No power to front wheels AWD

[Scottybones]

Looks like my AWD isn't working. My dad said to check for a loose wire or a bad solenoid, but after looking around the forum it could be a bad front drive shaft. Can anyone help me in the right direction to figure out what the problem might be?

 

[SoNic67]

First, do you have an AWD? Or a 4x4? They are different.
AWD is connected all the time to wheels, no switch on dashboard, no wires... It was installed only in V8 Explorers.
Look under and see if you HAVE a front driveshaft. Some AWD where castrated by previous owners by removing the front shaft instead of fixing it (or worse, hoping to "save some gas").

 

[Scottybones]

AWD. It's a V8 Eddie Bauer.

 

[albi1cnobi1]

If you truly have no power to the front wheels then you have a transfer case issue. A bad drive shaft would give you vibrations but would give you power to the front if it wasn't completely broken. Check to see if it(the drive shaft) hasn't been removed. If it is still there, then the problem is the transfer case.

 

[Scottybones]

This is a recent issue so I know the drive shaft is there. So the transfer case needs to be rebuilt I'm guessing?

 

[SoNic67]

How did you determined that you have no power to front?
Curious especially because you didn't even bother to look under the truck...

 

[Scottybones]

It rehantly snowed so I was looking for front wheel spin. I had limited sight. I had my wife look today and she said they were spinning. I thought there was an issue because I had a lot of trouble pulling the truck out and I've never had issues in the snow before.

 

[ZWilson07]

Dang beat me to it before I hit post.

So to be clear there isn't an issue any longer?

 

[SoNic67]

Looks like it was just too much snow for it

 

[ZWilson07]

Looks like it was just too much snow for it

Well also you have to remember with the AWD setup, it uses a viscous coupling to transfer more power to the front end so with wear and time, I am sure there are instances where certain people aren't getting a 50/50 split and could be only transferring the standard 35/65 that it normally uses or somewhere between there. Not to mention tires can play a huge role.

Another reason why so many switch to the 4406 transfer case. I am still up in the air on whether I am going to do the swap or not as mine is mainly a good DD setup that is pretty functional versus a ton of offroading.

I did enjoy my live axle setup on my 06 ranger and just with a flip of a switch, having a 50/50 4wd split. Although sometimes it is nice to not have to worry whether it is needed or not. Just hop in and go. Definitely pros and cons to both systems, and for what I do most of the year, a good functioning AWD setup works well.

 

[Scottybones]

I thought it was 65/35 split

 

[SoNic67]

It is 35/65 split on dry pavement. But that's not a fixed split like in a normal TC, the AWD has a true LS differential in the middle.
For example when one axle or wheel loses traction, the power gets redirected where it needs to be, and depending on the conditions, it can be as much as to 95-100% on one of the rear wheels. Or 95-100% on the front axle.

 

[ZWilson07]

It is 35/65 split on dry pavement. But that's not a fixed split like in a normal TC, the AWD has a true LS differential in the middle.
For example when one axle or wheel loses traction, the power gets redirected where it needs to be, and depending on the conditions, it can be as much as to 95-100% on one of the rear wheels. Or 95-100% on the front axle.

I was under the impression that the VC will never let the split be less than 35/65 and never more than 50/50. The huge amount of slippage in the system with one wheel getting 100% of power would probably fry the VC after awhile. At least that is what I have gathered.

 

[SoNic67]

That's what happens when you drive it without the front shaft installed. There is no "limiter" inside, it is just a classical differential with a silicon based gel in between (VC) - that gel solidifies the slipping axle with the non-moving one when heated (due to slippage).
In real world, you won't drive long distances with some wheels slipping constantly.

http://en.wikipedia.org/wiki/Viscous_coupling_unit

 

[ZWilson07]

That's what happens when you drive it without the front shaft installed. There is no "limiter" inside, it is just a classical differential with a silicon based gel in between (VC) - that gel solidifies the slipping axle with the non-moving one when heated (due to slippage).
In real world, you won't drive long distances with some wheels slipping constantly.

http://en.wikipedia.org/wiki/Viscous_coupling_unit

I guess this might make it even more important to go to a manual transfer case if you really are needing to 4x4 a lot.

 

[SoNic67]

Actually it works better that a 4x4 that locks the axles together. AWD it is there all the time, acts like a nice open differential when dry pavement, puts down 35/65 torque on axles (improving dry pavement stability) and it engages progressively the needed axle or wheel when needed (slippage), so for the driver is a smoother experience.

Any 4x4 in this generation is actually driven in 2WD 99% of the time. So it won't help you for example when you suddenly reach a road with some snow on right edge and dry pavement in middle. It doesn't help when accelerating in a curve (especially one that has some dirt/sand/water/cobbled stones).
In that situation, with AWD, instead of rear going "out" on acceleration, the whole vehicle "tracks" the desired direction. More of a safe feeling, for me.

 

[TheTech79]

Is there any manipulations i can try if i was to remove the front driveshaft and make the vehicle move on a 96 explorer 5.0 awd

 

[SoNic67]

Sure, but... Why would you do that?

 

[Scottybones]

So I lifted the front end today to swap out the fuel filter (which was a major pita and still isn't finished yet), and did some troubleshooting. When I turn the wheels by hand, the other wheel will turn with it. When looking at the driveshaft while turning the left hand wheel, the shaft will turn a quarter turn and stop, then will turn a little and stop again. Is this going to be a drive shaft problem or is there an issue inside the transfer case?

 

[SoNic67]

Probably driveshaft. Isn't very noisy while driving?