My explorer rolls when on a hill

[BradR]

He has an AWD truck that someone replaced the radio bezel with one from a 6 cylinder Auto 4WD.

Yes, did you read the whole thread?

He also noted,

"yes. The plug that is going to the switch is connected to the wiring harness inside the dash "

 

[my pos mounty]

Yes, did you read the whole thread?

He also noted,

"yes. The plug that is going to the switch is connected to the wiring harness inside the dash "

And the last time you had the radio bezel off an All Wheel Drive truck was????
There are wiring harnesses that are not used behind the bezel of the AWD truck. And someone plugged one in. His VIN indicates that it was manufactured in St. Louis in September 1997, as an AWD vehicle. (posts #13 and 14)

 

[BradR]

To answer your question, last week, I installed a radio in one...

And, I was going by what he said. And unused plugs piss me off, especially ones that get power! lol. I've had to deal with a lot of stupid designs lately, but I won't rant here, lol.

 

[my pos mounty]

LOL Well, if you had one off, you know theres a couple of plugs back there that are not used for anything on the AWD truck. Plus you can probably see that if someone didn't pay too much attention when putting it back together, they may assume that one belongs plugged into a switch that does not belong on the truck in the first place.
The "rolling in park" is a very common problem with the AWD trucks once someone removes the front driveshaft.

 

[agon3279]

well thank you guys for all your help. I will get it repaired and give an update

 

[gijoecam]

I still think I am right. pizza 96 4wd still had a CAD front diff which will not fit with a v8

Someone might step up with an 96 AWD but as yet I have not seen one

If it's a V8 and has 4wd, it's AWD. The second-gen V8s were ALL AWD. There was no selectable transfer case offered in a second-gen V8.

The switch on the dash is likely for his air suspension. The 95 and 96 had a selector that provided increased ground clearance for off road operation. It wasn't common, but I've seen it from time to time on this forum.

The front driveshaft being out allows the viscous coupling in the transfer case to slip. Replacing the front shaft (and fixing whatever prompted it to be removed in teh first place) will stop the rolling in park.

 

[jseabolt]

Well, apparently someone has switched the radio bezel in your truck if you have a switch for the 4Wheel Drive. Your V8 is an All Wheel Drive truck and the transfercase is not controlled by that switch. It should not exist in your truck, thats why when you change the position of the switch, nothing happens. All V8 trucks were produced with either 2 wheel drive or All Wheel Drive.

The reason why your truck rolls when on an incline is directly related to the fact that you do not have the front driveshaft installed. The way that the transfercase is set up in an All Wheel Drive truck is different than that in the Auto-4 wheel drive truck.
IF you had the 4 wheel drive truck, that switch would control an electronic clutch in the tranfercase to engage the front driveshaft. The All Wheel Drive transfercase does not have that electronic clutch, but what it does have is a viscous coupler. This coupler sits between the input shaft from the transmission and the rear output shaft. Wrapped around the outside of that coupler is a chain, this chain drives the front output shaft. This viscous coupler will slip a little bit to allow the front and rear driveshafts to turn at slightly different speeds (such as when cornering). Now, if you have that picture in your mind, the transmissions parking pawl is holding 1/2 of the coupling at a stop (the input shaft only) but since the front driveshaft is not there, the weight of the vehicle will cause the coupling to slip, resulting in the truck rolling downhill. Until you replace the front driveshaft, set your emergency brake every time you exit the truck.
Believe it or not there is some good news, this shows that your viscous coupler is in good working order.

I'm still clueless about how the Explorer's AWD system works.

I know how a 4 wheel drive system works. One front wheel turns and one rear wheel turns once the transfer case is engaged into 4 wheel drive. But that's missleading. My father actually got a Jeep truck stuck because the front wheel that turns was off the ground.

So in a the Explorer's AWD system are all wheels actually turning at the same time? Or is one front wheel turning and one rear wheel turning at the same time (like a typical 4X4 system) and both axles have limited slip differentials?

When you say the viscous coupler allows the front wheels to turn slower than the rears makes me think that's the case.

Sounds to me like the Explorer's AWD system is fully mechanical. Is that correct?

How does it compare to the AWD system on my 2003 Subaru? I think that car uses a set of clutches to detect slippage.

 

[my pos mounty]

The switch on the dash is likely for his air suspension. The 95 and 96 had a selector that provided increased ground clearance for off road operation. It wasn't common, but I've seen it from time to time on this forum.

Yeah, but the OP mis-stated (LOL mis-remembered? is he Bill Clinton?) the year of his truck, but in post 13 we discovered it is actually a 98, so the switch is not for the air suspension.

So in a the Explorer's AWD system are all wheels actually turning at the same time? Or is one front wheel turning and one rear wheel turning at the same time (like a typical 4X4 system) and both axles have limited slip differentials?

Your first answer is, yes. Essentially the All Wheel Drive transfercase acts like the 4 wheel Drive transfercase with 4HI selected (well, sort of). The 4 Wheel Drive Transfercase does not have a provision in it to allow different rotational speeds between the front and rear output shafts, the AWD transfercase does.
Your second answer is No, it does not have limited slip in the front and rear differentials, only the rear has it.

Sounds to me like the Explorer's AWD system is fully mechanical. Is that correct?

Yes it is fully mechanical, there are no sensors, no computer control or any electronic controls at all. Full time power split 35/65 front to rear.