snowfiend

My truck is at the dealer right now to figure out why the front driveshaft and one wheel are spinning in 2wd. I noticed MPG dropping and a strange front end vibration, jacked up the front end and spun the front wheels. The axles spin as they should, but when I started the engine the passenger axle was still locked and spinning the halfshaft. I then put the rear up and put the truck in drive and noticed the front driveshaft spinning along with one tire, but at half speed compared to the rear. Video here:
Any bets on what is wrong before the dealer calls me up? Posting to help others that may have similar issues, I have 1500 miles left on my powertrain warranty so fingers crossed it's covered!

djfllmn

iTrader: (1)

IWE

snowfiend

That makes sense for the front halfshaft, but how is the center driveshaft spinning? Transfer case issue?

jp360cj

With the front tires off the ground & rear tires on the ground, can you spin the front driveshaft? If so, then I'd also say IWE problem. The front could be spinning in 2wd with all the tire off the ground just from the fluid moving around in the tcase. Kind of like how a manual transmission can spin the rear tires if they are both off the ground and the transmission in neutral.

snowfiend

I didn't think to try and spin the driveshaft by hand when it was in the air, only the wheels. That's a lot of fluid drag to spin these heavy tires!

djfllmn

iTrader: (1)

if the IWE is stuck in then there is no disconnect from the wheel to the front driveshaft..if the axle is spinning the driveshaft will be too

snowfiend

That makes sense when spinning the wheel by hand. With the engine on and in drive though, the power to spin the wheel can only come from the transmission so either its parasitic drag turning the driveshaft (an abnormal amount?) or there is something causing engagement (half speed engagement?) of the front driveshaft in 2wd.

snowfiend

Dealer called, a "check valve" failed and took out the IWE. I'm on the hook for the check valve and Ford is covering the IWE. Says the drag causing the front driveshaft to spin is normal.

Stu Cazzo

Thats a good deal cuz the check valve is only about $15 as opposed to the IWEs $125 or so.

Buy an extra check valve and throw it in your toolbox. Seems those stupid things are always plugging up. It takes a whole 15 seconds to replace.

Enginner5

What is the "IWE"? Figured it out.

Snowfiend, was it making noise at all or did you just notice the drop in mileage?