Maintaining Your Transmission

Why should we service automatic transmissions?

• They are complex assemblies. They incorporate gears, shafts, pumps, precision valves, solenoids (electric valves) and many other precision components.
• Transmissions are expensive.
• Driving habits and use varies.
• We tend to keep our vehicles longer. 100,000 miles was very high mileage in early years. Today's vehicles last much longer and 200,00-300,000 service life is normal now.
• We drive more miles per year then we did 20 years ago! We are a society "on the go!"

Transmissions have internal filters:

• Myth: They do not require replacement.
• Fact: Transmission filters are most often forgotten (never replaced). Because most are located in the sump, replacement often requires removing an oil pan. This takes time and is messy. In fact, a few transmissions need to be disassemble to do this (very costly). Filter manufacturers design the best filters they can, but it is not possible to design a filter that will last forever and keep the transmission squeaky clean indefinitely. Eventually, transmission filters need to be replaced! Transmission filters have no method of allowing fluid to flow if they get restricted (clogged up). In order to make the filter last for 100,000 miles, it has to be "loose enough" to collect normal wear material, but not restrict flow. Unfortunately, as the filter accumulates wear particles, it's efficiency to capture wear particles decreases. Normal wear particles now are circulated in the transmission fluid. Transmission performance and life can suffer.

How complicated is a transmission service?

Transmission services today are fairly simple:

• Remove pan (when present)
• Clean the transmission internal magnet and pan
• Replace internal filter (external also, if equipped)
• Fill with proper fluid that meets transmission specifications.

What is transmission flushing? Is it something I need done?

This process has become very popular, especially at quick lube centers. It's like a blood transfusion to a human being. Often this service is performed without replacing the internal filter, cleaning the pan or internal magnet. We hear that the filter is addressed by "back flushing" the filter. This is not possible and do not believe that.

Are there differences in transmission fluids?

Today's transmissions are very sensitive to the fluids we use. Shift feel is often "calibrated" by additives in the fluid. The wrong fluid can cause harsh or even slipping shifts (although rare). In addition, we now have fluids that incorporate synthetic and synthetic blends. The primary purpose is to extend fluid life. Synthetic fluids are also helpful in lowering operating temperatures and increasing component life (increased lubrication characteristics).

When's the best time to service MY transmission?

For years, we recommended 36,000 miles or 3 years, whichever occurs first. This works fine today as it has for years! If you follow this suggested period, only the fluid drained need be replaced (no flush required).

Many vehicles are filled from the factory with "Long Life" fluid. If this applies to your vehicle, then you may consider extending the interval to 50,000-75,000 miles or 50-75 months. Use your owners manual as a guide. Keep in mind, how you use your vehicle plays a roll. Short runs with little mileage is harder then extended highway driving. Towing and hard working applications need more frequent service.

Synthetic fluids extend service life of the fluid, not the filter! We suggest not extending beyond 75,000 miles.

Some vehicles are equipped with a second filter. These are a great asset to the transmission. These transmissions are very clean and often give trouble free service. We use NTZ in-line filters on all of our rebuilt transmissions. These are excellent in keeping transmissions clean. They can be added to most vehicles easily and would assure you of a very clean transmission!