It is easy to forget about the device your car relies on to propel it down the road, and it’s not the engine! We’re talking about the Transmission. The transmission requires regular servicing, but most drivers neglect it. “Neglect” is the reason why transmission shops are making a fortune replacing burned out automatic transmissions.
At Pro Trans, we recommend you have your car, truck or van’s transmission fluid (ATF= Automatic Transmission Fluid) and filter replaced every 30,000 miles (unless you have a new vehicle that is filled with Dexron III ATF which is supposed to be good for 100,000 miles).
ATF Wears Out! Why?
An automatic transmission generates a lot of internal heat due to friction: the friction of the fluid circulating inside the torque converter, friction created when the clutch plates engage, and the normal, everyday friction created by gears and bearings working to move your vehicle down the road.
Automatic transmission fluid (ATF) heats up immediately once your vehicle is in motion. Average daily driving will raise fluid temperatures to 175 degrees F., which is a normal operating temperature. If ATF temperatures can be held to 175 degrees F., ATF will last almost indefinitely, up to 100,000 miles. But if the fluid temperature goes much higher, the life of the fluid is compromised. Driving in stop and go traffic, traffic lights and around town driving usually causes transmission temperatures to go above 175 degrees. And once that happens, over time, trouble begins.
At elevated operating temperatures, ATF oxidizes, turns brown and takes on a “burnt odor”. As heat destroys the fluid’s lubricating qualities and friction combating characteristics, a resin-like film begins to form on internal parts (such as the valve body) which interferes with the smooth operation of the transmission. When the temperature gets above 250 degrees F., rubber seals begin to harden, which leads to leaks and pressure loss. The transmission begins to slip, which only aggravates overheating even more. Eventually the clutches burn out and the transmission fails. The only way to repair the damage is with an overhaul — a job which can easily run upwards of $2,000 on a late model front-wheel drive car or minivan.
As a rule , every 20 degree increase in operating temperature above 175 degrees F. cuts the life of the ATF in half!
At 195 degrees F., fluid life is reduced to a little more than 50,000 miles. At 220 degrees, which is commonly encountered in many transmissions, the fluid is only good for about 25,000 miles. At 240 degrees F., the fluid won’t go much over 10,000 miles. Add another 20 degrees, and life expectancy drops to 5,000 miles. Go to 295 or 300 degrees F., and 1,000 to 1,500 miles is about all you’ll get before the transmission burns up.
If you think we are trying to scare you and exaggerate so we can sell a “Transmission Service”, consider this fact: According to the Automatic Transmission Rebuilders Association, 90% of all transmission failures are caused by overheating. Most transmission failures can be blamed on worn out fluid. Routine service will absolutely prevent this from happening!
In most vehicles found on the road today, the automatic transmission fluid is cooled by a heat exchanger located in or on the radiator. Hot ATF from the transmission circulates through a loop of pipe and hoses, and cooled by this “transmission cooler”. Well, it’s not really “cool” because the radiator may be running between 180 to 220 degrees!
The cooling effect accomplished by the “transmission cooler” is marginal at best. ATF that enters the transmission cooler at 300 degrees F. leaves at 240 to 270 degrees F., which is only a 10 to 20% drop in temperature, and is nowhere good enough for extended fluid life.
Towing a trailer, driving in hilly or mountainous terrain, driving in hot Redding, CA weather, stop-and-go driving in city traffic, off road use or driving in the snow, etc., can push ATF temperatures beyond your cooling systems ability to maintain safe limits. Problems in the radiator cooling system itself such as a low coolant level, a defective cooling fan, fan clutch, thermostat or water pump, an obstructed radiator will diminish ATF cooling efficiency. Occasionally, transmission overheating can lead to engine coolant overheating! There’s a demand for auxiliary add-on transmission coolers. Ask us about this option!
What Is Auxiliary Cooling?
An auxiliary transmission fluid cooler is easy to install and can substantially lower fluid operating temperatures anywhere from 80 to 140 degrees! Typical cooling efficiencies run in the 35 to 50% range. If you tow a trailer, 5th wheel, drive in hilly terrian etc., we think you should consider an Auxiliary Cooling System.
About ATF Types
What kind of automatic transmission fluid should you use in your transmission? The type specified in your owner’s manual or printed on the transmission dipstick is a correct choice.
For older Ford automatics and certain imports, Type “F” is usually required. Most Fords since the 1980s require “Mercon” fluid, which is Ford’s equivalent of Dexron II.
For General Motors, Chrysler and other imports, Dexron II typically specified.
Some newer vehicles with electronically-controlled transmissions require Dexron IIe or Dexron III fluid. GM says its new long-life Dexron III fluid can be substituted for Dexron II in older vehicle applications.
Using the wrong type of fluid can affect the way the transmission shifts and feels. Using Type F fluid in an transmission that calls for Dexron II may cause hard shifts. Using Dexron II in a transmission that requires Type F may allow destructive slipping under heavy load, which can destroy transmission components like the clutch!
Contact Us For Your Transmission Service!
Servicing a transmission is a messy job because unlike changing the engine oil, there is no drain plug! Most of the time, fluid is spilled all over you and the floor of your garage or worse, driveway.
Give us before you come over. We can do it for you! It’s easy!
Pro Trans
530-722-9500
1113 Center St.
Redding, CA. 96001
