Why Does My Pickup Truck Shake When I Accelerate?

Owning a truck has a lot of perks, and for some people, having their own pickup truck might be the culmination of a lifelong dream. Trucks can be pricier than cars, but their toughness and versatility make them one of the most popular vehicles in the United States. If your beloved truck has begun to shudder whenever you press the gas, you might be wondering why?

A truck might shake during acceleration for a number of reasons, including: damaged motor mount, unbalanced tires, seized brake calipers, and even a bent drive shaft. 

The love that some owners have for their trucks can make even the smallest mechanical problem seem like a nightmare, and this includes vibrations and rattling while driving.

These problems range greatly in severity and difficulty to fix, so it’s important that if your truck rattles that you find out the culprit for the shakes as soon as possible. In this article, we’ll go more in depth into why your truck might be rattling when you accelerate.

Why Does My Truck Shake When I Hit The Gas Pedal?

There are a number of reasons your truck may shake when accelerating, so unless the cause of the problem is obvious, you might have to check quite a few things before landing on what the real root of the problem is.

Some of the most common reasons a truck might shake during acceleration are: 

• Unbalanced Tires
• Loose wheel nuts 
• Damaged motor mount 
• Seized brake calipers 
• Bent drive shaft

Let’s look a little closer at each of these truck-shaking issues and what needs to be done to solve them.

Unbalanced Tires

If your truck begins to shudder at speeds ranging from 50 to 65 miles per hour, there is a good chance that unbalanced tires are to blame, especially if you’ve recently gotten new tires or had one replaced.

It might surprise you to know that tires aren’t perfectly shaped all around. Once there is some wear on the tire tread, all four tires will change shape to best distribute the weight of the truck on the road.

If something has caused these tires to gain wear on the tire tread at different times, or if the wear is more concentrated on one or two tires and not all 4, then the tires are considered unbalanced. This means they won’t sit flat on the road like we expect our tires to.

Once you reach speeds of about 50 miles per hour on unbalanced tires, the fault in the weight distribution of the tires will cause shaking of the entire vehicle. If this is the case, it’s a simple fix; just have your tires balanced and all will be back to normal!

Loose Wheel Nuts

Wheel nuts, also known as lug nuts, are the nuts that hold your tire onto your car. If one of these nuts is loose, it’s not only a dangerous situation, but it can also cause your truck to shake violently.

The shaking will be most apparent during the acceleration, as the higher speeds will cause the wheel to shake even more because of the loose nut.

Damaged Motor Mount

The most integral part to any truck is the motor, and this all important component is attached to the frame of the truck by the motor mount. If the motor mount is damaged, the truck motor will shake inside the frame when you accelerate, causing the entire vehicle to shudder.

Seized Brake Calipers

One part of the brakes on a truck that can cause shaking is the caliper. If a brake caliper is seized, it will always be in contact with the tire itself, not just when you hit the brakes.

The caliper applying pressure to the tire can cause vibrations that get more intense the faster the truck accelerates.

Bent Drive Shaft

A bent drive shaft will usually only cause shaking or vibration in a rear-wheel drive truck. The drive shaft turns the back wheels and is powered by the truck’s transmission. If this shaft is damaged in any way, when it rotates, the truck will shake.

The faster the shaft turns, the harder the truck will shake, which is why acceleration exacerbates the problem.

What Would Cause a Truck to Shake When Accelerating?

Besides the aforementioned reasons, there are a few other things that might cause a truck to shake when it’s accelerating.

One likely culprit for chronic shaking are burnt out spark plugs! When all your truck’s spark plugs are in good shape, acceleration will be smooth and easy, but if any are worn out, acceleration may be slow and arduous.

Luckily, like unbalanced tires, worn out spark plugs are an easy and relatively inexpensive fix compared to some of the other truck-shaking issues.

Truck Shakes When Accelerating but Not When Coasting

A truck that shakes when accelerating but not when coasting might seem like a confusing problem to fix, but in reality, this behavior can help you narrow down the problem with your rattling truck.

Only a few issues will cause vibrations during acceleration but not when coasting. One of the most common reasons for this problem is worn out or damaged motor mounts. When your truck is accelerating, the engine is moving and shaking a lot more than when the truck is coasting.

Since undamaged motor mounts keep your truck’s ride smooth but holding the motor in place and absorbing vibrations, a damaged one will allow those vibrations to shake the whole truck. Acceleration makes the motor vibrate, but coasting does not.

In Conclusion

At the end of the day, the reasons for a pickup truck shaking when accelerating are much more numerous than we would like. It can take some serious examination or even require a professional to diagnose the problem, but once you know what is plaguing your truck, you can be on the way to fixing it.

A shaking truck body shouldn’t be ignored, for your safety and for the longevity of your truck, so if you’re noticing a vibration when hitting the gas, it might be time to slow down and do some diagnosing.