8 Reasons an F150 Shakes & Shudders When Accelerating + Fixes


ford f150 shudders on acceleration

Some F150 owners may notice their truck shaking when accelerating. It can appear as a vibrating or shuddering sensation that becomes increasingly noticeable when you press on the gas pedal.

This is going to be very concerning for anybody, but the good news is that most of the time, if your ford f150 shudders on acceleration, you can fix it.

Why does my Ford F150 shake when accelerating?

There are several reasons that the shuddering could be including: 

  1. Wheels and alignment
  2. Motor mount
  3. Spark plugs
  4. Fuel injectors
  5. Transmission
  6. Vacuum hose
  7. Brake caliper

The first step is to remain calm and go through a checklist to rule things out bit by bit. Let’s start with the most common reasons and how to fix them.

Why an F150 shudders when accelerating

It may start as a simple issue that leads to a bigger problem if it is not fixed soon enough. The quicker you get to the source of the shaking and shuddering, the better. This is a common checklist that most mechanics and experienced truck owners use.

1. Wheels and alignment

One of the first things you should do is check and see if the tires are firmly attached to the wheels. Make sure they are balanced as well. A loose tire can cause shaking during acceleration and may lead to accidents if it is not fixed. 

Also don’t forget to check the lug nuts on the wheel. If they are not properly torqued down on the wheel, some could have become loose over time.

The wheel will have a wobbly feel to it and as your F150 accelerates and speeds up, the shaking and shuddering will become more violent.

How to fix it: 

  • Check for loose lug nuts and tighten.
  • If the shaking happens after new tires have been installed, then the unbalanced tires need to be fixed by a tire installer. They will mount the tire on a balancing machine to fix the error. They can also inspect the wheel.

2. Motor mount

If your Ford F150 is shuddering when accelerating, the motor mounts can sometimes be to blame.

Motor mounts are responsible for keeping the truck’s engine attached to the frame of the vehicle. They also isolate the surrounding engine parts from the shaking an engine makes, so passengers don’t feel the vibration of the engine when it’s running.

When the motor mounts are damaged or broken, the vibration of the engine is no longer contained. The shaking will become noticeable, and may become worse when accelerating, because the engine must work harder.

If you don’t get the motor mounts fixed, it may lead to other parts of the engine failing.

How to fix it: 

  • Assess wear and tear by checking the bolts that hold the mounts in place. Sometimes there may be one damaged motor mount, other times it may be all the mounts. Then, check the rubber that holds the two metal mounting points together. If the bolts are loose, tighten them. If the rubber is cracked or spongy, it may be time to replace it. A truck engine is large and may require a jack and blocks of wood in order to check for broken motor mounts or other signs of wear and tear. Another way to check is to watch for excessive movement around the motor mounts while a friend revs the engine.
  • You might need to replace the motor mounts. If there’s excessive shaking or clunking coming from under the hood while accelerating and the motor mounts seems damaged, it may be time to replace the motor mounts. Replacing the motor mounts can cost approximately $600 to $700 plus labor.

3. Spark plugs

If the motor mounts have no issues, then check your spark plugs next. The plugs are essential to keep your motor running smooth and prevent the engine from burning extra fuel. They are small metal pieces that are inserted into the engine to provide the spark needed to ignite the fuel. 

When spark plugs become worn or damaged it can lead to a misfire. It could also cause an increased vibration in the vehicle, particularly when your F150 accelerates.

Spark plugs should be to be inspected and changed periodically. usual recommendation is to change them every 30,000 miles.

How to fix it: 

  • Check spark plugs immediately. Take them out and check for deposits. If it looks black or dirty, it may need to be cleaned or replaced. Look at the plug wires and make sure they are not damaged either. As you inspect the spark plugs watch for an excessive spark plug gap, because it may cause the ignition coil to misfire and fail.
  • Install new spark plugs is a better idea. Some people prefer to try and clean the spark plugs to see if they still work, but it is advisable to replace them by purchasing new spark plugs. If you are unsure about which one to buy for your F150, check your manual or contact an auto shop.

