I wasnt sure were to put this post nor what to search for. While driving on the highway for a while the front right shaft tries to engage. I slow down to 50 and put it in 4 hi then switch back to 2 and its fixed for a couple hundred more miles. I had it looked at and the teeth were all gone so I had it replaced and was told that the problem was fixed. After a couple days of driving then it started up again. Any ideas?

 

I ve been having a similar problem. Right side wont disengage after using 4wd. Just grinds until it finally disengages.
How much did it cost you for the repair? (parts) I believe something is stripped on mine.
Sorry i couldnt give you any advice at this time. Im still working on the problem and will report back with any info i find out.

 

It's possible that the transfer case switch (top right side of the transfer case) is not venting and you still have some vacuum to the actuator (under the battery) and holding some pressure on the cable that goes to the front axle actuator lever.
For $30.00 you could change the switch.....just a thought..

 

Thanks for the reply Chevy Lover.
I did take the vacuum line off at the canister to see if that would release the actuator if it would have possibly been the vacuum not venting ,but it didnt help.The more i think about it.....that probably wouldnt have released the vacuum at the actuator anyways. I'll check into that further over the weekend.
Besides that problem......when i put it in 4wd (in the snow) the front right side wheel sounds like its skipping gears when i go forward or backwards.. (no forward motion of the front wheels at all unless all 4 wheels are jacked up off the ground) I cant tell if its not engageing all the way or if the gears are torn out of the differential. Do you have any thoughts on this?
By the way.......Mine is a 1996 Blazer . 4 door , 4.3 vortex , 126000 miles

volrath169, Sorry for highjacking your thread. I hope you find the answers you need as well.

 

I could have sworn that I read in my owners manual never to engage the 4WD over 30 miles per hour. I had a 1988 Blazer that made the same noise every once in a while and if I slowed down it would pop out of that grinding noise just before I came to a stop. It was very annoying and I was not even using 4WD when it would engage itself. I sold the truck before I ever found out what the noise was. I am curious to see what the eventual outcome of this thread is. What that damn noise was.

You know what sounded very similar was that growling noise my ABSuse to makebefore I cut the wires to both front brakes. Solved that aggrevating noise quickly.

 

This info is taken from the 2003 Blazer owners manual .Shifting from 2HI to 4HI
Press and release the 4HI button. This can be done at any speed, and the front axle will lock automatically

 

My uncle who has an S10 pickup said that his 4wd sometimes will not engage when its cold out. (cold weather = 4wd) if you ask me. Anyways....when i was having trouble it was infact cold outside. I tried it again in the mud yesterday when it was about 50 degrees and everything worked correctly. 4wd engaged and disengaged properly. Apparently when its cold it doesnt engage the differential all the way and just grinds.I say the differential because the driveshaft from the transfercase is turning when the grinding/stripping is takeing place.

Growling and pop:
My brother has a 92 full size chevy pickup and he said that his has always did the growling after disengageing and would quietly finish fully disengageing after a short time until he put new tires on the back (only) which were the same size but differant manufacturer, and now he will get that "pop" when it releases.This is understandable because im sure all makes of tires are slightly taller or whatever and its causeing it to bind. I have the same configuration with my tires so im pretty sure thats why i will sometimes get the pop as well. I can handle the pop so long as it comes out.I know its not the best thing in the world to run 4wd with tires that are not all exactly the same but if you use 4wd only when absolutely needed and on snow only, it shouldnt hurt it too much.
I believe the growling noise is the differential being turned (pushed) by the front wheels until it releases.

I havent had this Blazer long enough to find out if will self engage while going down the road. I would bet that its only the differential engageing and not 4wd.The only thing i can think of that might make that happen is vacuum is somehow bypassing and engageing the differential.

Now...on to the next question. What component is effected by the cold? Anyone have any idea?

 

Mostly my left knee, but sometimes my right as well.............lol

My guess would be the transfer case vacuum switch, but that's only a guess.

 

"This info is taken from the 2003 Blazer owners manual .Shifting from 2HI to 4HI
Press and release the 4HI button. This can be done at any speed, and the front axle will lock automatically"

You are correct MR Lover.

I just re-read and it is from 2Hi or 4Hi to 4LOW that the vehicle needs to be going less than3 MPH or stopped. My error. But I have never tried 4Hi on the fly anyway. I always stop and then actuate the 4WD.

 

It cost me$650 for parts and labor.