I know there's a tsb for similiar but it's not a drive shaft sounding clunk noise like others describe. Taking truck in on Thursday, wondering if anyone got this fixed. Already had new clutch packs in at 3k for chatter around turn. Did it slightly back then but getting worse now at 15k. It feels like a pinion gear slips under medium acceleration from a stop but only when cold. ( don't think that is possible though ) Happens straight or during left or right turn. Does it a few times each time you accelerate - and only from a stop during take off for first 10-15 minutes driving truck. After I drive 1/2 hour home from work, it is fine. Maybe differential fluid low and is ok after it heats up? I thought it may be a leaf spring or bushing at first but this would not go away after warm up. You can hear it and feel it. Only happens in forward, not reverse. Hoping for any info so I get get this fixed before I get my xcal2 ( should be here soon !).

thanks

 

i am having the same problem you are describing as well. However i wouldnt call it a creak/thump.. it is more of a suction popping sound.. i really dont know how to describe it.

 

Thanks for reply bushtree. Ya, hard to describe the sound but multiple 'pop' or 'snap' sounds can be heard and felt from the rear area under easy to moderate acceleration from a stop. Way more pronounced when truck is cold. I'm going to park at dealer tonight and take them for a ride in the am so they will definately hear/feel it. I'll let you know the outcome....

 

yes! I think we are trying to describe the same problem. It has been bugging the hell out of me for the last 6 months. Please let me know what you find.

 

hey bushtree, took tech for test ride yesterday morning and truck did it in parking lot for him, just like described above. We then drove to back of lot and drove in tight circle a few times ( left and right ). They already replaced clutch packs a while pack and was sure that was not the problem this time. It was good that I parked it there over night, it allowed him to hear/feel what it does every morning ( and night when I first leave work ) for me. Also, it has been doing it for about 6 months as well, feels/sounds like it was just getting worse now with it colder in the mornings.

We talked about the slip yoke lube but like described in earlier post, it was more of a pop or snapping noise and feeling - multiple times each accelleration, than a hollow drive shaft 'clunk'. Also talked about the shim drave shft angle TSB.

He put it up on lift and within 20 minutes, he had the rear out and back leaf springs - ( I was at the parts counter ordering skid plates for it and saw my backend off it ). Could't find any issue here but it actually ended up being repacking the slip yoke with grease. I picked it up early evening last night so truck was cold when I took it. It is totally quiet and smooth now, you could tell as soon as I pulled out of the parking spot it was fixed! I only hope it stays that way!

Good luck with yours man...

kevin

 

Good luck to you too - hate to be the bearer of bad news but ---- my lubed slip yoke lasts about 5 months maybe - it has been lubed with ford's special teflon grease 4 times and its back again. I asked if there was a permanent fix and they said no. Kind of disheartening because that clunk drives me nuts.

 

so its was the slip yoke that needed to be lubed?

I dont have the time to leave my truck there and show them what i mean so its hard. If this was the problem mabey i can just ask them to do it since there is a TSB for this correct?

Thanks,

 

yeah the lubing only lasts about 4 months max, and then it'll come back

 

Has anyone actually found out if the slip yoke noise causes any long term problems? I know that there have to be some trucks out there getting some miles on them. I just hate to take my new baby in for the fix. I've had damage of some type every single time I've taken a truck in for service.