A transmission output shaft is the drive shaft that connects your vehicle’s gearbox to the axles and wheels. This mechanism is responsible for transferring power from the engine to these moving parts, so it must operate smoothly and reliably over time. Unfortunately, some transmission output shafts can fail, resulting in significant damage if they aren’t fixed quickly and correctly. If you’re experiencing transmission output shaft failure or know someone who is, here are four reasons why it might be happening.
Bad Bearings
While transmission output shafts typically last the life of your vehicle, they can occasionally fail. The most common issue with transmission output shaft failure is bad bearings that cause the output shaft to wobble. This will result in odd vibrations from the vehicle while driving and even strange noises. In addition, bad bearings can damage other components of the transmission. Fortunately, your mechanic can typically repair bearings before more damage occurs.
Leaking Fluid
Another common cause of output shaft failure is leaking transmission fluid. Without sufficient lubrication, the components of your transmission will overheat and eventually fail; the output shaft is no exception. If you notice a leaking transmission fluid, get it checked by a mechanic immediately.
The U-Joint Fails
On rear-wheel-drive vehicles, a failing universal joint can cause damage to the output shaft. If this is the case, you will notice vibrations while driving and loud noises while accelerating. Again, this is a severe issue that a professional should check out as soon as it’s seen.
The Seal is Worn
The rear seal of the transmission can wear out over time, allowing transmission fluid to leak out. When this occurs, the transmission components will lack proper lubrication, overheat, and become damaged. Leaking transmission fluid may trigger a warning code that will also make the check engine light come on. While the check engine light does not necessarily indicate an issue with the transmission, it does need to be diagnosed by a trusted mechanic. It’s best to get the rear seal replaced before severe damage occurs.
Issues with the transmission output shaft are rare, but they can occasionally happen. Typically, failure of some other component can cause problems with the transmission output shaft. If you notice transmission problems, it’s best to consult your auto care professional as soon as possible to avoid severe damage and a hefty repair bill.