Axles

All about axles: Different types and signs that they’re going bad

In Vehicle Maintenance by HomeTowne Auto Repair & Tire

In our daily rush with work, errands and family activities, we heavily rely on our vehicles.

Axles play the important role of making sure that the wheels keep turning. These parts connect the wheels and bear a car’s weight.

A few kinds of axles are found on automobiles today. 

CV Axles

Constant-Velocity Axles, or CV Axles, are found on most front wheel drive vehicles and can be used on four wheel drive cars. 

Four wheel drive trucks with CV Axles typically have them on the front wheels due to independent suspension. 

Some vehicles, like Subarus, have all wheel drive and CV Axles on four corners because they have independent suspension on the front and rear.

Certain trucks use CV Axles up front and Solid Axles in the back.

CV Axles have CV joints, which enable the transmission to run the front wheels evenly.

Straight Axles

Straight axles used to be used all the time. Now, they are usually on heavier duty trucks.

A rear differential is normally a straight axle.

They feature a simple setup and can be found on various types of suspension. 

You may see this kind of axle on the front of work vehicles.

It’s also popular among lifted trucks and Jeeps, especially if their owners go offroading. Some Jeeps have u-joints up front with four wheel drive, which allow the wheels to turn.

Rear Axles

Rear axles are made up of axle shafts that are connected through the differential. Different types of rear axles are produced, such as semi-floating and full-floating axles.

A Semi-floating axle links the wheel and the flange. Cars, SUVs and light trucks use this type.

Heavy duty trucks or some that are mid-size or have four-wheel drive require a full-floating axle, which is able to “float” due to the support of two bearings.

Signs of a bad axle

Your mechanic or the auto repair shop you bring your car to should be able to tell when your axle is going bad.

The technicians at HomeTowne recently let me know when I brought my Volkswagen in for another service that we will need to keep an eye on one of my axles.

There are also some symptoms to be watchful for.

Clicking: As an axle goes bad, you might notice a clicking sound as you turn or speed up.

Grease: Grease on the edge of a tire can be another indicator that the axle needs to be replaced. This can begin to leak if a boot is torn.

Vibrating: Axle problems could cause a vehicle’s steering wheel to start shaking (so much so that you can’t ignore it).

Leaking axle seals: If the bearings on a Solid Axle start going bad, they can start to put grooves in the axle shafts. If your axle seals are leaking, you definitely want to have that addressed. If the bearings wear out due to a lack of lubrication or water gets in there, then it can cause premature wear and do more damage than just the bearings. 

Squeaking u-joints: If the u-joints are squeaking or making noises, that can be an indicator that the u-joints on the Straight Axles are bad. 

Other maintenance

Depending on the type of vehicle you have and whether it uses four-wheel drive, there are u-joints that you need to keep greased and check to make sure they aren’t wearing out or experiencing play. 

If your car or truck has CV Axles, you should have the boots looked over during an oil change.

The owners of vehicles with solid axles should also ensure that the vent cap is functioning.

A lot of the time solid axles have a tube that runs from the differential to the body and a vent cap. Due to everyday use, heat and bugs, the vent cap may stop working correctly. As it heats up, lubrication could be pushed out of the seals.

For straight axles, you want to make sure that the correct type of differential fluid is used. Also, some of them need a limited slip additive and it’s important to confirm that it’s in there. Otherwise, you could cause problems just by servicing the differential.

Why you should have them replaced

Although you don’t need to have a bad axle replaced immediately, it’s a good idea to have a new one installed soon.

Choosing to put it off will cause the problem to become worse overtime.

The issue could also impact other components. For example, brakes may not work the way they should if grease leaks on them. 

If CV Axles are bad and causing problems, such as lots of clicking or you’re feeling shaking in the steering wheel, that could put extra wear on the bearings that are going into the transmission.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.