I got this issue over the winter randomly driving home after work where id hit a pothole and there was a grinding noise and the car vibrated really bad. There was absolutely no power to the wheels even though i was still accelerating. Naturally i hit the break. The vibration stopped, I reaccelerated and everything was fine.

Ive tryed to identify the conditions when it happens and all i can gather is if i load the rear suspension very abruptly, like getting wheel hop or hit train tracks/ potholes (which obviously i avoid), it might happen might not. Ofcourse its one of those things you cant "make happen" when your trying to show someone.

Curious if anyone has had this issue? Any resolve? Its still very intermittent and can drive around confidently if Im careful. Needless to say, id like to fix it before i start damaging driveshaft splines, pr gears or what ever it is. Im confident doing my own work but dont have time/money to just poke and throw parts, its my daily driver.

Drive shaft / output splines look fine. No leaks at output shaft leading me to believe its deeper. Any help would be great. 2001 Blazer LT 4x4 w/auto 4wd.

I suppose i should mention this is after i put a rough country 2.5" suspension lift on it 6mo before. Any help would be great.

Thanks

 

Man that's a weird one, for sure. Maybe start by popping the rear diff over off and having a look-see

 

The vibration feels like its relatively right below when your driving. I was told the other day theres a retaininer (im envisioning a c clip?) in the tail piece? that stops the drive shaft from jumping from the "drive position" to the "neutral" position which is essentially what it feels like. I dont know if that makes any sense. Was trying to pick some brains here before i have a dissassembled drivetrain and scratching my head.

 

There's no clip that I know of on the driveshaft. The driveshaft will pull directly out of the rear of the tcase. It's splined, so there's no neutral position.

Now, there might be something weird going on in your tcase. I've completely rebuild mine before, but it's the np233, three button. I think the four button one like yours is way different

 

Yea, initially i pulled the driveshaft to check it out along with new u joints, just hoping maybe id get lucky but i figured if this retainer thing existed itd have to be deep or something.

Im gonna pull the tcase later in the week hopefully now that the cold and rain has stopped.

 

Good luck! It was a pain to drop mine. Thing is quite heavy! Just be careful, don't let it hit ya in the face!