My truck shakes under acceleration but as soon as I let off the pedal the vibration goes away. I checked my brakes but they are new, u-joints are also new. I had a shop rebuild m y front differential and drive shaft a few months ago. Could a bad tire do this? I h ave a 6 inch lift and 325 tires. Any help is appreciated.

 

You could rotate the tires to see if the vibration moves, and take out the driveshaft and drive in 4x4 to eliminate rear driveshaft issues. Do you have a long bed with a center carrier bearing?

 

I did. And im not sure if the rotation moved. But the vibration is worse. To the point were I dont want to drive it. It is a short bed.. ill try to take out the driveshaft next.

 

Is there any whining from under the truck... or in front? Is the vibration in the wheel or in your seat? Is it there if you let off the throttle at 65 MPH and hit the OD button? Is the vibration forward and backward, or side-to-side? What happens in a hard left turn or hard right turn? What made the vibration get worse?

 

I just had the same thing where I had vibration under load in the 35-45mph range, but if I let off the gas it went away. Plus a little clunk when putting in forward gear. Turned out to be the rear driveshaft universal joint at the rear differential was toast. Changed both ends of the shaft (short wheel base no carrier bearing) greased the splines under the bootie and no more noise or clunk.

BTW, there was no noticeable slop in the shaft from underneath by hand in neutral which threw me off a little at the beginning and started me thinking too complicated.

 

Honestly I dont even know whe the vibration is coming from. I feel it everywhere. When I make a hard turn it feels like is going to fall apart. Last summer I replace the driveshaft ujoints and the joke that comes from the differential. As soon as I let the pedal go everything gets smooth. I work all day today, but ill check the joint on the driveshaft tomorrow, maybe is loose? I hope so. Ill let you guys know what I find out

 

Also it has a clunck when I put it in drive. Never did it before. How can I know if its the driveshaft.

 

Clunk when you put it into drive is either driveshaft u joints or the spline on your drive shaft needs greased.

 

Could the shop put the drive shaft in a different position as in they forgot to put a chalk mark on it so it goes back the way it came out and now its worn out the u-joints and under load it vibrates?

 

I did the job myself and marked everything. Its been fine for the past year. Ill probably have to take it the shop. Unless I can find whats wrong tomorrow.

 

Clunk when put in gear, vibration under acceleration, goes away when coasting...... dollars to donuts its a u-joint....

 

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I can't get any play by hand but the wheels are still on the ground.
Thanks for posting, I'll try this first.