hey all,
I was gonna start on this today, but I got the wrong u-joint from rock auto. They sent me a moog 321, but I can see it's way too small for our 2007 f550 V8. After much searching it looks like I need to order a moog 424. If anyone can confirm I would be grateful.
My main concern is the gear oil or transmission fluid leaking from behind the u-joint. Can anyone tell me the name of the seal I need to replace so I don't order the wrong one? A part number would be very helpful. Thanks

 

Dana Spicer 2014835. But, it really looks like the inner axle seal is leaking.

 

Ya inner alxle diff seal leaking. Check diff level now..you have to pull the axles and diff to change those....lotta work..

 

I just had all four axle wheel seals replaced on a 2016 with 39,000 miles. This is NOT GOOD.

The pic above looks definitely the inner diff axle seals. The seals are in the front diff and leaking out.