Help, My Transmission Is Slipping!

Most of you have probably have never felt the transmission slipping in your car. That’s a good thing. Slipping transmissions are indicative of something wrong, sometimes seriously wrong. In this article we will look at how to identify a slipping transmission and what usually has to be done to fix it.

What’s a slipping transmission feel like?

When you are driving a car, there is a more or less direct connection from your engine to the wheels. So, as your engine rotates, the transmission rotates, the differential rotates and then the wheels rotate. Although you aren’t likely thinking about the mechanics of all this rotating stuff, it has a certain feeling to it when you drive. For example, when you push the accelerator pedal, your car moves forward or backward, depending on the gear you are in. Need to move faster, like you are passing someone, mash the gas pedal and your car will quickly accelerate.

However, if you have a transmission that is slipping, it will have a very different feeling. When you apply the gas, you will hear the engine gain speed but the car won’t move as quickly in response. It will feel like its “slipping,” hence the phrase! In an extreme case, when you push the gas pedal, the car may not move at all. In a situation like this, you usually have something really wrong, like a “blown” transmission.

What causes slipping?

The reason that a transmission can slip will depend on the type of transmission you have in your vehicle. There are essentially three types of transmissions in today’s cars: automatic, standard (or “manual”), and CVT (or “continuously variable transmission”.)

Automatic Transmissions – If you have an automatic transmission and it slips while you are driving, according to our subject matter experts at Gainesville Dodge of Gainesville, a local Chrysler, Dodge, Jeep, Ram dealer in Gainesboro, FL, the most common cause is that your transmission fluid is low. The fluid in an automatic transmission is its lifeblood. Besides basic lubrication, the fluid is used in “hydraulic circuits” within the transmission using valves and pistons to change gears. If the fluid is low, the internal hydraulic systems won’t work well and the transmission will often begin to slip.

You can check the level of fluid in your transmission via the transmission dip stick. Sometimes these are hard to find, but your car definitely has one. (Consult your owner’s manual if you can’t find it.) Locate the dipstick, pull it out and wipe it, put it back in and then pull it out to see how much fluid is in there. (There will be marks on the stick that show you how much fluid is present.) If the level is low, add more fluid -just be careful to add the right fluid because not all automatic transmission fluid is the same! Definitely check your owner’s manual, or call your local dealer to find out what type of fluid to use.

The next question usually is: why is my fluid so low? Well, it’s probably because you have a leak. Automatic transmissions don’t “use up” the fluid in any way so the only reason that some will be missing is from a leak. The cause of the leak is probably a failure of one of the seals that keep the oil inside the transmission. It isn’t uncommon in an older vehicle.

And, unfortunately, your slipping automatic transmission could be due to a failure inside the transmission. This will usually mean the transmission needs to be rebuilt.

Manual Transmissions – A standard (“manual”) transmission uses fluid too, but leaks aren’t a common issue. If you have a manual and it’s slipping, the problem is usually the clutch. The clutch is a special plate coated with a friction material (similar to brake pads) that is situated next to the engine’s flywheel. Over time, the friction material will wear away and you will experience the same slipping feeling that an automatic transmission develops. You may even smell that “burning paper” smell that comes from overheated brakes too.

Note: “Riding your clutch”—that is, leaving your foot on the clutch pedal when you aren’t using it—will wear out a clutch disc fast, especially if you drive in hilly areas. Try to learn quickly not to rest your foot on the clutch pedal as you drive.

Continuously Variable Transmissions (CVT) – CVTs are a special animal. They use a belt or belt-like chain to couple two rotating cones together.  Depending on the position where the belt or chain is running in a CVT determines its gear ratio. In a funny sort of way, CVT transmissions are always slipping a tiny amount, but not enough to signal a problem.

If you do feel a slipping feeling in your CVT-equipped car, its usually the chain or belt that has worn down. This usually doesn’t happen until your car has very high mileage on it. If you feel slippage, your car needs to be brought to a mechanic for diagnosis.