Ford F150 Humming Noise While Driving (During Accelerating and Slowind Down)
Ford F150 Humming noise while driving is one of the most common problems that people face when they drive at a speed ranging between 30 and 50 mph. If you have a Ford F150 truck and are experiencing humming noises while driving, this article will help you figure out what the problem might be. I will show you how to locate and fix this noise in your Ford F150 so that you don’t have to worry about the noise anymore.
So, why is Ford f150 making a whining or humming noise when accelerating at particular speeds? The most common cause of humming, whining or squeaking noise from Ford F150 while driving is a bad wheel bearing. The noise is caused when the bad bearing causes the tire and wheel to wobble or shake. You will hear a knocking sound, some vibrations, or a squeaking noise from the steering wheel or when turning in one direction. After replacing, you can drive your vehicle to check if it is fixed. If Ford F150 is still humming, it is probably a tire problem. You need to change the tires. If your Ford F150 is a 4WD, the most possible cause of humming noise in Ford150 with 4WD (four-wheel drive) could be a vacuum leak in the IWE system of Ford, due to which vacuum hubs are not fully disengaged. In such a situation, when you put your Ford F150 4WD in 4WD, it will stop producing a humming noise while driving in a straight line.
Bonus Read: Low oil pressure in engine at idle
Table of Contents
Causes of Humming Noise from Ford F150
Here are the causes of the humming noise from the Ford F150.
1. Bad U-joint
One of the most common reasons for humming noise from Ford 150 when accelerating is the bad U-joint. U-joint is usually used in 2WD trucks. If you hear a humming noise from the rear of your Ford vehicle while driving above 30 or 40mph, there can be faults in the axle of your Ford F150. U-joint can be one of them.
U-joint is also called a universal joint that helps maintain the alignment between the driving and drive shafts of a vehicle. If there is rust on the u-joint, the yokes (connecting points of the joint) will not properly work, due to which vibrations can be produced in the shaft. This will cause whining, humming, or squeaking noise in the F150 vehicle. A bad U-joint usually produces a clunking or squeaking sound.
Check out the below video to see how bad U-joint in F150 looks like:
Replacing universal joints is cheaper compared to the other components of the axle of F150. So, I highly recommend you always first check the universal joint of your Ford f150 vehicle.
2. Worn-out Transmission Fluid or Differential Oil
Worn-out transmission fluid produces a noise similar to rumble strips when Ford F150 is under acceleration. The transmission fluid is different from the motor oil. Both oils have different containers in the engine. The function of transmission fluid is to ensure the various parts of the transmission system such as the torque converter, transfer case, and slip joints.
Differential oil lubricates the differential system of the vehicle. If there is a low level of differential oil, or it is leaking through the differential cover, pinion gears in differential housing will create a whining sound in Ford F150. You have to take help from the owner’s manual to find the location where transmission fluid and differential oil are inserted.
You can check out the below video in which a guy is refilling differential oil in F150.
3. Wheel Bearing Is Damaged
Wheel bearing is used to rotate the wheels of a vehicle. They help in keeping the wheel turning smoothly. The bearing consists of two cups (inner race and outer race), a series of balls, and a retainer. The ball is the part where the axle of the wheel rotates.
At the center of a vehicle’s wheels, there are hollow pieces of metals called “hubs”. Wheel bearings fit tightly within those hubs and run on the metal axle shaft of the Ford F150, which then helps to reduce friction when wheels spin. A faulty wheel bearing can lead to a number of problems like vibration, noise, steering problems, and tire wear.
If your Ford F150 is producing a humming or squealing noise while turning, there are the chances that wheel bearing is damaged. Due to the difference in vehicle loading when turning left or right, opposite forces are placed on the bearing, causing a loud noise when only turning one way.
To verify whether a wheel bearing of F150 is damaged or not, swerve slightly from left to right and see if the sound of humming changes its pitch. If it does, the bearings of the wheel are damaged.
If you’re wondering why do wheel bearings of the Ford F150 fail, there are certain reasons. These include unbalanced tires, riding the vehicle on uneven terrains, or driving through potholes.
The weight of a vehicle rests on the wheel bearings. Uneven radial forces are exerted on the wheel bearing when the Ford truck is driven on uneven roads. When wheel bearing is subjected to these high stresses, it eventually fails which will cause humming noise in the F150 vehicle.
You can test the bad wheel bearing of your Ford F150 by lifting the truck with both wheels off the ground and lowering either the right or left wheel onto a big piece of cinderblock or driftwood. This way you have one wheel off of the ground.
Run the car in 1st and 2nd gear and see if you hear the noise with the wheel that is off the ground. Do the same to the other wheel. Do the same with the other wheel. If you do not hear any noise from the wheels, it means the tire of the Ford F150 is bad.
Replacing a wheel bearing is quite an expensive job. It would take over $1500 to replace the wheel bearing.
4. Uneven Tires Wear
If the wheel bearing is fine, but you are hearing a humming sound in Ford F150, the chances are that the tires of the F150 have gone bad. Humming sound in F150 is usually caused when the tires are worn out unevenly. If notice that a tire of your F150 is wearing out faster on the outside edges, then your tire is most likely underinflated. If it is showing more wear in the center, then it is most likely overinflated.
Here is how a tire looks with overinflation and underinflation.
