i've noticed a slight vibration under load or accelerating up a hill. it sort of feels and sounds like when my pilot bearing went out in my firebird with a 4sp man. but my truck is an auto. i'm thinking maybe the drive line u joints and hoping not the rear end. anyone else have any thoughts ideas or suggestions?
thanks

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'95 2500, auto, 100k miles, k&n air filter so far.

 

i had something like this a year ago...turned out to be my carrie bearign for the rear axle (i think thats what it was called)...anyways get under the truck and right look at the lil donut unit that hold the driveshaft ...the rubber in the middle was completely cracked and worn out on mine

 

also does it do this when locked in 3rd? or gear doesnt matter...if only when locked in 3rd then it could be torque converter shutter otherwise dont worry ands check the carrier and driveshaft u-joints

 

Mr T has is right except if you have a regular cab with one piece driveshaft there is no center carrier bearing.
Just trying to help you from looking for something that isn't there.

 

I've got a 2006 3500 doing the dame thing, but more severe, pulling about #13,000, dealer says its the angle of attack n the drivetrain, another says its the clutch springs bad in the auto tranny, plan to weigh the camper this week to check exact weight if overweight as the dealer is trying to say.
still searching..

 

I believe you have the infamous Torque converter shudder. Mine developed that after i put in my #8 plate.It would shudder everytime it went into ovedrive underload, or pulling up a grade unless i backed off the pedal a bit. I lived with it like that for a year or so and just backed off a bit when it started a shift kit helped it a bit by increasing the pressures.My new triple lock has taken care of that problem.