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AWD problem (discouraged)

1425 Views 25 Replies 10 Participants Last post by  snobird60

I have had a problem with my 4wd for about 2 years. It started when I changed my encoder motor to a brand new one (dorman). My rear tires began to spin when I was turning (left or right). My mechanic told me that it showed that it was working now. and not before. There was something that wouldn't disengage and my differential was forcing. Last week, I changed the whole transfer case (TNT transfer case rebuilt), I had the rear differential oil changed (everything is fine, nothing broken inside), I had the discs changed , pads and caliper on the 4 wheels as well as the pedal break pads. I also changed the 2 CV joints. All brand new. Unfortunately, randomly, it may still have the same problem! Sometimes, it went back to doing the same thing. I turn left or right and he steers. I press on the accelerator pedal and I feel strain. The rear wheels spin. I do not know what to do. Most of the time, it works correctly, but with 4500$ spent, i want my problem to be fixed for good. Could it be a sensor abs problem? We read a code on the right front wheel yesterday.

thanks a lot.

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Do you know if you have Limited slip diff's Just checking all the boxes for configuration.. I have trutrac's in my van.

Also encoders are finicky I went through 3 dorman and others before I paid the extra to get an OE AC Delco PRO encoder.. My similar symptom has now gone away. Every so often when I let the fluids go too long, I do get a little bit of gentle binding.. An autotrak flush and figure8's usually cleans it up.
The bad encoder motor in one instance "locked" the transfer case. No errors but taking off in a straight line felt like someone had their foot on the brake for an instant before a short period of time then let go. Also shudder going around turns.

The second bad encoder was an error code and no AWD (put the vehicle up on a rack and front wheels did not "engage or spin at all"
Yeah. Just a low air in one tire can cause that symptom too.

Forgot that people are not aware of this.

If you want to be absolutely sure if the wheels are turning the same amount for travel the second article there gives you the most accurate way to tell and you don't have to put it up on a rack. You do need enough space to run straight and flat however.

I found that the amount of load you had can affect this. ie more weight in the right rear will "flatten" the tire ever so slightly, and affect the measurement. Not usually enough to cause too many problems, but I did find that the easiest check, especially if you are on the road (like I was in UT one time trying to figure it out before I came home) I used chalk on the out side of the wheels and drove the van in a straight line in a flat parking lot. figured out that one tire was low. I had a compressor in my van (always have one actually) so I adjusted the pressure on the tires and got them all to roll the same amount and problem went away.
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Removing the ATC fuse will cause an AWD error light on your dash because the encoder motor will not cycle when you start up the vehicle. Also I think the cruise stops working too?

But without the encoder engaging, you should never get that "binding" feeling. But you are also not going to get AWD to engage.
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