Even if you aren’t a gearhead, you probably know that your vehicle’s transmission is a big deal. Transmissions are crucial for transferring power from your engine to the wheels. Most of today’s transmissions are automatic — designed to shift on their own based on a vehicle’s speed.
Automatic transmissions do their job without issue most of the time, but they are notoriously complex. A common issue with automatic transmissions, especially as they age, is slipping. This can be felt when you step on the gas and the engine revs, but your vehicle doesn’t move accordingly. You might feel that your car isn’t moving through the gears normally, or is having trouble staying in gear.
WHY SLIPS HAPPEN
Automatic transmissions have many moving parts, which means that there are several ways they can malfunction, break down, or accumulate wear and tear. Thankfully, most problems can be caught and fixed before you have a total transmission failure, which can leave you with a costly bill to repair or replace the unit. Let’s take a look at the most common causes of a slipping transmission.
Transmission fluid
Like engine oil, transmission fluid is extremely important; without it, or the right amount of it, your transmission won’t work properly. Fluid issues are the cause of, or at least involved in, most of the problems you could have with a transmission, including those listed here. A few things to look for with fluid specifically:
For starters, your transmission fluid could simply be low. If your vehicle has a dipstick for transmission fluid (not all do), you can check the level yourself. Your engine should be warmed up and your car should be on a level surface and running to do this. If it’s low, top it off, but do not overfill it. If you don’t have a dipstick and your transmission has slipped or you’re experiencing other transmission-related issues (burning smell, grinding noises, hesitation to shift etc.), take your vehicle to a professional technician.
Like engine oil, your vehicle has recommendations for how often to replace the transmission fluid. With each mile you drive, your transmission fluid works to keep your transmission cool and clean, and it can start to get gunky or become debris-filled when you approach the recommended time frame for replacement.
You might also have a transmission fluid leak. Transmission fluid is a distinct red color. If you find fluid under your vehicle, you may have a bad gasket or connection somewhere. It’s best to take it to a professional to get it addressed. Do not attempt to drive your car if it has a significant transmission fluid leak, as severe damage could result.
Transmission bands
In automatic transmissions, bands are what hold and link the gears together. Just like anything else in your engine, over time, transmission bands can wear down or even break. If your transmission bands are in rough shape, you’ll notice that your vehicle can’t shift properly.
Worn out gears
Your vehicle’s gears take a beating and are designed with that in mind. They are built to last a long time, but they do wear out in older vehicles due to high mileage, excessive heat, or from low transmission fluid. If this is the case in your vehicle, you’ll notice a rough transition or grinding noises when you switch gears.
Clutch problems
We usually think of clutches when talking about manual transmissions, but automatic transmissions have a clutch system, too. Clutch packs consist of multiple plates sandwiched together. Again, if fluid levels are not maintained, these plates can wear out.
Malfunctioning solenoid
Your transmission’s solenoid is responsible for regulating the amount of fluid circulating in the transmission — it pushes fluid into the valve body to engage the proper gear. Suspect the solenoid if you’re experiencing transmission problems and don’t have a leak.
MAINTENANCE
The key to keeping up your automatic transmission is, you guessed it, maintaining proper fluid levels and changing fluid when recommended by your vehicle’s manufacturer. If you’re changing fluid on your own, keep in mind that there are several types of transmission fluid. You should only use the type specified by the manufacturer.
