thump

Nice.. someone that actually used the search box instead of starting the 5,726th thread on this topic.

Sounds like the clutch packs. Good luck man, let us know how it turns out.

wilthis

Got it back from the dealer (third time), this time they did replace clutch plates. (Clutch plates binding).

Got it fixed under warranty (just made it).

Seems OK now - better be!

bloodvette

my rear is doing that too. First thing I did was change the diff fluid, it didn't stop the shuddering (with one bottle of friction modifier). so I added a 2nd bottle of friction modifier and it has almost completley quit, but still doing it a tiny bit. I'm sure my clutch packs are also in need of replacement. I also have observed that it does it on warm days and not on cold days. I bought it in the winter so I am willing to bet the previous owner had this problem and deliberately traded it in in the winter so it would be unnoticed.

rhicks20

My 04 did this for a few months before I made it by the dealership to ask about it. This happened a couple years ago. They gave me a bottle of the modifier and told me to give it 300 miles to adjust. After a few days it calmed down a good bit. Two weeks later it was gone and hasn't returned. I replaced the driver side axle seal last fall and replaced the fluid and added a bottle of the modifier and haven't had any issues since then either.

sportsmen

Can you buy friction modifier at the store ? Like a walmart or parts store? And will i have to drain some out or will it all fit? THANKS

sportsmen

bump

travisrouse

I also changed my diff fluid. Replaced with Ford 75W140 fluid and 2 bottles Ford friction modifier. Vibration still exists after 2000km of driving. Its like LS clutches arent engaging/disengaging properly during low speed sharp turns (parking lots, merging, etc). When diff is cold (first few turns after start up) vibration isnt as noticeable. Is only option replacing LS clutch packs?


06 FX4 SCREW 5.5' BOX

f150keller

Travis, have you fixed the problem with the clutch packs? If so let me know what you had to do, I'm having the same isue with my 1999 4x4 F150

ham944

My 2006 Supercrew exhibited that shudder during start from stop while turning. I added the modifier without changing the fluid. Seemed to help but did not eliminate. Have not had time to change the fluid. Last week I was backing up in a circle on concrete, 105 degrees outside, and the back end bound up. I figured something in the clutch pack gave out. The truck would not back up any further so I put it in drive and pulled forward. That is when I noticed that I must have bumped the switch into 4High. After putting the switch into 2wd everything was okay. What is interesting is the shudder on starting has completely disappeared.
I am not going to say this is the fix for the shudder, but I am just putting it out their as FYI. Can anyone give me a reason why it makes sense.

jetpuck73

Do I have to take the cover off to add the Ford friction modifier?