While it may be cheaper to replace the spark plugs yourself, it usually requires experience and skill to do it right. Keep in mind, it may take several hours to complete.

Handy Hint: Have you heard about the Ford F250 death wobble?

4. Fuel injectors

Fuel injectors play an important role, they deliver necessary mixture of fuel and air to the engine. Over time they may become dirty. When the injectors are faulty or damaged it can affect the torque and cause your F150 to shake and shudder while accelerating. 

There are a few ways to determine if the fuel injectors are at fault for the shaking when accelerating. You can listen for certain clunking sounds and watch for any shaking when you press down on the gas pedal. Or, they can be tested with machines.

The engine has an internal diagnostic on board that can send a series of error codes to a reader. A technician can hook the engine up to a code reader, or you can purchase one. The codes will disclose if the fuel injectors, or any other part of the engine, are not performing correctly.

How to fix it: 

  • Clean your fuel injectors. In most cases, people prefer to have the dirty injectors cleaned. This will be a lot cheaper than replacing them. Cleaning injectors can cost around $50 to $80. If you want to try and clean the fuel injectors yourself, make sure you have the right equipment.
  • Replace Fuel injectors if the injectors cannot be cleaned or are damaged, then they may need to be replaced. Price estimates for F150 fuel injector replacement can be anywhere between $950 to $1,500 plus labor costs.

5. Damaged joints

If it is none of the above, then it’s time to check the axles and U-joints, because when they become damaged, your Ford F150 can shudder when accelerating.

Even if the driveshaft is nice and tight when you inspect it from under the truck, it may still be a good idea to take a closer look at the U-joints at the end of the axle points.

If the driveshaft and U-joints look fine. Double check the axles. There are usually two axles that connect the front wheels and back wheels to the truck. If they become bent or dented, it will cause vibration and shaking that increases in intensity as you accelerate.

Another way to check to see if the driveshaft, axle or U-joints are at fault is to watch for any vibration changes based on how heavy the load is. If the vibration increases or decreases with changes in the amount of load, then the axles and U-joints are affected. If it does not change, then it may be engine related.

How to fix it: 

  • Inspect U-Joints and axles; a visual inspection might not be enough! You may need to remove the driveshaft and take a closer look at the U-joints. It’s important to check the greasiness between the U-joints and check to see if they are dry or worn. While you are checking the joints, inspect the axles closely and look for any dents or bends that may cause issues. Take note of any wobbling with the steering wheel, because this can be another indicator of a bent axle.
  • Replace joints by removing the bolts and nuts from the end of the drive shaft, then remove the shaft itself. The joints will remain attached to the drive shaft. Spray WD-40 on the joints at the end.
  • After you have removed the U-joints, clean up the ends until they are nice and shiny. Then, install the new joints. You should see an improvement in shaking after the joints are replaced. If a mechanic does it in a shop it may cost anywhere between $300 to $500 plus labor.

6. Transmission

The transmission is a vital part of your F150’s engine, it changes the gears and transfers the engine’s power to the wheels. There are two different kinds of transmissions: automatic and manual. Automatic transmissions do the work on their own, while manual transmissions rely on the driver.

If there are any problems with the transmission it may lead to your F150 shaking during acceleration and other engine issues.

If the truck is revving higher than it normally does at lower speeds, this is a major warning sign. You may also hear a loud sound while accelerating. If this occurs, it may be time to take a look at the transmission.

How to fix it:

  • Check and replace fluids. Transmission fluid is vital for it to run smoothly and effectively. A dirty tranny fluid may cause issues. Check the fluid and take note of the color. If it’s pink, it’s probably still good. If it’s brown, then it’s time for a change: To change the fluids, drop the pan and change the filter. When the pan is off, look for any clogged lines and remove the clogs if there are any. Clean off any metals on the magnet in the pan. If there’s large chunks of metal, then that means something has broken inside the body of the transmission.
  • Don’t forget to fill it up with fresh fluid. Check the truck manual for the correct type of fluid if you’re unsure or ask your local auto shop.
  • Check transmission. You might need a technician who can hook the code reader to the engine and run diagnostics to see if there is a problem with the transmission. Or, you could have a mechanic look at the parts and test the transmission.
  • Replace parts/transmission if specific parts of the transmission are at fault. It might be cheaper to replace certain parts rather than buying a whole new transmission. If the entire transmission is affected, then it’s best to buy and install a new transmission. The cost of replacing a transmission can be approximately $2,000 to $3,000 plus labor.

