So, in the continuing saga of "this should bolt right in" and then reality tells you no
I had the OE Aluminum driveshaft out of my Lightning also sitting on the shelf. The spec sheet says the Expedition has a 119" wheelbase and the Lightning has a 120" wheelbase... I figured that must be rounding and surely the driveshaft would fit.... laid them side by side, the Lightning one was in fact a tad longer, and I'm still telling myself "yeah but the slip yoke probably makes up for it" and tried it anyway.
Nope, no dice. Even with the slip yoke bottomed out in the transmission (which is already a no-go as then any suspension compression would beat your trans to death), it wouldn't bolt up to the axle.
Well, time to clean up this OEM steel DS enough to be presentable for now. I wanted the lighter weight aluminum, I might still get a custom one made down the road (if it fits, it's pretty tight in there), but for now let's get it rolling.
Eagle eyed readers may have noticed the slip yoke on the Lightning driveshaft is larger. That's because the Lightning 4R100 uses the diesel spec output shaft and tail housing. My first time dabbling in u-joints, how bad could it be? Pretty messy if you're not used to it! Took the slip yoke off the Lightning DS to get it on the Expedition one.
I wire wheeled the shaft to get it cleaned up.
Followed that with a coat of black primer
Finally, a few coats of rustoleum gray enamel
I didn't get any then of pics of the new u-joints going in or of it installed, will have to take some for one of the next updates. I was pretty happy with how it came out, it looks much cleaner down there now.