Does the vibration come and go at certain times? Mine ONLY vibrates under more than 50% throttle and when the TC is not locked up and really can't feel it much in 1st gear but a lot in 2nd and 3rd and sometimes in 4th if i'm pulling a trailer with a load.

 

If I stomp on it from a dead stop I can feel it at about 30 to 40 mph, I also feel it when the truck is under load and if I get on it while on the freeway or climbing any kind of incline (hence under load), I have yet to pull my 23ft travel trailer and right now would not attempt it. It is super irritating because I find myself driving differently, compensating for it so as not to do any possible damage elsewhere.

FYI... I have a 2005 FX4 Super Crew with 113,000 miles on her. I drive her hard but I baby the shiz out of her also, if that makes sense.

 

'The rear pops when you turn tight in a parking lot. I've been told this is normal because of the ratcheting LSD? Is this true?'


Change the differential oil. use the Ford-specified oil + the Ford additive for the LSD. LSDs have service intervals, unlike the regular rears which are filled with 'lifetime' synthetic oil.

 

Update: third new torque converter and 1st new flex plate, all is good vibration gone. The shop told me the ordered the 3rd TC and had it specially balanced for my truck, whether that is true or not I don't know but the flex plate was replaced this last go around also, anyhow she's running smooth now. Happy that she's finally fixed but not thrilled it took 3 times.

 

You know i had a broken leaf spring that once i replaced on my 2007 f150 i started getting a vibration. I ended up replacing the u joints in the rear driveline and having it balanced. Truck is so quiet now i can hear myself think. Maybe unrelated but worth checking out.

 

I'm all dialed in now but thanks for the info.