Hi guys, I have a 2009 FX4, 6" Skyjacker lift, 20" KMC Monster wheels and 35" Pro Comp Extreme AT Tires. This truck was lifted at 300km so its always been modified. I have a bad shaking in the seats and bed bounce. I have had everything checked tire balancing, alignment, drive shaft, tire belts etc. Everybody says it must be the wheels and that maybe the green hub rings on my monsters don't fit 09 F150 great. Anyone running these wheels and find the truck is shaking as well? It happens at about 100km and up (60miles), Im to the point of just accepting it, but its vibrating everything loose i think.

 

highway vibration is probably wheel balance, have you taken it somewhere else to verify the shop's work

whats your pinion angle look like? 2 piece driveshaft?

 

I have had the tires checked at 3 places they all say they are fine. I also replaced one of the tires as i thought it might be a issue with one, still the same. Not sure about the drive shaft, the lift installer said it was fine.

 

might also ask for a "road force balance" at your tire shop, this will check for tire out of round

 

yeah like patman said, you should have them road force balanced or trued.

 

Ya I had that done already. I have even had them dismantle the tires from the rims and spin the rim. Could it be the plastic hub rings?

 

had the same problem with xd monsters. got some hub centric pro comps and it's all better now. road force test said they were ok but something in them was messed up.

 

long shot since its a newer truck but,
how are your front end components, balljoints, tie rods? (altough alignment place shoulda checked) I had a BAD vibration in seats and everything even after getting everything rebalanced...changed all 4 ball joints and tie rod ends and it drives smooth. Everything was loose like a hooker when i took them out.

 

If you still have your factory wheels stick them on and see if the truck still does it, or borrow someones. If it doesn't then you know is a wheel/tire issue.

 

Did you ever find out what was causing this? I am having the same issue but with a set of MotoMEtal wheels which are hub centric, and running 35 inch General Grabber AT/2's. i havent had them Road Force balanced yet, but the was back multiple times to the shop that installed them. There isnt any issues with the stock wheels, but these start shaking at 60mph and up!

 

Its most likely your wheel/tire balance. Either that or your driveshaft.

When I lifted my truck the second time, my driveshaft wasn't long enough to cope with the lift and so I had to get that lengthened. Before I did, it had a wicked vibration in between 40-50mph. I dont know if that applies to the newer trucks, but you can check to see how far it is pulled out of the trans and you will know.

 

The lift i eneded up going with was a BDS 6 inch, which came with the drive line extender. Also i was using the stock wheels with this lift for about 3 weeks, with no vibration issues, then one i put the 35 inch generals's with Motometal wheels...bam...i got the steering wheel shake at 55+ mph.

At first i thought it was b/c i wasnt runing a hubcentric ring, but found out that the motometal 957 wheels are hub centric since they are made for jsut Fords due to the 6x135 bolt pattern. I dont know if a road force balance will do the trick or not