I have a 2000 F350 SC 76,000 miles on it. Back in 2001 when I would pull away from a dead stop the truck would travel about 5 feet then there would be a noticably clunk (no sound just the feeling) from the drivetrain. The dealer said it was a joint in the drive shaft which they fixed by using epoxy. I remember they had to keep the truck overnight since the epoxy needed time to cure. Anyway it worked the truck didn't have any slop in the drivetrain for years.

But then the problem (or a similar problem) came back a few months ago. Consistantly when I would pull away from a traffic light, clunk. A couple of weeks ago I changed the auto tranny fluid and filter for the first time. Yeah I waited too long. Anyway the clunk went away. Well almost went away. Now when the truck is stone cold no clunk as the temp goes to normal range the clunk comes back. Not as bad as before but it is there.

So what I wonder is why did a fluid change help with this problem? Is the TC going bad or is it something else? Do you think using Mobil 1 syn fluid would help since it is less temp sensitive than dino fluid?

The reason I put off the fluid change was I was confused and believed the fluid din't need to be changed for 100,000 miles. My mistake.

Thanks for your help.

Jim

 

I would grease the slip yoke if you have one.

 

Thanks for the reply and I will grease the yoke as it does seem to be a common problem with these trucks.

But trust me that before I changed the trans fluid and filter the truck would thump everytime I drove off. Since I changed the trans fluid and filter it never thumps when the truck is cold. I have to drive for some time, it seems long enough for the trans fluid to get hot before the thump comes back. And even then its not as bad as it was before the fluid/ filter change. Since the fluid was changed it's consistant, truck cold not clunk, truck hot it clunks. This problem has something to do with the transmission and the new fluid did something to help fix it. But I don't know what.

Thanks
Jim

 

Here's a link for ya'. Many others who used it have reported clunk-free driving. Common problem.

http://www.eurekaboy.com/f250/slipjoint.htm

Good luck!

 

My guess is that somehow the new fluid softened the shifting or something like that... Seems silly I know.