I've been having a driveshaft slip yoke clunk on initially take off for about 6 months now on my 2005 F150 with the one peice driveshaft. I've removed the driveshaft twice now and greased it. After each greasing the clunk stops for about a week. The last time I slid the driveshaft out of the tcase a small amount of ATF dripped out. I'm wondering if my output shaft seal could be leaking and the ATF is washing away the grease on the splines of the driveshaft? Does this make sense? And is the transfercase output shaft seal hard to replace? Thanks

 

Nobody has tackled this seal before?

 

The clunk is getting really bad. It now also does it when shifting from first to second somethimes. I pulled the driveshaft again yesterday to grease it and there was a fair amount of ATF that leaked out once the driveshaft was removed. I've been putting in the Ford recommended grease and this last time it didn't even seem to help at all. My only guess is the ATF is washing away the grease. Is the transfercase output seal something I can tackle myself? Or do you guys have any other ideas what is going on here? Thanks

 

Not many of us would mess with our transfer cases. I will change out the fluid but other then that I let a professional handle it.

OK i assume when you pull the shaft off the grease appears to be gone. But does the shaft still seem like it is oiled or something? If the ATF fluid is leaking out and washing it off there should be some sort of oily residue still around or at least it should feel a little bit slippery. Have you checked the fluid level on your transfer case recently?

 

When I pull the shaft out there is still some grease on it, but there is also a small amount of ATF that drips of the splines. I changed my transfercase fluid about 7 months ago and filled it to the proper level but haven't chacked it since.

 

This is normal that clunk is not fixable... even with a brand new driveshaft. You're paying to much mind to it... Mine does it to... and I got a brand new drive shaft... also when you pull it out, tranny fluid is normal on it.

 

My 01 does it also....I put the Ford PTFE grease in there and it went away for around 2 weeks, now its back again....Mine also has some tranny fluid on it, but not much. It Think on my 01 case that is, all I have to do is take off the tailpiece to gain access to the seal, but like otheres have said, its a commmon problem that we have to live with....If the leak was a problem you would see tarnny fluid leaking on the ground