1. Tires and Wheels:
* Balance: This is the most common cause. Unbalanced tires or wheels will cause vibrations, especially at higher speeds. Get your tires and wheels professionally balanced.
* Rotation: Uneven tire wear can lead to vibrations. Rotate your tires according to the manufacturer's recommendations.
* Condition: Check tires for uneven wear, bulges, or damage. Replace worn or damaged tires. Also inspect the wheels for any bends or damage.
* Tire Pressure: Incorrect tire pressure can contribute to vibrations. Check and inflate your tires to the recommended pressure (found on a sticker inside the driver's side doorjamb or in your owner's manual).
2. Drivetrain:
* Driveshaft: A worn or unbalanced driveshaft is a possibility. This requires a professional inspection.
* U-Joints: Worn universal joints (U-joints) in the driveshaft can cause vibrations. A mechanic can diagnose this.
* Transmission: Problems within the transmission, while less likely to cause a vibration specifically at 70 mph, can't be ruled out. A transmission fluid change and inspection might be warranted.
* Axles: CV joints in the axles can wear out and cause vibrations.
3. Suspension:
* Wheel Bearings: Worn wheel bearings can create vibrations. A mechanic can check for play in the bearings.
* Control Arms/Bushings: Worn control arm bushings or other suspension components can affect handling and cause vibrations.
* Other Suspension Parts: Inspect other suspension components for wear or damage.
4. Brakes:
* Warped Rotors: Warped brake rotors can cause vibrations, especially when braking, but sometimes even at speed.
Troubleshooting Steps:
1. Start with the simplest and cheapest: Check tire pressure, rotate tires, and have them balanced. This is often the solution.
2. Visual Inspection: Carefully inspect your tires, wheels, and suspension components for any obvious signs of damage or wear.
3. Professional Inspection: If the problem persists after addressing the easy fixes, take your GP to a qualified mechanic for a thorough diagnosis. They have the tools and expertise to identify the root cause.
Important Note: Ignoring a vibration can lead to more serious and expensive problems. Addressing the issue promptly is advisable for safety and to prevent further damage.
