Hey, I know this may sound silly but I need some beginner level 4WD info.

Just picked up a 1980 F250 to use while I am changing drive trains in my 1960 (going to a 302/C4/9").

I have never driven 4 wheel drive before and cannot find this basic information available on the web.

What is the maximum recommended speed in 4WD Low and 4WD High?
Can you shift from Low to High while moving or must you come to a stop first?
What is the purpose of Neutral while in 4WD? I would assume it is not the same as not having the hubs locked.
Any other basic information would be appreciated as well. Obviously I do not have an owners manual on the truck.

The u-joints on the front wheels are noisy. They have a little play and you can move them by hand. They rattle a bit when in 4WD moving but not noticeable when not in 4WD.
Are these difficult to replace? Torch or press required?
Picked up a cheap chiltons manual but it is so generic that it is only useful as reference if you generally know what you are looking at already.

Thanks.

 

You will find 4 wheel low is useful only for off-road heavy pulling. It basically turns your truck into a farm tractor. It's selection is down low past the "n" so you need to be stopped.
You can shift in and out of 2h-4h IF THE HUBS ARE LOCKED IN. With the hubs locked in, the whole frontend is being turned by the wheels, so the transfer case will slip in and out easily.
The neutral on the transfer case is useful if you want to tow the truck for short distances.
The front u-joints are a real pain to replace. If you are going in to change them, make sure your ball joints are in excellent shape, since you might as well change them while you are in there if they are not.
I ran my 4wd for a couple of seasons with a bad u-joint. I nursed it along, only locking in the hubs when I needed the 4wd, and then unlocking the hubs when I got on the main road. I wouldn't put too much strain on them till you get them replaced.

 

Top speed in my 84 F-250 in 4low is less than 25mph, with the motor at about 4000rpm, and the t-case whining away. I would really recommend staying below 15mph. The u-joints aren't bad, but since you have never done them before, either have a friend who has help you, or take it to a shop. You may have to use a torch on them, depending on how rusted the center cross is. You cannot shift between high and low while moving, you must be completely stopped, and the tranny must be in neutral. You may feel a little gear crunch, but that is ok. If it grinds, push the clutch in, or put the tranny in park. Have fun with your new 4x4, you may not want to get rid of it when you finish the other one!

Jared

 

Nightowl

I own the exact same truck . I have the original owners manual . If you have any other questions let me know .
Is it a XLT , Custom ??? Is it a full-floater or semi-floater rear ? Full floater will have a little hub with about 8 bolts holding on a cap in the center of the axle shaft ( best explanation I could think of



Jeff