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Kick Ass Matt
09-17-2007, 19:08
Something is wonky w/my 4WD. I dropped it off at a local tranny place along with this note. See if it make sense to anyone of you and please comment if you know what might be wrong with it.

Mike I need your help this time with my truck. This time is a rush one because I need it by Friday night; I got a job up at an open pit mine this coming weekend for work. It’s in the middle of no where. We’ll talk over the phone about this one.

Here’s what I did to pre-checked it out.

All 4 wheels off the ground I had the truck in 2WD, drive/reverse. Only the back wheels turn. 4-HI only 3 wheels turn (RR, LR, LF). But I was able to stop one front side (LF) w/my hand. To my understanding the front is a locking diff which means LF and RF should turn at the same time/speed when 4HI is engaged; which is why they ask you to only use on snow/wet pavement. Correct me if I am wrong.

I left the thing in 4HI drive and turned the truck off in drive. Turned the key to key on engine off position. 4HI light on the T-case is still lit. I crawled under and turned the O/P shaft on the T-case by hand and only one front corner turns the other doesn’t.

Here’s where it gets interesting. I put the thing in 4LO and drive only the back wheels turn. Reverse was the same. Then I did the same thing as I did above. Neutral key on engine off turn drive shaft by hand and nothing happens in the front. Turning the front I was also not able to get the drive shaft to turn.

Also the t-case leaver VS t-case function is out of whack sort of like what happened to my tranny when I first brought it in. Adjust or better yet replace the linkage if you have to. Also can you put in a new 4WD actuator? The early funky GM thermo activated ones are known to crap out.

Other than that I have nothing more to say but the fact that you did a good job on the tranny. At lease it doesn’t leak like a sift anymore ****ing up the driveway.

Truck in question is a 94 K2500 6.5 Diesel Sub with 14-bolt rear; 4.10 rear.

JohnC
09-18-2007, 10:08
Unless someone changed it, the front axle has an open differential. 4WD is really at best 3WD...

93GMCSierra
09-18-2007, 10:24
And in most cases the rear diff is also open so most times your looking at one rear an one front spinning.