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Transmission Fluid

Transmission Fluid

Automatic transmission fluid serves a multitude of purposes. Among other things, it cleans, cools, lubricates, transmits force, transmits pressure, inhibits varnish build-up and protects the transmission on a day-to-day basis. Automatic transmission fluid is specially formulated oil containing numerous additives to withstand grueling operating conditions. There are several different types of automatic transmission fluids and should be used according to the recommendation in your car's owner's manual. Most automatic transmissions should be checked while the engine is running. Check your owners manual to be sure. Also make sure the car is on a level surface and fully warmed up. Pull the transmission dipstick out, wipe off the end and note the markings on the end of the stick. The usual markings are "Full" and "Add 1 pint." Push the stick into the tube until it seats, then immediately pull it out to see the fluid level. Transmission fluid should be pink or red in color with the look and consistency of cherry cough syrup. If the fluid is a muddy brown or has a burnt smell, have it checked by a mechanic. As with the engine, never add fluid unless it is below the "Add" mark and never bring it above the "Full" mark. Make sure you use the correct transmission fluid for your vehicle. If you plan to add Transmission fluid yourself, you should know that fluid usually comes in quarts, but the level may not be low enough to take the full quart. Also, you will need a special funnel to get the fluid into the small tube that the dipstick came out of. Check your owners manual for the type of fluid and do not substitute anything else. Any noticeable transmission oil consumption should be checked out at a repair shop.

Owner's manual recommendations on transmission fluid changes vary considerably and may go as high as 100,000 miles or more. For best results, have your car's transmission fluid and filter changed every two years or 24,000 miles. Always use the type of fluid specified by your car's manufacturer. This information can be found in the owner's manual or on the end of the transmission dipstick. The overwhelming majority of transmission failures are heat-related, and automatic transmission fluid breaks down rapidly when subjected to high temperatures. Driving conditions such as trailer towing, quick stops and starts, ascending and descending mountains, and wheel-spinning in slippery conditions are but a few scenarios that can devastate the life of the transmission fluid. Although changing the fluid yourself is not difficult, it's probably best left to a qualified service technician.

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