Check the transmission fluid level in your car regularly to prevent transmission damage .

Automatic Transmission fluid serves several purposes in your Automatic transmission. It is a lubricant for the gears, it carries heat away from the transmission and it is a hydraulic fluid that gives hydraulic pressure to the gears, allowing them to shift when necessary.

This is one reason you should never use engine oil in your Automatic transmission. Engine oil is NOT a hydraulic fluid.

A manual transmission might use regular engine oil or a special oil for gears. Your owners manual or the ATF dipstick will tell you what exact kind of fluid to use.

Experts say to change your transmission fluid every 30,000 miles, Check your vehicles owners manual to find the recommendations for your specific vehicle.

The Automatic Transmission Rebuilders Association says 90% of all transmission failures are due to overheating, usually as a result of the transmission fluid properties being broken down because the owner didn't replace the fluid when necessary.

Replacing or rebuilding a transmission can cost more than $2000.00 and neglecting car maintenance of your transmission reduces car safety and increases the risk of a transmission failure on the road.

Checking Transmission Fluid

Most vehicles should be running with the engine warm when checking the fluid level in the transmission.

Your owners`manual will tell you if you should check the transmission fluid when the engine is off. Make sure you are on level ground.

The transmission dipstick is often red and usually a bit lower and further from the engine than the engine oil dipstick.

The dipsticks themselves are normally labeled. Make sure you don't get them mixed up! Your transmission or engine could be destroyed by putting the wrong fluid in!

The picture below shows the ATF dipstick in my Toyota Echo.

When I checked the ATF level, as you can see in the picture below, the fluid is a little above the full line. Red is the full line, yellow is the fluid level.

There may be a full line for hot and cold. If your engine has been running about five minutes it should be close to the hot full line, if you just turned on the engine, it would be closer to the cold full line.

luckily, this isn't enough over the fill line to cause trouble. If the fluid on the dipstick looks smooth and redish, not foamy, There isn't too much ATF fluid in the transmission.

It's important to never over fill your transmission with ATF. If it gets up to the gears when they are moving, the fluid will get whipped into a foam, a little like what happens to egg whites when you beat them.

The fluid will no longer be able to lubricate the gears.
It also may cause enough pressure in the transmission to blow the front seal causing a serious leak and other transmission damage.

In this picture below, you can see the ATF residue on the white paper towel I used to wipe the dipstick when checking the fluid.

Notice it is redish-brown, the color it should be.
It also shows to be of a good consistency, not hard or sticky, but fluid enough to absorb well on the paper.

If it is very dark brown, that would indicate the transmission got hot enough to break down the properties in the transmission fluid that lubricates the gears. The ATF needs immediate replacement.

A milky color means there is probably a leak of coolant into the transmission , compromising the effectiveness of the ATF and the coolant. Get it fixed.

Any burnt smell would also indicate the fluid needs replacing.

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