Angry At AWD and Limited Slip

[dagsnregi]

Ok guys, here's the prob. I went to an OHV area w/a couple of buds and I got stuck twice. According to the window sticker, I have AWD and a 3.73 LS diff. First time I got stuck, three wheels were planted and one was airborne. That wheel spun like a madman, but no other wheel even tried to move. Next time was up a sandhill. I got stuck and the rear wheels spun and the fronts just remained planted.

From what I've learned from this incredible site is that there is supposed to be some kind of torque split between the front and rear diffs. Also, the limited slip rear is supposed to limit the amount of slip that any one wheel is supposed to have, granted allowing some, but I didn't think it would be that much.

Sorry for the long post, just confused as to what might have happened. Thanks for any help in advance.

Brian

 

[98EBV8]

Hmm..Just throwing out ideas....How about shifting to either 2 or 1 and pressing the gas slowly?

I got stuck backing up in my own driveway last spring with almost 30 inches of wet snow and all of my four wheels spun. But, eventually, I was able to get out after going forward a bit and back a few times. This is probably because with the tires and clearance.

Maybe get your transfer case fluid changed. Also, inspect the drive components to see they are working.

Shane

 

[dagsnregi]

how would I go about checking if all these are functioning properly? Any tips or tricks would be appreciated

 

[daniel cauchon]

Dag,
I have the exact same prob with my Ex it`s getting fixed right now as we speak ( guaranteed) so I let you know tomorow what`s the prob. and maybe the solution too.. but we had the exact same prob.

 

[MrShorty]

Can't help with the AWD transfer case not transferring power to the front, but, about the LS differential, two things come to mind.
From what I've heard, limited slips do prevent one wheel from spinning while the other wheel on that axle is stationary, except in the unfortunate case of one wheel airborne. For some reason, in this case, the limited slip breaks loose and lets one wheel spin by itself...don't really understand why.
Second, Ford's Trac-lok limited slip uses friction discs, which wear out; from what I've heard they last about 30K miles. When they are worn out, the differential acts like an open differential. They aren't overly difficult to replace; I've got a thread on it if you're interested in doing it yourself.

 

[TPLYNCH]

Did you buy it used? You sure the window sticker was accurate. Check up front an make sure you have the driveshafts going to the front wheels......

 

[Jason_25]

I think that's normal for the AWD system. It doesn't "lock" the axles together. If one axle begins to lose traction it gets all the power.

 

[Fusion213]

I was thinking about this situation a long time ago where if you have one front wheel airborne, wouldn't the AWD t-case transfer 95% power to the front, and since it's open in the front, that one wheel would get all the torque and just spin like crazy?

 

[Robert]

That would only happen if you had an open axle in the rear and got a rear tire and a fron tire airborn (not very likely unless you have very good balance). In this situation, the rear airborn tire would start spinning which would transfer power to the front which would direct all of the torque to the front airborn tire. As long as you have either both front tires or both rear tires on the ground one of your driving wheels should get some power. Of course if the tires on the ground are on a slippery surface all they would do is spin. That is a downside to having AWD and not a transfercase that will actually lock the split 50/50 regardless of surface or conditions.

 

[dogfriend]

its really not that difficult

Originally posted by Robert
That would only happen if you had an open axle in the rear and got a rear tire and a fron tire airborn (not very likely unless you have very good balance).

I did this about 1 week after first buying the Explorer

Tryed to do a three point turn on a relatively steep hillside and didn't see the wash out gully until the left rear wheel went in. The front right came up and voila! - no wheel drive

My girlfriend really freaked out.

 

[Big Bear Bob]

As far as the rear end I've heard if you apply a little pressure to the emergency brake it will cause both rear wheels to spin. Sort of like fooling the system into thinking you have rear traction on both wheels.

I got mysrlf hung up once and gave it a try, and it seems to work, I'm pretty much a newbie, but the guy who told me about this trick has been off roading for years, so I would give it a try next time it might work with AWD.

I have a 373 ls in the rear and open diff up front. I do think I have an advantage off road because of 4low, but you would think AWD ment AWD.

Good luck and hope this info might help in the future.

 

[Robert]

3B - that worked because you have a limited slip. The limited slip by default (when it's working properly) will limit the torque difference to about 40 ft/lbs between the two wheels. When one tire is airborn or on ice it will only take 5-10 ft/lbs of torqe to get it to spin. The other tire will then only get 45-50 ft/lbs of torque. Sometimes this isn't enough to move your vehicle. When you applied your brake, you forced more torque to go to the loose tire which in turn allowed more torque to go to the other tire. It doesn't work nearly as well on an open differential though since the only way both tires will get torque is if they have an even resistance placed on them. Usually to do that with the brakes, your engine will bog way down as it tries to overcome the brakes.

 

[dagsnregi]

just wanted to say thanks for all the information. I knew that this site was cornucopia of knowledge. Thanks again.

Brian