I think my truck is stuck in 4wd

[Zman302]

I just bought a 1998 Ford Explorer Eddie Bauer with the 5.0 and I looked under it and noticed the front driveshaft is missing. I chocked the front wheels and lifted it up by the rear. I put the transmission in neutral, and spun the rear tires by hand. The front output shaft spins with it. I can even spin the front output shaft and it turns the rear tires. The 4wd switch has a “regular driving” and “off road” range and am not quite sure what that means.

 

[J_C]

You have (it had) AWD with a 5.0L, so it isn't stuck, there was no way to be in 2WD mode, except it must have failed so the prior owner pulled the front driveshaft to continue driving it as-is instead of repairing it.

 

[Zman302]

So fill me in here, so something in the transfer case is supposed to slip to allow for smooth turning when on dry pavement?

 

[Mbrooks420]

Yes. There will always be some drive to the front. The viscous coupling allows a difference of speed between axles. As this increases the fluid inside heats, and drives more power to the front.

The switch is for the air ride height adjustment, and has nothing to do with the AWD system. Be warned, the truck can creep a fair amount in park without the front shaft. If you park on an incline it very well might roll out of its space or into another car.

 

[Zman302]

this was with the engine off and me spinning it by hand with the transmission in neutral. It acted like it was locked 1:1 in 4wd. I checked the fluid and it’s black, but I don’t see any metal dust. Is this a sign that it’s time to rebuild the transfer case?

 

[Mbrooks420]

It’s hard to say. Prop shaft CVs are a high failure item. They aren’t cheap, and the remans are usually junk. I’d slap a front shaft on it, and try turning in a tight circle. That will tell you if it’s a t case or if it was just a bad shaft.

It should be 1:1 turning it by hand. There’s no way you could even come close to the forces needed to slip the coupling. It’s AWD, but always sends power to both axles.

 

[Zman302]

I think the route I want to go is to get a used one from the local salvage yard. What range of years and options have interchangeable front driveshafts for my vehicle?

 

[Mbrooks420]

Hard to say. 98 used 2 different lengths based on whether it was an early or late build. It’ll be 96-97 or 99-01, depending.

 

[410Fortune]

98-01 5.0L Explorer or Mountaineer front d shaft will fit, The V6 shaft will not work

 

[Mbrooks420]

98-01 5.0L Explorer or Mountaineer front d shaft will fit, The V6 shaft will not work

Not necessarily true. They changed the driveshaft length mid year. There’s no saying it’d be a 98-01 without knowing the build date.

 

[Turdle]

98 is in the "could be either" range.



There are 2 lengths of front drive shaft used during this time frame,

weld to weld measurement either 22 3/4" or 23 7/8"

You will most likely want one 22 3/4" long from a 98-01 awd v8 explorer or Mountaineer. Be sure to measure the length so you know what to look for if you grab the wrong one.

The driveshaft will need to compress on itself to fit into the front yoke, but you will definitely know if you have one which is too short or too long. I would think a pick and pull yard would let you exchange for the correct one if an error was made.

 

[410Fortune]

Interesting I have always had them in two stacks, v6 and v8, I never knew there were two diff v8 shafts.
What changed? the length of the tailhousing?

 

[Turdle]

Interesting I have always had them in two stacks, v6 and v8, I never knew there were two diff v8 shafts.
What changed? the length of the tailhousing?

I am not exactly sure when it happened, but I do remember Robert Pasquale ( torquemonster headers developer) mention at some point late 98 or 99 the engine was moved rearward 1/2" in the engine bay, and I bet this is the reason for the different length of front drive shaft with cv joint

Post 108 in this thread. Took me a while to find this


Torque Monster Headers Install Write-up and Review

All,

There was a change in engine position, not necessarily the firewall. When we were developing Torque Monster Headers, we used a '98 model for design and fitment. The first set we sold to someone with a '99-'01, the back tube on the driver side touched the firewall.

Back in the day when Ford was dealing with the vehicle flipping, (i.e. Firestone tires) they also made some slight changes to shift weight rearward. On the '99-'01 models, Ford shifted the engine/trans back a little over 1/2". Hence, the reason you later guys don't have as much room to remove the exhaust bolt from hell. Ford doesn't tell you this, but that was our findings in dealing with the later models.

The other side of the coin is, by moving the rear tube forward to fit the later models better, that same tube comes closer to the early models running the GT40 heads with the spark plugs pointing upward, but it is acceptable.

All the Best,

Bob Pasquale
Tech Performance & Engineering
Torque Monster Headers