I have a 2005 f150 with a 6in lift on 35's with 49k miles on it and i have already had to replace the tranny and now about 1k later im starting to have really bad vibrations coming from the rear end when i reach speeds around 45mph, it feels just as im on the shoulder of the highway on those bumps just not as intense but as i go faster it gets worse and vibrates more....any ideas?

 

what kind of tires? how many miles on them? had them checked for balance?

 

they are nitto terra grapplers with probably 15k on them and yes i just got them all balanced today and said they were just barley out of balance and the vibration is still there

 

this happen to me before but all it was , that i had mud packed on the inside of the rim causing them to come out of balance ... not to sure what else it could be beside something to do with your tires/rims .

 

Check your u-joints.

 

I have already cleaned my whole truck thoroughly and there isn't any mud there I just got my tires balanced yesterday and also took to a shop to have them check the u joints and said they were still good any other guesses??