Changing the transmission fluid on the 3000 GT Mitsubishi is necessary every 30,000 miles or two years under normal conditions. If you use the for towing, the frequency increases to every 15,000 miles. Changing the transmission fluid involves emptying and refilling the fluid as well as changing out the transmission filter. Completing this scheduled maintenance keeps the engine lubricated and running smoothly. The repair requires only about an hour of time and a few tools.
Raise the front of the 3000 GT up on jacks to access the underside of the engine more easily. Make sure the engine is cool, so that you don't get burned when sliding underneath close to metal. Lie underneath the vehicle and locate the transmission drain pan in the center of the vehicle, off to the driver's side. Place a pan underneath the transmission to catch the fluid as it comes out.
Remove five bolts -- all but one -- surrounding the drain pan with the 6 mm socket wrench. Wait about 10 to 15 minutes for all the fluid to drain into the pan beneath. Place a hand on the drain pan to hold it in place and remove the final bolt. Lower the drain pan to the pan below to empty the remainder of the fluid. Wash out the pan to remove the layer of fluid.
Remove the filter beneath the drain pan with the 18 mm socket wrench. Replace it with the new filter. Reattach the drain pan. Lower the car from the jacks.
Pop the hood and locate the black dipstick in the engine between the battery and the air intake. Remove the dipstick and place a funnel in the tube. Pour in 3 qts. of transmission fluid. The type of fluid the car takes depends on the year, so read the owner's manual or contact the dealer for the specifications. Place the dipstick back in the tube and close the hood.
