I have decided to install a rear axle assy from a 2001 explorer, but when I found the axle assy the center pumpkin is off center by 3", so I thought the axle must be from a 4 wheel drive. However the salvage yard says their is no difference in 2w or 4w?
This off center 3rd member just doesn't seem right to put put in my F1.

Any help with what is best to do would be greatly appreciated.

 

Slight sideways offset due to non-centered pumpkin is common on many rearends. The offset pumpkin actually makes the driveshaft be straighter down the middle of the truck. Think about the offset of the ring gear and pinion from the center of the rearend, it is about 3 inches.

As long as the total U-joint angle is not too far off, you are fine. I would guess that with your truck being a fairly long driveshaft, the offset is not a problem. The driveshaft does not know what the offset is up/down or sideways, it is just the angle it is operating at.

If you do not like the offset from a visual standpoint that is a different issue.

 

U-Joints in a driveline need some offset to distribute the grease inside them. If there was no action in the U-Jpint then the lubricant would remain static.

 

Just a note on the explorer axle. I also installed one, and the offset r+p isn't an issue. As 38chevy said, the u joints don't know if the angle is up and down or side to side, they just see an angle. Remember, the axle tube is 3 1/4", slightly larger than standard, you'll have to adjust the spring perches with a grinder. Because the width is slightly narrower than stock, you may get some tire interference with the bed if you lower the truck much. My truck is 4" lower than stock so the bed is between the tires, not above it. My 16 x 7 wheels, built to spec, came in with 1/4 " more backspace than ordered which caused the sidewalls to rub the bed. A standard offset wheel should have enough clearance, but it's something to check before writing a check for wheels and tires. In my case billet spacers did the trick and let me match the bolt pattern to my jag front end. All's well that ends well.

 

When you installed the explorer axle did you put spacers between the springs and perches to lower the truck? I'm not sure what rim size to go with, but I was not planning to go lower than just the spring directly to the perch. My plan is to use the original 51 F1 springs,
Thanks
Roger