Hello, i have a question on my 2000 blazer 4x4, it has the 236gm transfer case with the dash switch having 2H,4H,N,4L,AUTO on it.My question is in 2H should the front driveshaft still have full power going to it from the transfer case and still be turning?or should it turn freely?.I have read several different answers online and have a couple GM dealers and transmission shops and i get both yes and no anwers?.The other thing that makes me wonder this is in my owners manual it states that in 4x4 auto mode the front axle will be locked in but the transfer case will supply power to the front driveshaft if it detects rear wheel spin.If this is the case then i assume in 2H the driveshaft will not be spinning?.Any help would be appreciated,Thanks

 

Me thinks that to be a New Venture transfer case with Dash mount push button electronic shift (encoder motor) . Is that an auto-trak system ? I believe 2hi should divert most torque to the rear - but You have a viscous coupler clutch system inside that transfer case so the front output shaft is never fully free-spooling . Just the front differential is not engaged in 2hi .

 

Wait how do you know the front is getting power? If its in 2WD then the front tires should not have any power going to them. If you drive into something slippery and your front tires spin while youre in 2WD thats not right.

 

Well this is my first 2nd gen blazer, i bought it with a bad engine,i just done the engine swap and started working the gremlins out, as ive been driving it it seemed to be in 4x4 although the dash switch indicated it was in 2H, i put it up on the lift and sure enough it was locked in 4H, upon troubleshooting the system i discovered the front axle actuator cable was frozen,i replaced that and the front axle disengaged, but with it up on the lift in drive and running, the front driveshaft is still spinning with full power when i have it 2H.As far as this being auto-trac im not sure, i dont know enough about these,it does have the 4 button dash switch and a 236GM transfer case.I do know the vaccum switch on the firewall under the hood is bad and currently leaves the front axle disengaged,i have not had any luck finding one yet but i dont think that has anything to do with the tranfer case not going into 2H, that just controls the front axle.

 

As onebadsuv eluded to, the NV236 transfer case (which is what you have btw) has a preloaded clutch which will always apply some torque to the front driveshaft, even when the transfer case is in 2HI. There is nothing wrong, that is how it works.

 

Ok sounds good, thanks for the info.