6.4l bucking

[Red Ripper]

09 F350 6" pro-comp lift / trac bars, built engine & tranny gear head tunes 140,000km (87,000k miles)

Truck has been fine for the last 20k now I'm getting bucking between 75-80km/h (45-50mph) if I'm on the throttle or not also has a slight shake at 110km/h (70mph) any ideas?? I was thinking U-joint or maybe pinion bearing ?

 

[Powerstroke Man 6.4]

09 F350 6" pro-comp lift / trac bars, built engine & tranny gear head tunes 140,000km (87,000k miles)

Truck has been fine for the last 20k now I'm getting bucking between 75-80km/h (45-50mph) if I'm on the throttle or not also has a slight shake at 110km/h (70mph) any ideas?? I was thinking U-joint or maybe pinion bearing ?

Sensitive pedal LOL all my trucks do that even my 7.3 did it. I hate it I get pissed off when it does that especially going over bumps.

If that's what your talking about.

The shake

Tires?

Could be the U joints could be anything

More drive train experienced people will chime in.

 

[JrStroker]

Interested in this. Mine does it too. 6 inch lift and 37s. I'm thinking it may be the carrier bearing.

Cory Anderson

 

[Red Ripper]

I had the drive shaft re-balanced as well. it's funny it just started doing now?
Going to get the tires re-balanced tomorrow
What about a one piece drive shaft I had one in my 04 with 8" of lift and it worked awesome but this truck has a lot more power??