Ford F-150 has a vacuum-operated hub instead of an electronic and automatic one. The vacuum-operated hubs allow the engagement and disengagement of four-wheel drive. It is helpful to connect and disconnect the wheels from the axle. These are helpful in the engagement of four-wheel and two-wheel drive.
Ford F150 vacuum hub problems include chipped teeth of the hub, worn-out seals, vacuum leaks, worn-out internal parts, damaged vacuum hub actuator, grinding noise, poor engagement of four-wheel drive, and partial gear shifting.
I was driving my Ford F150 on the highway on winter days, and suddenly, heavy snow started. I tried to engage the 4WD system to provide traction to the tires and decrease their locking and skidding chances on slippery surfaces. Check 4WD illuminated on the screen, which showed the issue in the engagement of the four-wheel drive system.
I became worried because of the stormy weather. It was not safe for me to drive on a snowy road, but I continued driving at slow speed and reached the dealership. They used the scanner devices to read the error codes and fix the issue.
| Problems | Solutions |
| Chipped teeth of hub | Avoid harsh driving on off-roads |
| Worn out seals | Replace worn-out seals |
| Vacuum leaks | Use high-quality silicone material hoses |
| Vibration | Replace the misaligned hub |
| Worn-out internal parts | Use a brush to remove contaminants |
| Grinding noise | Replace the vacuum hub actuator |
| Difficulty in shifting | Inspect oil leakage |
| Poor engagement of four-wheel drive | Check seals that surround the windshield |
Chipped teeth of vacuum hub
You cannot engage and disengage the 4WD system in your pickup truck because of the chipped and broken teeth of the vacuum hub. The part is connected to the wheel assembly and axles to lock and unlock the wheels according to the selected drive system.
These are vulnerable to wear and tear because of the excessive torque. I faced this problem after towing the heavy trailer with my Ford F150.
It was a luxurious trailer and equipped with a lot of amenities. I did not check its gross vehicle weight rating and towed it with my truck.
I realized that the 4WD system in my vehicle had stopped functioning, and I heard the rattling and ground noise when I pressed the button to engage the four-wheel drive.
I checked the wheel assembly and saw the broken tooth of the hub because of the heavy load of the trailer and excessive pressure on these components.
In addition, it can also break because of frequent trips to off-road areas. Hub assembly teeth can also break by hitting larger stones and potholes on uneven terrains.
You should avoid harsh driving on off-roads because it can increase the chances of damage to several components. Moreover, you have to replace the complete hub assembly to fix the broken tooth issue.
You can decrease the risk of breaking by properly maintaining their parts and protecting them from moisture exposure.
Worn out seals
Vacuum hub has seals in their surroundings to maintain the air pressure for engagement and disengagement of 2WD and 4WD. The broken seals do not allow the components to maintain enough pressure for locking and unlocking the wheels.
You can face difficulty shifting between the various driving modes because of insufficient vacuum pressure inside the seals. The seals are vulnerable to wear and tear because of their age.
Constant pressure changes increase the risk of premature wearing of vacuum seals. In addition, contaminants from the roads, including water, mud, and road salts, also cause their degradation.
Contaminated hubs can also damage these seals. Using seal protectors in your high-mileage pickup trucks is better to protect against road contaminants and corrosion.
However, you can also replace the worn-out seal with a new one to maintain the vacuum pressure.
Vacuum leaks
Vacuum hoses and lines supply sufficient pressure to the hub to engage and disengage the drive terrain components in the four-wheel driving system.
You cannot engage the 4WD system in your trucks because of the vacuum leaks that cannot provide sufficient pressure to the hub assembly.
Vacuum leaks are common because of damaged hoses and lines. In addition, the issue also comes because of the loose and disconnected vacuum hoses.
Heat and moisture exposure increase the risk of cracking of vacuum lines. They become brittle because of the high temperature of the engines and are vulnerable to hairline cracks. Moreover, vibrations while driving on uneven roads lead to loose connections.
My neighbor also faced the same issue in his Ford F150 pickup truck because of the cracked vacuum lines. He told me he replaced the low-quality vacuum hoses with high-quality silicone material hoses that are resistant to heat, chemicals, and moisture exposure.
Vibrations
My friend had the 2017 Ford F150 a few years back. He was completely satisfied with it because of its mileage and off-roading capabilities.
He sold his pickup truck because he wanted to upgrade it with some of the latest models of luxurious brands. Once, he told me he faced the issue of excessive vibrations from the front side of his vehicle.
He checked the engine mounts, but those were fine and at their place. He used the pressure gauge to check the air pressure in the tires, but it was also normal.
He became worried and called the expert mechanic to inspect the problem. The mechanic checked the wheel assembly and found the bent and misaligned hub.
Damaged and misaligned hubs cannot maintain the smooth tire propelling, leading to vibrations. Replacing damaged or misaligned parts with new ones is better for a comfortable driving experience.
Worn-out internal parts
Vacuum hubs also stop functioning because of the damaged components of the internal assembly. These are vulnerable to failure because of contaminants on their surface.
Dirt, debris, corrosion mud, and road salts cause the degradation of their internal parts. In addition, these are vulnerable to physical damage because of road accidents and serious impacts.
I also saw the dust and corrosion near the hub assembly of my truck. I used the wire brush to remove the contaminants from their surface. I also painted their surface with anti-corrosive paints to decrease the risk of corrosion-related damage.
Grinding noise
Many people also complain that they hear the grinding noise from their Ford F150 when engaging the four-wheel drive on snowy and slippery roads to maintain traction.
Grinding noise comes because of poor alignment of hub assembly and damaged parts. In addition, the issue also comes when poorly lubricated vacuum hoses rub against each other.
You can also hear this noise because of the damaged vacuum hub actuator. It is better to call an expert mechanic to inspect the grinding noise. Replace the vacuum hub actuator to fix the grinding noise in your pickup truck.
Difficulty in shifting
Many people complain that they face issues while engaging the four-wheel and two-wheel drive systems in their Ford trucks according to the road conditions.
The issue comes because of clogged vacuum hoses and damaged lines that cannot provide sufficient pressure to the hub assembly.
Dust and debris because of frequent off-roading cause clogging of vacuum lines and disrupt the smooth flow of pressure. Moreover, oil leakage also causes clogging of these lines.
You can decrease the risk of clogging by inspecting the oil leaks in the engine compartment and fixing them in a timely to reduce the risk of damages.
Poor engagement of four-wheel drive
The vacuum hub works with an integrated wheel end system that uses the solenoid to activate the four-wheel drive system. You cannot engage the four-wheel drive in your trucks because of the damaged solenoid.
It can get damaged because of water exposure. The solenoid is located in the cowl area of the Ford F150, which is vulnerable to water exposure.
Poor windshield installation allows the rainwater and melting snow to seep inside and damage the electric components.
Moisture from the solenoid travels to the integrated wheel end and causes corrosion there. It is necessary to install the windshield correctly to decrease the moisture exposure.
You should also ensure that the seals surrounding the windshield are free from cracks and shrinking.
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