Drain, Refill & Filter Replacement
Under normal service (moderate highway driving excluding excessive hot or cold conditions), the manufacturer feels that automatic transmission fluid should not need periodic changing. However, if a major service is performed to the transmission, if transmission fluid becomes burnt or discolored through severe usage or if the vehicle is subjected to constant stop-and-go driving in hot weather, trailer towing, long periods of highway use at high speeds, fluid should be changed to prevent transmission damage. A preventive maintenance change is therefore recommended for most vehicles at least every 42,000 miles (70,000 km) on B Series Pick-ups and Navajo models or 60,000 miles (96,000 km) on MPV models.
Although not a required service, transmission fluid changing can help assure a trouble-free transmission. Likewise, changing the transmission filter at this time is also added insurance.
- Raise the car and support it securely on jackstands.
The torque converters on some transmissions are equipped with drain plugs. Because it may take some time to drain the fluid from the converter, you may wish to follow that procedure at this time, then come back to the pan and filter removal.
- Place a large drain pan under the transmission.
- Loosen all of the pan attaching bolts to within a few turns of complete removal, then carefully break the gasket seal allowing most of the fluid to drain over the edge of the pan.
- When fluid has drained to the level of the pan flange, remove the pan bolts and carefully lower the pan doing your best to drain the rest of the fluid into the drain pan.
- Clean the transmission oil pan thoroughly using a safe solvent, then allow it to air dry. DO NOT use a cloth to dry the pan which might leave behind bits of lint. Discard the old pan gasket.
- If necessary, remove the Automatic Transmission Fluid (ATF) filter mounting retainers, then remove the filter by pulling it down and off of the valve body. Make sure any gaskets or seals are removed with the old filter. The transmission usually has one round seal and a rectangular gasket.
- Install the new oil filter screen making sure all gaskets or seals are in place, then secure using the retaining screws, if applicable.
- Place a new gasket on the fluid pan, then install the pan to the transmission. Tighten the pan mounting bolts in a crisscross pattern to 71-119 inch lbs. (8-13 Nm) on B Series Pick-ups/Navajo models and 113-115 inch lbs. (12-13 Nm) on MPV models.
- Add 4 quarts (6 quarts if the torque converter was drained) of fluid to the transmission through the filler tube.
- Remove the jackstands and carefully lower the vehicle.
- Start the engine and move the gear selector through all gears in the shift pattern. Allow the engine to reach normal operating temperature.
- Check the transmission fluid level. Add fluid, as necessary, to obtain the correct level.
Refer to the dipstick or vehicle owner's manual to confirm Automatic Transmission Fluid (ATF) specifications. These vehicles utilize the following types of ATF:
DO NOT use improper fluids such as gear oil. Use of improper fluids could lead to leaks or transmission damage.
It is very important to maintain the proper fluid level in an automatic transmission. If the level is either too high or too low, poor shifting operation and internal damage are likely to occur. For this reason, a regular check of the fluid level is essential.
Although it is best to check fluid at normal operating temperature, it can be checked overnight cold, if the ambient temperatures are 50-95°F (21-35°C). If so, on B Series Pick-up and Navajo models, refer to the dots on the transmission dipstick instead of the cross-hatched area and level marking lines.
- Drive the vehicle for 20-30 minutes, allowing the transmission to reach operating temperature.
If the car is driven at extended highway speeds, is driven in city traffic in hot weather or is being used to pull a trailer, fluid temperatures will likely exceed normal operating and checking ranges. In these circumstances, give the fluid time to cool (about 30 minutes) before checking the level.
- Park the car on a level surface, apply the parking brake and leave the engine idling. Make sure the parking brake is FIRMLY ENGAGED. Shift the transmission and engage each gear, then place the selector in P (PARK).
- Open the hood and locate the transmission dipstick. Wipe away any dirt in the area of the dipstick to prevent it from falling into the filler tube. Withdraw the dipstick, wipe it with a clean, lint-free rag and reinsert it until it fully seats.
- Withdraw the dipstick and hold it horizontally while noting the fluid level. It should be between the upper (FULL) and the lower (ADD) marks, or notches (MPV).
- If the level is below the lower mark, use a funnel and add fluid in small quantities through the dipstick filler neck. Keep the engine running while adding fluid and check the level after each small amount. DO NOT overfill as this could lead to foaming and transmission damage or seal leaks.
Since the transmission fluid is added through the dipstick tube, if you check the fluid too soon after adding fluid an incorrect reading may occur. After adding fluid, wait a few minutes to allow it to fully drain into the transmission.