HI, I am a new(used)owner of a 2008 F250 SD Lariat V10 4X4 crew cab short box automatic with 70000 miles, I bought from a Ford Dealer with extended warranty, pure stock, I road before I bought and everything was fine, 4000 miles later the truck developed a wierd thump, but actually thre is like the center support bearing is loose, when I take off normally I feel like the driveshasht is loose and also when I am slowing down from second gear to first gear and I apply the brakes lightly, I checked the center support, motor mounts, trans mount, u-joints, and they are ok, it feels like something is sliding when taking off and slowing down, only in first gear, thank in advance for your help and support. Jesus.

 

It may just be that your driveshaft slip yoke just needs greased. It tends to dry up since they weren't greased very well to begin with, then it sticks and will give you a feeling like your transmission is slipping a little bit. It's not a difficult job if you decide to do it yourself instead of taking it to the dealer. All you have to do is undo the front u-joint (make sure you index it first) and remove the boot clamp over the slip yoke, and slide the slip yoke apart and put some good quality grease on it.

 

Might be the slip yoke in the driveshaft needs greasing.

 

If you're careful in removing the clamp it can be reused, or cut it and use a zip tie. Ford used PTFE lubricant in the slip joint. A 3oz. tube from Ford costs about nine bucks, you'll only use 1/4 tube. Be sure to index the shaft to install in the same location.

 

To:Northwindone,Jh818, and Koestner, thank you for your advise, for the next six days we are going to be out of town, but as soon we get back I am going to do the dreive line like you guys told me to do. It sounds like that might be the problem. I will post the results. Thank you again. I knew I can count on you guys for help. 2006pelon.

 

Hi guys, I came back from our little vacation, we went to Vegas for a few days and I stopped at two different Ford Dealers to get the slip yoke lube like you guys told me to and they did not have the 9oz. tube, they only had the one poud small can so I bought it, $45.00. I got home Sunday and the first thing I did was to mark the driveshaft, removed it, clean the splines, and put the "blue lube" on the splines, put it together, lined up the marks, road tested the truck and "THE MOVEMENT WAS GONE". I was so happy. Thanks to jh818 and also koestner, you guys were right. Thank again. 2006pelon.

 

Hi northwindone, thank you for your help, you were right, marked the driveshaft, lubed the slip yoke, reused the clamp, put it together and it perfect, Thank again 2006pelon.

 

Glad we could help, and thanks for posting a follow up. It's always good to know what fixed someone's problem. I'm just happy I can help someone else after getting so much helpful advice on FTE.

 

northwindone, I was so happy after I repaired the problem, specially when a mechanic told me that it was possible that the torque converter was going bad, thank you again. 2006pelon

 

Glad we here could be a help with the problem,reps to you for a job well done.