bucking 6.0

[biscayne]

I rode with a buddy today in his crew cab stock except lift 6.0. Something that really shocked me was a intermittent "bucking" when he floored it. Rapid acceleration was fine but if he stomped it the motor would intermittently kick back, non rythmic. Just curious, injector dumping out, computer? anyone have something similar they solved?

[mhatlen]

Odds are it's a injector issue possibly a weak ficm but not always especially when lifted.
Take a close look at the carrier bearing rubber isolator, if you pull on the driveline sideways and it's moving around that's your problem. Take a look at the U/Joints as well, my truck needed carrier and U/Joints at 60K miles and engine is stock and I don't push it hard at all. When the truck has been lifted and you run big tires 36" or larger the driveline is under a huge load and it will wear out much sooner than in a stock configuration.
Check that first, usually you should have a shudder when accelerating away from a stop when the carrier bearing is hopping around in the frame. It will also shake when at highway speed under light to moderate acceleration,full throttle will usually pin the brg to one side from thrust and will shake again when letting off throttle.
Good Luck with it..............Around $100.00 will do all 3 u/j,s and carrier w/ domestic parts.