Automatic Transmission Problems: 10 points to Know
The automatic transmission is a complex device. Despite advances in technology, problems with automatic transmissions are still common in many cars. The transmission is also expensive to repair or replace.
Here are several points to know about automatic transmission problems and ways to prevent or deal with them.
- If your car is still within powertrain warranty coverage, do any transmission-related services, such as fluid changes, at your dealership to keep your factory warranty valid.
If your vehicle is having a transmission problem soon after the factory warranty has expired, ask your dealer to apply for goodwill coverage or contact the manufacturer directly with the same request. In some, but not all, cases, the manufacturer may cover at least a portion of the repair outside of the warranty.
You can find the details of your warranty coverage in the Warranty Brochure that usually comes together with the Owner's Manual.
- If you are buying a used car or truck, watch out for signs of transmission problems during a test drive. Read more below.
Watch out for signs indicating that the vehicle has been used for towing a heavy trailer. In this case, the transmission is also more likely to be worn out. For example, an excessively worn-out trailer hitch and sagging rear springs are signs of heavy use.
- When buying a used vehicle, consider buying an extended Powertrain Warranty that will cover potential engine or transmission repairs. We know many people who have had their transmission repairs paid for by the extended warranty.
Study the warranty contract carefully: Does it have a claim limit (e.g., $1,000 per claim) or will it cover the full cost of repair? What is the coverage time period and mileage? Does it require regular maintenance receipts? Do you have to call the extended warranty before the repairs for authorization?
- Change the transmission fluid in regular intervals using the recommended fluid. Your dealer is the best place to get the transmission fluid changes done as they have the right fluid and they know how to get it done right.
In some vehicles, the transmission filter needs to be changed every time with the fluid change.
Read more: When you should or shouldn't change your automatic transmission fluid.
- Watch out for transmission fluid leaks (e.g., from cooler lines, a transmission pan, axle seals or extension housing), so that you can catch the leak early before a lack of fluid can cause problems. If you see drops of fluid or oil on your driveway, have your vehicle checked out.
- Consider installing an additional or upgraded transmission fluid cooler, especially if you plan on towing a trailer, as many transmission problems are caused by overheating. Keeping the transmission fluid cooler can prolong the life of the transmission.
- Check with the dealer or your mechanic if there is new software available for the transmission control module (TCM). Car makers often update TCM software to address some of the shifting concerns.
We know cases where all that is needed to fix some of the shifting issues is a procedure called 'transmission adaptive learning strategy' or 'initial learning'. This procedure helps TCM learn individual clutch characteristics. Do some research, Is there such a procedure for your vehicle Year Make and Model?
- If you feel that your transmission starts having some issues, have it checked out, as if the problem is caught early, the repair might be less costly.
One common example we see is when a lack of transmission fluid caused by a small leak first causes minor symptoms but later the transmission fails completely.
- If your transmission has failed, there are several repair options. The transmission can be rebuilt or replaced with a new, used or remanufactured unit. In either case, it's important to know what is the warranty on the repair? Consider both the cost of repairs and the length of the warranty provided by the repair facility.
- Often when a transmission has a known problem, many transmission shops offer upgrading your transmission with modified parts to make it last longer. If you are interested in something like this, check out YouTube, social media groups and forums dedicated to the Make, Year and Model of your vehicle. Ask your local transmission shop.
Signs of automatic transmission problems when test driving a used car
If the transmission has a dipstick, check the transmission fluid condition. If it looks very dirty or has a strong burnt smell, or shows presence of flakes or abrasive particles, avoid the vehicle.
If an AT warning light or some warning message about the transmission comes on while driving (e.g., Transmission Overheated), avoid the car.
Some transmission issues are more noticeable in the first few minutes after the vehicle is started, while the transmission is still cold. Other transmission flaws only become noticeable when the transmission is fully warmed up. This means that if possible, you may want to test drive the car or truck when it's still cold and continue until it's fully warmed up or take it for a second test drive when the vehicle is fully warmed up.
For example, when a vehicle with a worn-out transmission is started after sitting for a few hours or overnight, often the transmission will engage with a considerable delay: When shifting from Park to Drive, you will feel that the vehicle starts creeping forward only after a couple of seconds. Mechanics call it 'morning sickness'. Normally, the transmission should engage almost immediately when shifted into Drive. If there is a delay, avoid the vehicle as it's a sign of transmission wear.
During the test drive, watch out for any kind of shudder during acceleration, slipping, harsh shifting, delayed shifting, abnormal noises or jolts when coming to a stop. In some cars with a transmission problem you may feel that the vehicle shifts into neutral (loses power) while driving. In some trucks, transmission shudder may feel like driving over rumble strips.
Test drive in various modes: accelerating, decelerating, coasting, steady driving. When driving at a steady speed, watch out for engine RPMs fluctuating up and down. It's like the transmission is constantly hunting for the right gear. For example, this is one of the symptoms of a possible problem in a CVT (continuously variable) transmission. Normally the RPMs should be steady when driving at a constant speed.
Sometimes all forward gears work OK, but you may feel a strong clunk or a long delay when shifting into Reverse when parking the car. In this case, avoid the vehicle as it means the transmission is worn out. Normally, the Reverse should engage smoothly and almost immediately.
If anything feels wrong with the transmission, even if it seems to be a minor issue, avoid the vehicle. If in doubt, test drive another vehicle of the same Make Year and Model to compare.