Signs of a Bad Transaxle

The word “transaxle” is a term that contains and explains its primary functions — a transmission and a driven axle. More precisely, a transaxle is a single mechanical unit that takes a transmission and combines it with a differential that transmits the power from the transmission to the wheels. There are automatic transaxles and manual transaxles, depending on the type of transmission used in the transaxle. The transaxle is connected to the engine at the transmission end, and to the driving wheels at the differential end.

Does your car have a transaxle?

There are many cars that have transaxles, so it is very likely that your car has one. Most cars with a transaxle have their engine and their driven wheels at the same end, but some do not. These include:

• Front-engine, front-wheel drive cars (plus those that offer all-wheel-drive)
• Rear-engine, rear-wheel drive cars (VW Old Beetle, Porsche 911)
• Mid-engine sports cars (Porsche Cayman/Boxster, Ferrari 488, Lamborghini Huracan)
• Front-engine, rear-wheel drive sports cars (Ferrari 812 Superfast, Mercedes AMG-GT, Chevrolet Corvette C5/6/7)

The first three types listed use a transaxle for improved packaging, since the engine is very close to the wheels that are being driven. The last category includes front-engine sports cars with rear-wheel drive that use a transaxle in the rear, for better weight distribution and improved performance.

What are the signs of a bad transaxle?

Because a transaxle combines the functions of a transmission and a differential, there can be quite a few different warning signs of a bad transaxle. Let’s see what they are:

• Unusual noises: You may hear strange noises coming from or near your transaxle. These can include whining, clunking, whistling, grinding, clicking, humming, growling, whirring, rattling or rumbling.

Depending on exactly where they are coming from, and under what circumstances they occur, your mechanic can determine whether they indicate an issue with your differential, your transmission, or a CV joint, which is usually found on the driveshaft between the transaxle and the wheel being driven.

• Abnormal shifting: If you are experiencing problems with the way that your car is shifting gears, this could indicate a serious problem with your transaxle. This can manifest itself in a variety of ways, including hard shifting, slipping gears or failure to shift.

If your car exhibits shifting problems like these, do not delay – call your mechanic right away and get your car into the repair shop for service.

• Your car will not move: In this extreme situation your car will be unable to move under its own power. You may notice that the car will not shift into any gear, or perhaps the engine will rev after you shift into gear, but power is not getting to the wheels. Your drive wheels may even lock up. If any of these things happen, call your mechanic and a tow truck, in that order. Your car is going to the repair shop to be fixed.

• You smell something burning: This could be an indication that your transaxle has overheated and damaged your transmission fluid. Look in your owner’s manual for directions on how to check your transmission fluid. If the fluid level is low or if it looks dark and smells burnt, call your mechanic for advice.

• You notice fluid leaks on the ground under your vehicle: The oil or fluid in your transaxle can look similar to oil, when it leaks out and ends up on the ground under your car. Try to check where the leaks are coming from – if it appears to be leaking from the area under your drive axles, this could indicate a transaxle problem. Call your mechanic and have this checked out right away.

Should you drive a car with a bad transaxle?

No. This is a major component of your drivetrain. Any problems should be addressed as soon as they appear, before they get worse and cause major damage that could strand you by the side of the road and be very expensive to fix. Remember, your transaxle contains both your transmission and your differential, two key parts responsible for getting your engine’s power to the wheels. Don’t put off any needed repairs, or you will probably regret it.

How do you fix a bad transaxle?

The correct fix for a bad transaxle depends on exactly what the problem is, and which internal parts are affected. Your bad transaxle could require anything from minor repairs to a major rebuild, or even a replacement if the damage is unusually severe.

Your mechanic will diagnose your bad transaxle’s problem by driving it (if it’s drivable), checking for any trouble codes in the powertrain computer, finding the source of any leaks, analyzing the condition of your transmission fluid or oil, and verifying your bad transaxle’s overall mechanical condition. This may involve removing and/or opening up your bad transaxle to see what’s going on inside. Repairs usually involve replacing any bad components with new ones, reassembling the transaxle, reinstalling it, and filling it with fresh fluid. The last step is a road test to verify that your transaxle is functioning properly.

Depending on your car’s age and mileage, your mechanic may recommend completely replacing your bad transaxle with a remanufactured transaxle. This will give you the benefit of a multi-year warranty on the replacement transaxle, including all the parts inside it. If your car is in the middle part of its lifespan and you plan to keep it a while, this is a sound, but expensive, option.

On the other hand, you may decide that your car is too old for such a large investment, or you plan to sell the car soon after it has been fixed. In this case, you might consider a used transaxle from an auto recycler. In exchange for an uncertain lifespan, you will save money. Discuss these options with your mechanic, who will help you make the best decision, based on your needs.

Can you replace a bad transaxle yourself?

Probably not. Unless you have experience in diagnosing and repairing this type of major mechanical system, this job is best left to a professional mechanic. Because your transaxle incorporates the transmission and the differential, it is a very heavy component, with hundreds of precisely assembled moving parts inside, all immersed in gear oil or transmission fluid. Any significant repairs to a bad transaxle will likely require it to be removed from the vehicle, a major job in itself. If you don’t know what you’re doing, you could cause additional damage, or even hurt yourself in the process. This is not a typical DIY project!

What you can do, to prevent most problems with your transaxle, is to regularly check your transmission/transaxle fluid or oil. Make sure it is kept topped up, and let your mechanic know immediately if it looks dark or smells burnt.