yesterday I bought a 1991 Ford E150 with Pathfinder 4x4 that I don't think is working

[ChadH]

I am as green at this as you can imagine. I bought a 1991 Ford E150 Econoline with the Pathfinder 4x4 yesterday. I can't tell a difference between the 4H or 2H being engaged. There is a rolling sound emanating from under the floor near where the transfer case is. It's not like the rolling sound in sync with the engine or driveshaft but something a little less harmonic and frequent. Any idea where I should begin. I bought the van as a good little project to work on but also should be a very useful vehicle for our family. I guess the 4x4 is as good as any place to get my hands dirty.

[kbeefy]

Does it have locking hubs?
Try spinning the front driveline in 2x and 4x. Watch the axle ujoints and report back.

[boywonder]

To further clarify....are you familiar with locking front hubs?

The noise you are hearing may be the front axles spinning when in 4x4 but the front hubs are not locked/engaged with the front wheels.

[ChadH]

Thanks kbeefy and boywonder. This does not have locking front hubs. I have a 1994 F250 4x4 with front locking hubs, but this pathfinder does not. 4x4 Automatic is labeled on the hub and there is no "notch" to turn to lock or unlock the hub. Please see the attached picture. (hopefully that comes through)

Do the non-locking hubs negate this advice? What should I do next?

[kbeefy]

I would still do the same thing, spin the driveline and observe the hub joints.
I one of those auto hubs sticks or fails, you won't have 4x.
I believe Warn makes a manual conversion hub if they wind up being an issue.

[ChadH]

Thanks a lot kbeefy. So I need to get this up on four jack stands and put it in drive in 2H and then in 4H and see how it spins or put the front two wheels on jack stands, put it in neutral and 2H and then in 4H and try and manually spin the front wheels?

[kbeefy]

Just crawl under and turn the front driveline by hand.

[boywonder]

....or jack up one front wheel and spin it.....in 4WD you should see the u-joint right behind the wheel spinning as well as front axle...or at least moving with the wheel.

[ChadH]

Okay, I jacked up the left front wheel just enough to get it off the driveway. The van was in 2H and the wheel spun freely with no movement from the u-joint. I put it in 4H, then neutral and 4L, all with the same results. This was with the transmission in Park. I assume it doesn't matter what the transmission is in since I'm not actually running it? Is this a pretty clean indication that the autolocking hubs are shot? Any other tests I should try?

This is going to be a really fun learning experience for me. Thanks a lot so far guys for the advice.

[boywonder]

It doesn't mean that they are shot......but it likely means something is not working properly.

..wouldn't hurt to check the other front wheel...same exercise...

Someone here with experience with Pathfinder conversions will likely chime in......sounds like the hub "auto lock" feature isn't working.

Can you post a picture of the front differential cover? We can determine what front axle you have.