Tire and Wheel Related:
* Tire imbalance: This is the most common cause. An imbalanced tire causes vibrations that increase with speed. This is easily diagnosed and fixed with a tire balancing.
* Tire wear: Uneven or excessive tire wear, including cupping or feathering, can lead to shaking. Inspect your tires for wear patterns. Worn tires should be replaced.
* Bent wheel: A bent rim or wheel will cause vibrations, especially at higher speeds. This requires wheel repair or replacement.
* Loose wheel: A wheel that isn't properly tightened can also cause shaking. Check the lug nuts to ensure they are properly torqued.
* Damaged tire: A bulge or other damage to the tire itself can cause shaking. Inspect your tires carefully.
Drivetrain Related:
* Driveshaft problems: A bent or damaged driveshaft can cause vibrations, particularly at higher speeds.
* U-joints: Worn or damaged universal joints (U-joints) in the driveshaft can cause shaking.
* Differential problems: Issues with the differential, such as worn bearings or gears, can lead to vibrations.
* Transmission problems: While less common, transmission problems can manifest as shaking, particularly if there's an internal issue.
Other Potential Causes:
* Suspension components: Worn suspension components like ball joints, tie rod ends, or control arm bushings can affect handling and cause shaking at higher speeds.
* Brakes: While less likely to cause shaking at *only* high speeds, warped brake rotors can contribute to vibrations, especially if you're braking.
* Engine misfire: A misfire can cause vibrations that might become more noticeable at higher speeds. This would usually be accompanied by other symptoms like rough idling or reduced power.
Troubleshooting Steps:
1. Start with the simplest: Check tire pressure, inspect tires for wear and damage, and make sure the wheels are properly tightened.
2. Get it professionally inspected: If the shaking persists, take your Tahoe to a qualified mechanic for a proper diagnosis. They have the tools and expertise to identify the root cause.
3. Describe the shaking: When you take it to the mechanic, be as descriptive as possible. Does it shake at a specific speed? Is it a constant shake, or does it pulsate? Does it shake in the steering wheel, the seat, or the whole vehicle? This will help them pinpoint the problem.
Don't ignore shaking at high speeds. It can indicate a serious problem that could affect your safety and lead to more expensive repairs if left unaddressed.
