I've got a 2000 4.3 Blazer, and had ro rebuild a ailing 4L60e transmission. When re-installed, I discovered the transfer case had shifted itself into neutral, and allowed no movement forwards or backwards. Removed the encoder motor (236 or NW8) and discovered a 15 mm wrench could shift the transfer case in a couple different directions...turned counterclockwise, it made a hard shift and stayed in position. Turned clockwise, it bounces against a spring of some sort...can any one tell me what the correct position that shaft should be turned to stay in 2wd?

I don't care if the 4wd ever works. All I need is 2wd...My dad's Jeep club cured me of any offroading. I don't even like gravel driveways.

Thanks in advance for any info.

Jim

 

I believe if you turn the shaft counter clockwise all the way, you will be in 2wd. One click back would neutral, two would be 4hi, three would be 4lo. Pretty sure this is how it ***. I have a 99 1/2 ton with the manual transfer case, and a 72 K20, that both operate this way. The 99 has the same transfer case, but not the 72. Pretty sure this is the way all GM transfer cases are set up.

Give it a try by going counter clockwise, the give it a test drive. You'll know pretty quick if your in 2wd or 4lo.

 

The NV236 transfer case will transition from 2HI to 4HI through a viscous coupling that can vary the torque output to the front axle. The spring that you are feeling is the actuation of this viscous coupling. 2HI would be the location directly before the spring feeling and 4HI would occur if the shift fork were turned against that springy feeling. I cannot recall ever trying it when I have had the opportunity, so I'm not sure if there are actually detent positions in the NV236 transfer case for 2HI or 4LO. I'm certain that there is no detent position for 4HI and I do not think there is one for neutral (between 2HI & 4LO). The encoder motor on the NV236 transfer case has a brake assembly fitted to the back side of the dc motor that powers the unit. This brake allows the encoder to be locked into any position it desires without the aid of a detent in the transfer case. This is important for the operation of the Auto-4wd mode as it will lock in on a position that engages the front output viscous coupling consistent with the slip the TCCM has detected.

Long winded, but I guess my point is that if you cannot feel definitive positions, you'll have to do your best to get the shaft held in the position where it is just starting to get into the spring return zone. This should be 2HI. You would need to fabricate some kind of bracket that would hold the shift fork in this position.