* Driveshaft(s): A worn U-joint in either the front or rear driveshaft is a very common cause of vibrations, especially under acceleration. The vibration can transmit through the entire drivetrain. Inspect the driveshafts for any visible damage, play in the U-joints, or binding.
* Differential(s): Problems within the front or rear differential, such as worn bearings, damaged gears, or low differential fluid, can cause vibrations that are felt throughout the vehicle during acceleration. A whining noise often accompanies differential issues.
* Transmission: While less likely to cause a simultaneous front and rear shake, a failing transmission can contribute. Internal problems within the transmission could lead to vibrations that transfer to the drivetrain. Check the transmission fluid level and condition.
* Torque Converter: In automatic transmissions, a failing torque converter can cause vibrations, particularly during acceleration.
* Tires and Wheels: While less likely to cause a *simultaneous* front and rear shake, severely unbalanced tires or damaged wheels *could* contribute. Check for any obvious damage to the wheels or tires and ensure they are properly balanced. Uneven tire wear could also indicate other suspension or alignment issues.
* Wheel Bearings: Worn wheel bearings can cause vibrations, but usually more localized to a single wheel and axle. While it's *possible* for both front and rear bearings to fail simultaneously, it's less probable than the drivetrain causes listed above.
Troubleshooting Steps:
1. Check Fluid Levels: Start by checking the levels and condition of your transmission fluid, differential fluids (front and rear), and transfer case fluid (if applicable). Low or dirty fluid can indicate a problem.
2. Listen for Noises: Pay close attention to any unusual noises while driving, such as whining, groaning, clicking, or humming. These sounds can help pinpoint the source of the vibration.
3. Visual Inspection: Carefully inspect the driveshafts, U-joints, tires, and wheels for any visible damage.
4. Test Drive: Try accelerating slowly and then more aggressively to see if the vibration changes in intensity. This can help isolate when the problem occurs.
5. Professional Diagnosis: If you cannot identify the problem after these steps, it's best to take your vehicle to a qualified mechanic for a proper diagnosis. They have the tools and expertise to pinpoint the issue and perform the necessary repairs.
Ignoring the problem could lead to more serious and costly damage down the line. Get it checked out sooner rather than later.
