Hello all. I apologize on the front end for the length of this post. The wealth of info here is a little overwhelming. I had recently purchased an 01 250 Super duty 4x4 gas burner, 99,000 miles. On our first trip with a very light truck camper (camper and weight - 1,500 lbs.) we encountered problems. When I first got the truck and looked in the manual, it seemed to me to say to turn both hubs to the right for the auto setting (the stickers on the hubs are missing). When I checked them, one was turned one way and one the other. When we had a snow and very cold tenps, I took the truck out to the field and tried all the various settings to make sure it worked (and especially that it was off when i thought it was). It seemed to me when i turned them to the left, 4 wheel drive was on regardless of turning it on in the cab. When both hubs were turned to the right, 4 wheel drive was off unless turned on in the cab. We went on our trip and after a few hundred miles, I felt a shaking in the steering wheel when turning. After another few hundred miles, I felt it again and there was a noise. There was a Ford dealer next door and I stopped and the service manager came out and said he thought the noise was the rear suspension due to the load and nothing to worry about. After a few hundred more miles when we stopped for the night, when you turned the steering wheel significantly either direction, there was the shaking/shuddering feeling in the steering and a horrible grinding, crunching, scratching, shredding noise seeming to come from the rear. There was a Ford dealer across the street there and I took it there the next morning and it was not making the noise. The tech thought it could be the clutches in the positive traction rear end. He could not get us in until the next day and unless we could be in and out in 1 day we would be stuck there for the holiday weekend so we decided to return all the way home. All the way home ( 700 miles) it made the noise, etc. every time a sharper turn was made when stopping for gas but otherwise when cruising down the interstate it drove fine (just like it did during all the above time). I took it in to the dealer where my nephew works and they said nothing wrong with rear end and couldn’t find anything else. A Ford enthusiast that works there with my nephew speculated it was 4 wheel drive related and he and my nephew checked the hubs and said they were both turned to the left. (I had had a leaking front tire repaired since I had set the hubs to the right so suspect they had turned the hubs). This Ford guy said he looked online and the hubs were both supposed to be turned toward the front. In other words, facing the passenger, to the right and facing the driver, toward the left. They said they did that and the shaking in the steering went away. He attributed the horrible noise to the 4 wheel drive overheating. He said I probably did not do permanent damage but recommended the differential fluid be changed.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
So my questions are: what are the auto settings: turned to the right or both turned towards the front. (To further confuse me, when I was just walking my dogs, I noticed a Ford Expedition with the front hubs showing both turned to the left for the auto setting. <o></o>
Second, do you agree with the diagnosis and is there anything else I should do other than changing the differential (and making sure the 4 wheel drive is not engaged when travelling hundreds of miles at highway speeds. Thanks so much for any help or advice.<o></o>
Jack up one front wheel off the ground. With the dash switch on 2 wheel, the wheel should spin free. Start the truck and put dash switch to 4x4 and try to spin the wheel, you should not be able to move, because its locked in. Now with the engine still running put dash switch back to 2 wheel and the front wheel should spin free after a couple seconds. If it spins free the locking hub is in the auto mode, if it doesn't spin turn locking hub setting and try again. If it still does not turn then the problem is either in the locking hub or with the vacuum that works the hub locks. Could be the locking hubs just need to be cleaned and greased, could be the o-ring seal on the hub lock is bad or a vacuum leak. My hub on one side works in auto but if I switch it to manual and back to auto it won't unlock, so I have to pull the lock off, pull it apart, push in the black bladder in the bottom of the housing and put it back together. It works fine as long as I leave it in auto. Try this on both sides and see what you come up with.
It sounds like you have potentially more than one problem and too many cooks in the kitchen.
First of all the front hub locks. Righty tighty, lefty loosey. In other words, turn them to the right to Lock. Turn them to the left to put them in Auto. Now, just because they are in auto does not mean they are locking and/or unlocking properly. You need to test them.
When they are operating normally, you switch the dash switch to 4WD, the transfer case engages and then the hubs are locked by a vacuum pulse. You switch to 2WD, the transfer case disengages and the hubs are unlocked by a lesser vacuum pulse. To test, you will need to get a front wheel off of the ground. With the key in the Run position, put the switch into 4WD. When the 4x4 light comes on, try to turn the front wheel in the air. The hub should be locked and the wheel should not turn freely. Turn the switch back to the 2WD position and the hub should automatically unlock and the wheel should turn freely. Lift the other side and do the same test.
There should be no problem running the truck with the front hubs manually locked. In fact I would recommend you try it. You will not be in 4WD because the transfer case will not be engaged. If you feel shaking in the steering or hear noise with the hubs manually locked, you most likely have a problem in a front axle u-joint. Especially if you feel the shaking or hear the noise when you turn the wheel. If the noise and shaking go away when you turn the hubs back to auto, and you've tested them to be sure they are unlocked, that would confirm the problem is in the front.
Thanks for the info. I do not have my truck or manual here right now but will do some checking as soon as I pick it back up tomorrow. Let me make sure I understand. First, I could have sworn that my manual says to the right for auto. You are saying to the left on both (like on the Expedition I saw). Second, even though the hubs are locked, if the in cab is not turned to 4 wheel drive, then you are not in 4 wheel drive, right. If that is the case, then I know my in cab controls were not turned to 4 wheel drive, so my 4 wheel drive could not have been engaged and the theories given to me fall apart. I will try to do your recommended checks as soon as I can. Thanks for the help.
Clockwise to lock. Counter-clockwise to unlock. Both sides are the same. I just went out to my truck to verify.
When the transfer case is disengaged, no power is going to the front wheels. The front drive axles, u-joints, differential and drive shaft are all turning, if the hubs are locked, by the wheels. But there should be no power to them and no binding or other noise.
My manual clearly says auto is to the right but you all and the Ford dealership said to the left. I jacked each front wheel up separately and each one spun freely with hub in auto (to the left) and 2 wheel drive and was locked when I switched to 4 wheel and them unlocked when I switched back to 2 wheel. Each wheel also did the same when I turned the hub to locked. My question is - if I had been driving with the hubs locked but the setting on 2 wheel drive - would that possibly have been a cause of the noise. In other words, if your setting is on 2 wheel drive, does it matter if the hubs are locked or on auto. Thanks a lot.
It sounds like your hubs are working properly. That's the good news.
With the hubs manually locked, and the transfer case disengaged, there should be no noise or vibration. If there is, it is usually caused by a bad front axle u-joint. Those are the ones right behind the wheel. You need to get those checked out.
Running with the hubs locked manually and the transfer case disengaged is not a problem. People do it all the time. Mine were locked from November to January, and are locked again, because of the weather. Some auto makers don't even use locking hubs, the front axles, differential and drive shafts just run all the time.
question about hubs i have a 02 f350xl with the manual transfer case and manual hubs. Are they true manual hubs, like on and off or is it always auto and off?
Turned to the left they are unlocked turned to the right they are locked. Everything is manual with the manual system. The ESOF hubs (auto) have a diaphram in them and are locked with vaccum with a manual (locked) override.
Lock the front hubs with the transfer case in 2wd on your truck and try to turn the front driveshaft.(Should not be able to turn it) Now unlock the front hubs.(Should be able to turn the driveshaft now)