2001 Chevy Blazer 4WD Won’t Disengage

I have a 2001 Chevy blazer my 4 wheel drive wont disengage unless i put it in reverse and turn the wheel then back up. I’ve replaced the vacuum switch on the transfer case, replaced the in dash switch and just today put a new encoder motor on the transfer case. what happens is i try switching from 2hi to 4 hi and it does but it also then makes a whining noise like Pete Jackson gears.

     Mechanic JK:
When the truck is in 4hi or 4low, does it function and sound OK?

When its in 4hi it makes whinning sound like Pete Jackson gears but my rpm stays the same if i try switching back to 2 hi the indicator light says it is but turning sharp proves it still engaged, then i stop put in reverse crank the wheel back up a tad and its out.

     OK. Sounds like you have a problem in the transfer case or front diff. You need to get someone under the truck and listen for that noise to determine if it is in the transfer case or front diff. Or just drain the fluid from each and look / smell for being burned or gray from metal.

I think its in the transfer case some times it will disengage and clunk it feels like its in the transfer case also did change the transfer case fluid was fairly red didn’t smell burnt smelled like tranny fluid.

     Well, normally the fluid would get contaminated with metal, or look burned. If it just all of a sudden started happening, then you drained the fluid, it may not have had time to get contaminated.

It’s always been like that since i bought it 6 months ago only recently has it not disengaged. Just recently changed fluid after six months.

     Hmm. I would check the front diff. fluid. Also try what i said above to try to locate the sound. Best way is to have it up in the air on a lift, then finding the noise would be simple.

OK. Thank you.

2000 Chevrolet Blazer

My truck keeps loosing power and stalling out on hills.

Have any recent repairs or problems been happening on the vehicle?

No, we have replaced the spark plugs and wires.

And your problem only happens on hills?

Mainly when you step on the gas pedal in just dies and occasionally stalls.

Is the check engine light on?


I would recommend getting your Blazer scanned to find out what trouble code is stored. It will more than likely help with diagnosis of your stalling problem. Without is I would just be guessing. Most of the national parts store chains will do this for free.

I have a 2000 Chevy Blazer automatic V6 and currently it gets stuck in 3rd gear approx. 32 mph max it has not had a transmission flush in at least 1 year Will a flush and new filter do the trick?

You could try that and it may help, but you probably have a deeper concern inside the transmission.


I have a 1994 Chevrolet Blazer with the 4.3 ltr Vortec Motor. I am getting gas to schrader valve on motor but not to the spider fuel injector.

     Answer: The two plastic fuel lines between the hard metal lines and injector spider sometimes leak into the plenum which would limit fuel going to the spider. Also, on the side of the spider unit there is a regulator that can rupture and also leak fuel into the plenum which limits fuel to the injector poppets. If you can remove the upper plenum (intake) and have a look, you should be able to see if any leaks are present. Usually a portion of the lower intake will be all clean from where fuel has been spraying where it normally does not. If neither of those is your problem, do a fuel pressure check. You can have fuel at the valve but not have enough pressure to start the truck.

Live Chat Question:

My Chevrolet blazer broke down this morning. I heard a pop noise then the transmission it wouldn’t pull any more. It restarted it and it dragged but started still wont pull. The drive shaft appeared in-tacked.

     What year Blazer are you driving? Does the truck move at all in drive or reverse?

It is a 1994 Chevy Blazer. No it wont move in drive or reverse gear.

     Does the engine seem to rev up ok in park? Any noises when revving it up in drive or reverse?

Seems to be ok when the engine is revved up.

     Check the transmission fluid level. Add some if it is low.  Also smell it to see if it smells burned. See if there are bubbles on the dipstick. Do this with engine running in park. Let me know what you find.

Ok!! Thank you!! Will let ya know :)

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