Tires also wear unevenly due to the misalignment of the wheel. If the tire is wearing faster on one edge, it means that the wheel is not properly aligned. Some other ways through which you can tell whether your truck needs an alignment or not is when your F150 vehicle seems to drift to one side, even when you should be driving straight or if you are driving straight, but your steering wheel is not centered.
5. Faulty CV Joint
If your Ford F150 truck is a four-wheel drive and it is producing annoying humming noise, there are the chances that the CV (constant velocity) joint is failed. Like a u-joint, the CV joint is used in the 4wd or front-wheel drive vehicles.
CV joints are similar to universal joints, except that they have an extra ball spline that allows them to transmit torque while keeping both wheels at the same speed. In a CV joint, the ends of two round shafts are connected by a flexible rubber boot called a CV boot. The boot of the CV joint is packed with grease.
The function of a CV joint is to transfer torque from transfer to the front wheels at constant rotational velocity when the wheels are taking a turn. CV joint maintains the constant velocity of the front wheels by accommodating the up-and-down motion of the suspension.
This is how a CV joint is found in vehicles.
Here is a video demo of the working of a CV joint:
Now, the most common problem with the CV joint is that when a protective rubber boot is cracked due to the shock loading, the grease is leaked out of the CV joint. When the rubber boot of the CV joint is torn, it can also be filled with dirt and debris. This causes the ball bearing in the CV joint to wear faster and eventually fail.
If the humming noise is coming from the front axle or steering wheel of your vehicle, it means that the CV joint is damaged. In case of a broken CV joint, you will hear a clicking or popping noise which will intensify while taking a tight turn or accelerating when in 4WD mode. If the CV joint is damaged, you can also feel that the vehicle is bouncing while driving on a flat paved road. Moreover, the grease can also be seen on the edges of a tire.
If you notice the above symptoms, you should instantly look at whether a boot of a CV joint is broken or the rollers inside the casing of the CV joint are also worn. If you catch this problem at the early stages, there are chances that you only need to replace the rubber boot of the CV joint.
The cost of replacing the CV joint depends on its condition and the hourly rate of your mechanic. If only the rubber boot is cracked, the job of fixing the CV joint can be done for around $200. If the whole CV axle/shaft needs to be replaced, the cost can range from $500 to over $1000.
6. Bad Pinion Bearing/Gear
A bad pinion bearing or the gear which is mounted on that bearing can be the cause of a humming noise in Ford F150. Pinion gears are the smallest gears in the differential that are meshed with each other.
The pinion bearing is mounted behind the pinion gear so that the forces (load) exerted on the shaft when gears mesh with each other, are balanced by the pinion bearing.
If the pinion bearing is damaged, it will not be able to bear the load exerted on the pinion shaft by the pinion gears. As a result, the pinion shaft will vibrate and cause a humming sound in the Ford F150.
In the picture below, you can see three small gears. These are called pinion gears.
And here is how pinion gear and pinion bearing are mounted on a shaft.
Pinion gears are found in the differential housing of the vehicle. The method to diagnose whether the pinion bearing is damaged or not is done by following steps:
- First, swerve the truck right or left. If the sound or pitch of the hum doesn’t change, the damaged pinion bearing is most likely causing a humming noise in Ford F150.
- Now, put your Ford F150 in neutral, and see if the pitch of the hum changes. If it does, it’s probably the pre-load on the pinion bearings making noise in Ford F150.
Pinion gear can also crack if the pinion bearing is damaged. When the teeth of the gear are damaged, they can’t properly mesh with the other gears as there has to be a certain clearance between the teeth of meshed gears for smooth operation. If the clearance between gear teeth due to the crack increases, it can also produce humming or grown noise in Ford F150.
7. Bad IWE Actuator System
Integrated Wheel End (IWE) system is what unlocks and locks the front hubs when you change back and forth from 2WD and 4WD and vice versa. IWE actuator system entirely depends on the IWE solenoid, vacuum hub (actuator), and IWE check valve. IWE solenoid and check valve are located by the master brake cylinder.
A bad IWE (Integrated Wheel End) valve can cause a humming sound in those Ford F150 trucks that are 4WD. A lot of times if the IWE solenoid starts leaking vacuum, it’ll cause noise at low speed that goes away when you get on the throttle as the vacuum grows.
If you want an in-depth understanding of the IWE actuator system in Ford F150, the person has written a great guide in this forum.
The best way to check whether you have a problem with the IWE actuator system is to shift your vehicle to 4WD. If the humming sound goes away, it means the IWE actuator system is faulty. Another way is to unplug the vacuum line from your IWE solenoid to the actuators and see if the noise goes away.
To find the vacuum line of the IWE actuator system, you can take help from the vacuum line diagram in the owner’s manual of your Ford F150 truck.
You should take help from a mechanic to diagnose the IWE system as it is a pretty complex task. You will not be handle it yourself. To diagnose the IWE system, you will need a vacuum pump with a gauge on it. You can get this from amazon.
You can check out the below video for troubleshooting the IWE solenoid system.
Final Thoughts About Humming Noise From Ford F150
So, I have tried my best to pinpoint the most possible causes of Ford F150 humming noise while driving which include:
- Bad wheel bearing
- Faulty IWE solenoid and actuator
- Uneven tire wear
- bad CV and U-joint
- Damaged pinion gear
I hope after checking the above-mentioned components of the transmission system, the humming noise in your Ford F150 will go away.