Hey all,
I've been posting off and on here whenever i get pissed off enough about my truck to see if anyone can help. It's a 78 1/2 ton 4x4. At one precise speed, approximately 33-35 mph, the thing starts to buck up and down. It's not a side to side motion, it's honestly what you would call a 'gallop'. It's been doing this for over a year and i've done everything i can think of to stop it. the transmission was rebuilt about a year ago, had no effect, the axles have been swapped with new gears put in, new calipers, pads, rotors turned, i've had 2 sets of wheels and 3 sets of tires all mixed and matched on there at some point in time with no effect at all. I had one end of the driveshaft replaced cause it was showing a little wear. I have no damn clue what is causing this vibration. I have asked every gearhead and mechanic i know and no one has any ideas beyond a tire being out of round or rotors needing to be turned (which i have already tried). Any input or advice would be greatly appreciated.
Thanks again TB