The E30 is the second generation of the popular BMW 3 Series. The E30 was sold in North America from 1984 until 1991 when it was replaced by the E36 generation of the 3 Series. With handsome looks and impressive performance, the E30 is a great used car buy. The E30 was available with a manual transmission or an automatic. Automatic transmissions must have the fluid changed periodically to ensure that they shift smoothly and reliably.
Drive the car for a short time so that the transmission fluid is warm before changing it. Make sure it is not extremely hot, though, as you will be working around hot components and oil.
Park the vehicle on a flat surface. Raise the vehicle at all four corners with a jack and lower it onto jack stands.
Place a drain pan under the transmission pan, which is square and is bolted to the bottom of the gearbox. Remove the transmission drain plug with a socket and a ratchet. Let the transmission fluid drain into the pan.
Remove the small bolts around the perimeter of the pan, leaving one bolt in place. Pull the pan down on the end opposite the bolt and let the remaining fluid drain out. Remove the last bolt and the transmission pan.
Unbolt the filter from the transmission. The filter will be visible once the pan is removed. Install a new filter and bolt it into place.
Clean the inside of the transmission pan with rags and a degreaser so that it is completely free of oil and debris. Clean the lip of the pan so there is no gasket material as well as the bottom of the transmission.
Install a new gasket onto the pan then bolt the pan back to the bottom of the transmission. Tighten the bolts with the socket.
Open the bonnet. Remove the yellow cap for the transmission oil, located in front of the windshield and between the centre and driver’s side. Pour fresh transmission fluid into the fill hole with a funnel. Pour in two quarts of fluid.
Start the engine (with the car still supported) and shift the transmission through the gears while depressing the brake pedal. This will let the transmission fluid flow throughout the transmission.
Place the gearbox in "Park" while the engine is running. Check the level of the transmission fluid by placing the cap and dipstick back into the fill hole. Continue adding small amounts of fluid until the dipstick shows that the fluid level is full. Do not overfill the transmission. Tighten the cap. Lower the car back to the ground.