squirellman

Truck- 1997 4x4 5sp manual 4.6l

This is a followup to a previous posts months ago. It may seem wordy as this has gone on for quite some time now.

A few months ago at 50mph I heard and awful squealing sound. I hit the brakes and upon slowing to 30 I got a big THUD and jerk. The 4x4 light came on but I could tell by the lack of binding that I was in 2wd. I also could pull the shifter and engage 4wd and feel the difference. I got home ok and a few hours later the truck drove fine, the light was off and all was well. A few weeks later it did it again, 3 times in a few miles. I immediately took it to the shop. The truck didn't give any codes, and he couldn't repoduce the problem. In an effort to isolate the problem he disconnected the 4x4 switch. A few weeks went by and it happened again. I took it back and he was going to replace the GEM module after testing the shift motor and other parts. Upon removing the module he said it looked fine with no corrosion. He put it back in and drove it for a week. No problems.

Now... here we are 3 months later... and squeal thud 4x4 light. This has to be really hard on my transfer case to just halfway engage at high speeds.

Is this a GEM module malfunctioning?... any ideas. We are both a little stumped.

squirellman

No replies but ill update anyway. The mechanic has had difficulty isolating the problem. He went ahead and replaces the gem module. $300 part... I hope this is it. Anyone had this issue?

tan_1

I have had the exact same problem. Found a bad sensor on the front of the t case. Up and to the right of the front drive shaft was about a $60 part and about 10min to change, solved my problems. Hope this helps

squirellman

Hey tan1 I sure hope you are wrong! I just paid $300 for the new gem module. Drove 150 miles pulling the camper this weekend with no issues. Thanks for the info however... atleast ill have a better idea if it happens again.

squirellman

Meant to update this thread. 500 miles and no issues yet.