Signs of a damaged transmission are very apparent. This doesn’t mean that owners can pinpoint the exact cause of a damaged transmission. However, once damage occurs, the transmission fails to respond properly when the driver shifts gears. Some signs are the engine over revving while in the “drive” gear, loud noises or difficulty in changing gears. By recognizing such symptoms early, the driver can stop operating the car to prevent further damage.
Automatic transmissions, which are the most common type of transmission in North American automobiles, are generally very reliable. They have a long life often exceeding 500,000 miles with minimal maintenance. The life of an automatic transmission can even exceed the 500,000-mile mark by regularly changing the transmission fluid and filter at intervals outlined in the owner’s car or truck manual. Manual transmissions, which have become less common in American-made cars in the past 20 years, use gear oil as a lubricant. Changing the gear oil at regular intervals often allows the transmission to last the life of the car. The automatic transmission fluid and manual transmission gear oil are the lifeblood of transmission. Simple maintenance of fluids goes a long way towards minimizing damage.
Common signs of a bad transmission include difficulty in the automatic transmission shifting gears. For example, the engine winding up without changing gears is a sign the transmission is not shifting properly. Unusual noises may accompany shifting problems. However, noises may not accompany shifting problems and still should be taken as a sign of damage. Other symptoms of a damaged transmission include difficulty in shifting into “drive” from “park”, shifting problems when the engine is cold or hot, and engine acceleration or stopping difficulties.
Diagnosing the Problem
Transmission problems are often linked to lack of transmission fluid. Generally, owners will find a dipstick in the engine compartment, although how to check the fluid level depends on the make and model of the vehicle. Owners can check the fluid while the car’s engine is running and the transmission is in “park” with the hand brake engaged. Owners must refill the fluid if it measures low on the dipstick. If the transmission fluid is low, it’s advised to check under the vehicle for leaks. Transmission fluid is red and easy to spot on the garage floor. Leaking could occur at the filler tube base, the transmission’s drain hole, between the engine and transmission or at the selector shaft, which connects the transmission to the gearshift. Automatic and manual transmissions are complicated devices and require an expert technician to repair.
Slipping and Park Problems
Older automatic transmissions may slip while the vehicle is running. It’s less of a problem with newer cars, but it still can occur. Slipping transmissions are apparent when the engine seems to rev higher or work harder to achieve a specific speed. Often the engine revs higher than normal and the car or truck does not pick up sufficient speed. This may also include a one- or two-second delay in the automatic transmission engaging when changing gears. This signals a damaged transmission or a transmission with insufficient fluid. The transmission is damaged if it in “park” but the vehicle still rolls. This points to a faulty parking pawl, which holds the transmission in the “park” gear.
- Photo Credit Jupiterimages/BananaStock/Getty Images