If you wish to replace the transmission yourself, make sure you have the right equipment to properly lift the transmission safely out of the truck without it falling or sliding. Since transmissions can be complicated it would be ideal to have a technician on hand to help you with this task.

7. Vacuum hose

The F150 engine creates a vacuum when it’s running. The vacuum must be carefully controlled with several hoses in order for the engine to run smoothly. A torn or disconnected vacuum hose can cause an air leak which leads to various sensors getting confused, this may cause misfires and backfires. 

Keep in mind that if there is a misfire that is confusing the sensors, a code reader can be used to help pinpoint the source.

How to fix it: 

  • Check the hoses to make sure they are connected with no tears or cracks in them.
  • Remove the damaged hose and install news ones. Replacing with stronger silicone hoses is commonly done as a solution.

8. Brake caliper

The brake caliper holds the brake pads and pushes them against the rotor to make the vehicle stop. If there’s any issues with any of the calipers it may cause issues with the truck stopping properly.

Although rare, a stuck brake caliper can cause a Ford F150 to shudder when accelerating to speeds of 40 to 50 mph, and it may worsen as you get faster.

The steering wheel may also shake, especially when braking. Another sign that it’s the brake caliper is a burning odor when the truck comes to a stop.

How to fix it: 

  • Check the brake caliper by removing the tire and wheel and then inspecting the brake caliper.
  • If the brake caliper needs to be replaced then you will need to remove the faulty pads and caliper. It’s preferable to replace the pads when you replace the caliper.
  • Putting used pads back on the truck may cause the caliper to seize again. If you prefer to have a mechanic do it for you it may cost anywhere between $700 to $1500 plus labor.

Why an F150 shakes when braking

If you notice that your steering wheel or the entire F150 is shaking more while you press on the brake it may be caused by:

  • Brake rotors: Worn brake pads will make the vehicle shake as it touches the rotors. The pads may also stick to the caliper and cause shaking. The brake system will need to be inspected and possibly replaced to address the issue.
  • Guide pin failure: The brake calipers have guide pins to help them move freely. When the guide pins fail, the brake pads make uneven contact with the rotors, which may also cause seized calipers. Check the guide pin and replace it if needed.
  • Wheel bearing: if the wheel bearing is problematic it may cause issues with steering and braking. Inspect all the wheels and replace them if needed.
  • Bad alignment: A bad alignment can affect the tires and cause issues when braking. Going to a shop and doing an alignment should fix this issue.
  • Suspension damage: When the suspension is damaged, it may be felt when braking. Inspect the suspension system under the truck and replace it if needed.

Why an F150 shakes when idling

If you notice that your F150 is shaking more when it’s idling, then it may be caused by:

  • EGR sensor sticking: When the EGR sensor is dirty or damaged it causes the EGR valve to stay open. The valve and sensor must be cleaned with a climtool or replaced to correct this concern.
  • Misfire: An engine misfire may lead to more engine vibration and shaking, especially during idling. Addressing the source of a misfire will remedy this issue.
  • Faulty or dirty plugs: If the spark plugs are dirty or worn, it may cause misfires which leads to shaking in the engine. New spark plugs will need to be installed.
  • Exhaust: If the muffler or exhaust system is damaged, or has a leak, there will be an increased vibration and shaking while idling. The muffler system may need to be replaced to fix this issue.

Conclusion

I hope this short guide has helped if your F150 shakes when accelerating. I’ve noted down the most common reasons why this could be the case, but for full transparency, it might be something else.

However, in most cases where a F150 shudders on acceleration, these 8 problems will usually be the root cause.

Josh Henderson

Hi I'm Josh and I'm a huge pickup enthusiast. I started this website in 2018 in order to share all my projects and custom mod tips that I've done with my own Ford F-150.

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