I bought my truck at 68K miles. When I test drove it, I pulled into a parking lot and tested 4-high and 4-low to insure they worked. When I switched back into 2-high, the lights on the dash went off like they are supposed to, but as I accelerated I noticed a squealing noise very similar to a brake squeal. The dealer assured me it was nothing to worry about, and I bought the truck.

All winter long, I used 4-high for snowy conditions, and never had the problem at all. I figured that using the 4x4 system again on a regular basis had loosened things up and whatever was squealing had stopped.

Recently, I drove through some mud and puddles of water, and it was a warmer day. When I switched back to 2-high, the squeal came back again. It was loud, and sounded terrible. This loud squealing seems to occur after I switch back into 2-high...and eventually it goes away.

I've heard other Ford truck owners complain about the same type of problem. It has something to do with how the Pulse-Vacuum Hublock system works on these trucks. My question is: does anyone know exactly what parts in the front end are making that squealing noise? If I knew WHY it was doing this, or which parts are responsible, I could fix it.

Any help would be very appreciated. Thanks guys.

 

Ok, I have read through lots of posts, and though I'm not positive yet I think my problem might be the outer seals that are supposed to keep dust and water out of the hubs. I think mine must be getting wet or dirty, and when I switch back to 2-wheel-drive they rub and squeal for some reason.

So new question... in late 2000 Ford switched 4x4 systems and started using a permanently connected front axle setup. So instead of having hubs, now they are setup like a front wheel drive car from what I understand. Will that setup have the same problems? I probably wouldn't have any trouble with them like I'm having now since they do not use hubs, right?

 

I would just convert to manual hubs. I have heard there is going to be some available for 1998-2000 pvh soon.
in 2001 they went to a live axle system, no hubs they are connected all the time. The differential turns all the time. The disconnect is at the T-case.

Oh and do you back up 10ft or whatever to disengage the pvh hubs?.

Rand

 

No, I thought the PVH system made it uneccessary to back up when going back to 2-wheel. I am only noticing the problem now when it's wet so I guess the seals have to be responsible. I've never had the hubs apart so I don't know what to expect when I get in there.

 

I have only seen them taken apart once or twice. The usual sign for replacement is when you take the hub off and can pour a lot of rusty water out.