I agree - it's very difficult to tell where it's coming from but I would say mid not rear.

After speaking with the service manager at my dealer, the disassemble, re-grease and reassemble is the gist of what they were going to do. Keeping my fingers, toes and eyes crossed this does it and no more is needed.

 

Ok got my truck back and they disassembled and re-greased the slip joint. I drove it about 10 miles home in stop in go traffic and it appears to have corrected the thump but I will give it a few days of driving until I call it fixed.

I will say this the Ford adviser and sales man seemed to push the issue and go the extra distance to make sure the issue was fixed but the technician was very fast on calling the thump "normal". (the things flat rate mechanics will do/say to avoid warranty work and make a buck is amazing, I know I used to be an honest one)

I hope this was the issue! If it proves to be effective over time but eventually comes back I will be doing the slip joint/grease fitting mod like Ford should have completed at the factory.

 

Thanks for the update. Yes, perhaps a drill and fill is in our future...

 

sounds good that you got it fixed.

 

Great news! I am glad that things are looking more promising. Let us know as you drive it more. Any chance you can share the name of the Dealership/Service Advisor, so when I bring mine in I can reference your dealership in case they have questions? -Jon

 

The slip joint is a simple thing and most trucks never even have a problem with it. A little grease there should last forever. I don't know what they were so concerned about.

 

So, greasing the sllip joints has fixed at least two (drperfomance and ruschejj).
Looks l like I need to press the issue again with my dealer, but may be a couple weeks before I have time. I would think that would be something they could do in a couple hours, instead of having to leave the truck for a couple days....but we know how that goes. Thanks for all the info guys, and keep us posted on results!!

 

CorkyNM - You're up next...let us know after you get the truck back next week! Have a good weekend everyone.

 

I hate to burst all of y'all's bubbles, but it will come back. I've had mine greased once, done it myself once, and had all new driveshaft, slip joint, u-joints, etc. installed. Each time, the bump is gone for several thousand miles and returns.

I have 10k or so on my new driveshaft and slip joint and I am about ready to drill/tap a grease fitting into it. I'll probably do two, one on each side of the slip joint.

 

I thing there is something going on with your splines, most trucks never have the problem.

 

Will do, you can count on it.
I paid a lot for this truck and I hate noises. I will be pulling a 13,000 toy hauler and I can't afford to wear something out prematurely. Does anyone have any insight on the long-term effect of this issue? Splines wearing out, drive shafts laying in the road someday, transmission problems, etc.?

Signed,
Worrywart a.k.a. CorkNM

 

It should last forever but I just think your splines weren't machined right (just binding). I wouldn't worry about it.

 

I will admit that it more that worry - I hate that bump feeling whenever I hit the gas, I really do. I just rolled over 2000 miles, and it feels like 100,000. A brand new truck should not make me feel this way. When I hit the pedal, it should be right there, no bump, no nothing but turbo power man. I want it gone, pure and simple.

 

Any time the service department starts throwing out the term "normal" tell them you want to take a ride in one of the new trucks parked out on the lot (they can even drive) and show you the same thing.

 

No, this is normal behavior. It even has a name. "Super Duty Clunk" Some trucks never get it, but just because you do does not mean something else is wrong.