Why does your truck bounce up and down while driving?

Answer 1

Bad shocks

they cause extra bounce in the ride, replace if necessary.

To Test:

How to Test Your Shocks By an eHow Contributor

Shocks are an important part of your car's safety system. If they are not operating properly, you are not only getting a bumpy ride, you are also endangering yourself and your passengers. Take the time to test your shocks every 15,000 miles. You can do these simple tests at home without any special tools.

Difficulty: Moderate

Instructions

1. Bounce your bumper. Put weight on a corner of the bumper or car. Move the car up and down to simulate a bump in the road. If the car bounces more than one and 1/2 times after you quit the bouncing, your shocks may be in need of replacement. Test all four shocks this way.

2. Check the tread on your tires. If the shocks are showing signs of wear, you can expect to see cupping or unusual wear on your tires as well.

3. Look at the shocks. There shouldn't be any signs of oil leakage around the seals. Neither should there be any dents or other signs of damage on the external surface of the shocks.

4. Examine the mountings for the shocks as well. Grab the shock and shake it to test if it is loose.

5. Pay attention as you drive your car. If the car seems harder to handle, it may be the shocks. If the steering wheel is vibrating a lot even on a smooth road surface, the shocks may need replacing. Worn shocks also can make the car feel like it is drifting as your turn corners.

6. Apply the brakes. The car's front end should not go down excessively if the shocks are in good shape.