Drivetrain Issues:
* U-joints (universal joints): Worn or damaged U-joints in the driveshaft are a common culprit. They allow for angled power transfer, but when worn, they can cause vibrations, especially under load (acceleration). This is often felt more strongly at higher speeds or under heavier acceleration.
* Driveshaft imbalance: An imbalance in the driveshaft itself can cause vibrations. This can be due to damage, bending, or even improper installation.
* Differential problems: A worn or damaged differential can create vibrations, particularly under acceleration. This could include worn bearings, gear damage, or a problem with the pinion gear. A whine or other unusual noises often accompany this.
* Transmission problems: Internal problems within the transmission (worn gears, etc.) can transmit vibrations to the drivetrain and cause shaking, although this is less common than the other drivetrain issues.
* Wheel bearings: A worn wheel bearing can create vibrations, but usually this manifests across a broader range of speeds, not just under acceleration. However, a severely worn bearing *could* cause increased vibrations under acceleration's increased load.
Suspension Issues:
* Worn suspension components: Worn shocks, struts, bushings, or other suspension components can allow excessive movement, leading to vibrations, especially under acceleration where the suspension is more heavily loaded.
* Uneven tire wear: Unevenly worn tires can cause vibrations at various speeds, and this could be exacerbated under acceleration.
* Loose suspension components: A loose bolt or other connection in the suspension can create shaking.
Other Possibilities:
* Engine mounts: Worn engine mounts can allow excessive engine movement, leading to vibrations that are felt throughout the truck.
* Exhaust system: A loose or damaged exhaust system can create vibrations.
Diagnosing the Problem:
Pinpointing the exact cause requires a closer inspection. Here's what to consider:
* When does it happen? Only under acceleration? At a specific speed?
* Where is the shaking felt most strongly? Rear end, steering wheel, entire truck?
* Are there any accompanying noises? Whining, clunking, banging?
If you're not mechanically inclined, taking your truck to a qualified mechanic is recommended. They can properly diagnose the issue and make the necessary repairs. Ignoring the problem could lead to more serious damage and potentially dangerous driving conditions.
