Check for leaks
Every time you take your car out, check underneath the car where it has been sitting to ensure that there are no leaks. If you see a leak, check it and have it fixed. It may not be the transmission but this is critical.
Change transmission fluid
Check the fluid level and condition often. Fluids need to be more of a red color than dirty brown. See your car’s owner manual on how often to change the transmission fluid. Use the right kind for your type of car. The cleaner the transmission, the smoother it will operate.
Use overdrive as often as possible
This is the highest gear, which most cars will do automatically during normal driving circumstances. In some cars you may have to switch it on or off. This allows the engine to run with lower revolutions per minute or rpm at a high speed, also giving you better gas mileage . When the car is heavier or during driving conditions such as mountainous terrain, you will need to switch overdrive off to make it easier on the transmission.
Shifting
Treatment of shifting is an important part of maintaining a transmission. There is a right way and a wrong way to shift gears with an automatic transmission. Do not shift to park or reverse until the car is completely at a halt. When moving from park to another gear, always push your brake down. Do not shift from park to another gear while your rpm’s are revved up.
Towing
In the event that your car breaks down or the need to tow occurs, be careful how this is done. Your powered wheels must never be on the road when towing. For instance, on a front wheel drive car, you will lift the front wheels and leave the back wheels on the road.