You should change the automatic transmission fluid in your Pathfinder every 25,000 miles if you operate it under normal driving conditions. Otherwise, if you operate it under severe conditions, you should change the fluid twice as often. Consult the vehicle owner's manual to find the recommended transmission fluid for this vehicle. The following covers Nissan Pathfinder models from 1989 through 1995.
Raise the front of the Pathfinder with ramps or a floor jack. Safely support the vehicle with wheel blocks and jack stands. Position a drain pan beneath the transmission. Use a hand drill to loosen the fluid pan retaining screws a little and completely remove the rear ones. This will allow the rear of the pan to drop and the fluid to drain out. Remove the rest of the screws and take the pan and gasket off the transmission.
Clean the fluid pan and set it aside to air dry. Inspect the fluid filter or strainer at this time and replace it if necessary.
Reinstall the fluid pan with a new gasket. You may use a tiny bit of sealant placed along the pan flange outside of the screw holes. Tighten the screws evenly with a torque wrench. Tighten them to 4 to 5 foot pounds.
Remove the jack stands carefully and return the Pathfinder to the ground. Measure the amount of fluid that drained from the transmission. Use a funnel to replace that same amount of new fluid to the transmission through the dipstick tube, located beneath the hood.
Insert the dipstick into the filler tube. Start the engine and let it idle for a few minutes. Move the gear selector through the gears, returning it to "Park." While the engine is still running, check the fluid level using the dipstick. Add more fluid if necessary. Otherwise, replace the dipstick, close the hood and shut off the engine.
