid"
2.) Automatic Transfer case - which they suggest "Auto-track II Fluid"

Question?: Which transfer fluid is right for me, I believe its the 1st one (Dexron-III Automatic Transmission Fluid) since I do not have the 4 button 4wd auto selection. Is that correct?

Blazer Info:
2003 Chevy Blazer ZR2 - roughly 111,000 miles
3 Button 4wd selection (2wd, 4wd HI, 4wd LO)

Any help, info, links would be appreciated. I looked in the DIY stickies but couldn't find anything that related to me. Thanks.

 

nv233 is correct

autotrac is for auto 4wd transfer cases(4 button switch) - nv236

dexron 3 would be nv-233

the nv231 is the manual shift


so yes you are correct

If changing I would recommend dexron VI

 

Thanks for clearing that up for me.
Whats the benefit from using "Dexron VI" rather than the "Dexron III" recommended by the owners manual? I usually don't stray from the fluids that the owners manual recommends unless there is benefit from using something better. I don't do any off roading, or drive in harsh conditions that require 4wd that often, just occasional Ohio snow falls.

 

Dexron VI is a synthetic ATF. It is backwards compatible with all Dexron III applications.

 

So the Auto-Trac NV236 requires a special fluid only from the dealer? I was going to have a seal replaced on my transfer case on Thursday and the place said that it takes Dexron III or however its spelled. I thought it was something special. Is there a difference?
Thanks

 

They are most definitely different. Do NOT use dexron in your NV236 transfer case. GM Autotrak 2 fluid only.

 

It's a good thing I found this then! I thought I heard somewhere it needed a special kind, so i called the dealer and sure enough that's what they said after a few tries on the computer (it may be 11 years old, but they should have more than what they do on it). Does the NV236 have more clutches in it to be able to lock and unlock on itself when it detects slippage, is that part of the difference or something? Just curious, I like this setup it comes in handy

 

The NV236 has a clutch on the front output that allows for variable lockup of the front output shaft. The Auto4wd option engages the front axle up front, then sends power to the front axle as required at the transfer case. When you select 4HI, the clutch locks up completely and you get a 50/50 power split front/rear.