I just happened to grab the wrong knob the other day and flipped it into 4HI before I backed it out of the shop. I got to about 45MPH and there was a large amount of vibration in the front from there to about 60 MPH. Do I have a bent front drive shaft or something??? Have not been off road or used the 4WD since last winter to plow snow a couple times. Thanks for any input.

you should still be under warrenty.. id take it to the dealer and let them figure it out

I get what I would call a mild to medium vibration in the same MPH range but only under acceleration. I leveled my truck and just chocked it up to the increased CV angles.

Same here----when I accelerate. I have no lift done---just the bars up a bit to carry the front a little better. I would call mine a medium to medium high vibe. I will be going in for some recall stuff.

Are the gears front to back an identical ratio? I seem to remember something about fronts being 4.10 and rears being 4.11? Im sure someone will likely chime in and confirm or denounce that. At any rate, you do not want to run your truck in 4wd on bare pavement, it will put tons of stress on your transfer case. If your front tires show a different amount of wear than your rear tires, your tires are essentially a different overall diameter from front to back or vice versa and obviously want to turn the axles at slightly different speeds, and with the axles lock together something somewhere in between is going to want to bind. Having said all that if it is shaking as bad as you say it probably is exposing a worn part somewhere and you should talk to your dealer about it.

Are the gears front to back an identical ratio? I seem to remember something about fronts being 4.10 and rears being 4.11? Im sure someone will likely chime in and confirm or denounce that. At any rate, you do not want to run your truck in 4wd on bare pavement, it will put tons of stress on your transfer case. If your front tires show a different amount of wear than your rear tires, your tires are essentially a different overall diameter from front to back or vice versa and obviously want to turn the axles at slightly different speeds, and with the axles lock together something somewhere in between is going to want to bind. Having said all that if it is shaking as bad as you say it probably is exposing a worn part somewhere and you should talk to your dealer about it.

I read something similar recently. Since the front and rear gears aren't the same diameter, they aren't exactly the same ratio. Close, but not quite. I spent a little time on Google but couldn't find any info on it. I too am wondering if this is true and if so, how much of a difference is there.