Offroad Trailblazers and Envoys

4WD high binding problems

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by Berettaspeed » Fri Feb 05, 2016 9:47 pm

I have been noticing odd binding problems in 2WD. Sometimes when doing a Y-turn or U-turn I get a binding like its in 4WD, and its random as far as time of day and driving time. Has happened maybe 3 or 4 times in about a month. When I straighten out the wheels and drive it goes away. I changed out my leaking axle seals about a month ago when I bought it. I drove it in 4WD for a week or so when we had snow and it seemed to work just fine. I noticed during that time I was only getting about 10mpg. I was shocked at low mpg. After snow was not that bad I put it back in 2wd and noticed about 12mpg-14mpg depending on driving habit.
I was experimenting tonight with my turning in a parking lot and on the street with 4wd since I just installed my 2.5" lift. I wanted to make sure everything turned good in 2wd and 4wd. Going Straight is not all that bad, but once I turn a corner left or right even going straight again the truck slows down like there is binding. I can turn the wheel left to the 3 o-clock position and right to the 9 o-clock position before binding starts to happen. Even going straight after coming out of a turn, the binding is still present. Truck will slow like brakes are applied lightly. Coasting wont happen very long, and in Neutral it will slow and wont roll down a slight incline. I didnt want to stress anything out so I put in neutral and back into 2WD. In 4wd before a corner it will roll and coast just fine. I can drive straight and turn slightly no problems.

Vehicle has almost 200k on it and the fluid didnt look good when I changed it. Metallic and low. I cleaned it out and plan on doing another fluid exchange. I guess Im wondering how everyone elses truck acts on dry pavement. Other peoples vehicles seem to get pissed in 4wd, but once they go straight or ease up on the wheels its gets tons better. Which makes sense. Mine however just stays pissed off.

Any hits on dying front diff or center diff issues?
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by Berettaspeed » Fri Feb 05, 2016 10:13 pm

This is my First 4wd vehicle so I guess not sure of what to expect as a daily. I guess i never put a truck in 4wd on dry pavement. Seems like this is totally normal. ( searched after posting )(viewtopic.php?f=11&t=2310)

If the case Im super happy. The only fear is the 2wd binding..... that is not right at all. Imo. I also read another topic on bearing failure causing excessive binding?


So Im still a bit concerned I guess.
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by hilljb » Thu Feb 11, 2016 3:05 am

That's potentially an interesting problem, but probably just usual transfer case bind-up.

Sure, you should never engage 4WD on dry pavement. The A4WD is nice for that, since it will disengage sooner when not needed. 4WD on dry pavement/rock/etc will not only bind the front and rear axles together and cause the braking sensation you mentioned, but it will eat your CV axles and they'll start to bounce under torque after enough of this. Especially in a lifted vehicle, this becomes an issue. A lot of times, it is unavoidable... driving on steep slick rock, etc.

For assurance, I'd find a dry dirt lot and slowly drive in tight circles in 2WD. If you get bind-up then, report back asap. I mean, you could have a fused differential ... but that's not likely. You're probably fine.
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by Jrgunn5150 » Thu Feb 11, 2016 3:55 am

G80's have been known to not disengage properly from time to time.
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by bartonmd » Thu Feb 11, 2016 9:57 am

Jason (Hilljb), he's talking about a bind that feels like 4WD, but he's in 2WD.

Michael, one of two things is happening. Either the tcase is stuck in 4WD (bent shift fork, TCCM problem, or something), or you've got a G80 that's not properly unlocking. If you've just engaged the G80 pretty hard, it'll sometimes stay locked for a bit, but should unlock if you coast or reverse.

As a troubleshooting thing, you could find out which it is by turning circles in a parking lot or something, with you or somebody else outside the vehicle, and seeing which tire scrubs. If it's the inside front, it's in 4WD, and if it's the inside rear, it's likely in 2WD and you have a G80 that's not unlocking.

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by HARDTRAILZ » Thu Feb 11, 2016 3:48 pm

I agree with above. Also--Have you checked your wheel bearings? Had an alignment since you lifted? Checked the brakes for any sticking? Just extra thoughts that may help if turning circles does not reveal a culprit.
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by Berettaspeed » Tue Jul 05, 2016 6:20 pm

Sorry for not getting back. I do have the G80 code and I changed all my fluids in the drive train. That seemed to fix the problems. Granted, when the 2wd binding was going on, it was usually early in the AM when really Cold during winter. No problems really since new fluid.

I cant imagine fluid assisting that much, but the AWD selection improved once the front diff was freshened up. Leaky seals all over the place on the front.


I would go in reverse as well to clear up the problem. It was also during 3 point turns if i forgot to mention. I would go straight in reverse and throw in neutral to coast. I think the rear was not unlocking like a few mentioned?
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