10 things to NEVER do in an automatic transmission

You may not know how an automatic transmission works, but you probably drive one every single day.  Did you know there are a few things you should NEVER do while driving an automatic?  These mistakes many people make can cause catastrophic damage to your car, and put you on the hook for some major repair bills if you aren’t careful.  Thankfully, they are all easy to avoid, and we are giving you the advice on how to keep your car in good shape longer.  Read this quick top-10 to make sure you aren’t destroying your transmission.

Number 10: Never rev the engine before putting the car in gear


Teenagers seem to love doing this one. Oh to be young and have parents to pay the repair bills again….. Many people call this “Neutral-Bombing” and it involves revving the engine with the transmission in neutral, and then dropping it into drive to smoke the tires. The “bomb” part of the term refers to the heavy shock load placed on the transmission that has a tendency to leave the internal components looking like the aftermath of a grenade. Simply put, don’t be an idiot.


Number 9: Never park on a hill without using your emergency brake

parked_on_hill.jpgThis is one 99% of us are guilty of. The emergency brake is also called the parking brake for a reason. When you put your car in “Park,” a small component called a “parking pawl” gets wedged in between gear teeth to keep the car from moving. This piece is pretty small, and can sometimes fail causing the car to go rolling down the hill. Over time, the parking pawl or the gear it engages can become worn and notched, causing the car to get “stuck” in park when the weight of the car rests on the pawl. Do yourself a favor, and set the parking brake before putting the car in Park. Brakes are cheaper and easier to fix than transmissions are, anyway.

Number 8: Never coast in Neutral

Coasting down a long hill in neutral may seem like a simple way to save gas, but in reality, you could be harming your transmission. When a transmission is in Neutral, the fluid pump is moving little to no fluid through the transmission. What you may not realize is half the components in your transmission are still moving when rolling in neutral, and they need the fluid to keep them cool and lubricated. With the reduced fluid flow, wear and damage occurs at an astounding pace. The fuel savings is negligible, and the repair bill will be a lot more than the few pennies saved.

Number 7: Never use the incorrect fluid


Years ago, nearly all automatic transmissions used the same “Red Kool-Aid” fluid. These transmissions also were very simplistic, sporting only 2 or 3 gears, no electronics, and had primitive friction materials in them. Fast forward 50 or so years, and transmissions now have 8 and 9 speed transmissions, and the materials the transmissions are made of weren’t even discovered or invented 50 years ago. With this evolution of the technology came an evolution of fluid. Modern fluids have a lot of new technology, and they can vary from car to car. Using the wrong fluid can completely ruin a transmission, so be careful and use the right stuff.

Number 6: Never tow the car with the drive wheels on the ground

tow.jpgSimilar to coasting in neutral, never tow a car with the drive wheels on the ground. If you don’t have the car running and the transmission in gear, no fluid is making its way to critical components that will still be moving if the wheels are rolling. As a result, the components all overheat and “weld” themselves together. The transmission will end up beyond repair. Just Don’t.

Number 5: Never shift without coming to a complete stop

This one is kind of the reverse of #10. If you are backing out of a parking spot, and shift to drive while you are still rolling backwards, you force components to change direction rapidly. This is like being pushed onto a treadmill going the opposite direction. Same goes for shifting into park while the car is rolling. Ever walked into a wall? Not fun. Don’t do this to your transmission unless you like spending lots of money fixing things you broke.

Number 4: Never tow in Overdrive

tow_trailer.jpgMany people misunderstand what overdrive is. Overdrive is simply the highest gear in your transmission and is designed for gas mileage. It allows the transmission to spin faster than the engine so you can maintain highway speeds with a low engine rpm. When towing, overdrive doesn’t provide the torque necessary for the extra weight. This causes the transmission to shift in and out of top gear a lot, increasing heat and wear which will eventually cause transmission failure. To prevent this, turn overdrive off, or hit your tow/haul button. Consult us or your owner’s manual for more information.

Number 3: Never drive with the low fluid light on

Transmissions rely on fluid to make everything work. Automatics operate on fluid pressure, and the fluid also helps keep everything cool and lubricated. If you run an automatic transmission low on fluid, you will quickly destroy it. It keeps us in business, but we hate seeing you spend money you could have avoided.

Number 2: Never rock a car back and forth

stuck.jpgRemember in driver’s ed when they taught you to rock a car back and forth to get out of the snow? Yeah, about that. DON’T DO IT. What happens when you rock back and forth is that you generate a lot of heat from the clutches inside the transmission engaging and disengaging. In addition, you are forcing components to change directions rapidly. All of this will ruin your transmission. If you are stuck in the snow, try putting kitty litter, sand, or cardboard under your tires for traction. If that doesn’t work, call a tow truck for help. The $75-100 you pay the tow truck will be FAR CHEAPER than rebuilding the transmission you smoked trying to get unstuck.

Number 1: Never drive hard without giving the transmission time to warm up.

Going into winter, this is our #1 tip. Never drive your car hard without allowing it to warm up. In winter, fluids thicken and move more slowly. This means that they don’t lubricate as well, and in your transmission, they don’t apply pressure on the hydraulic components as well either. Give the car a few seconds to run before you shift into gear, and drive gently for the first 10 minutes or so until everything gets warmed up. You wouldn’t get out of bed and immediately run a 400-meter sprint, would you?

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