How to Change the Transmission Fluid in a BMW E30


1. Warm your car's transmission by driving it around for about 10 minutes. Be careful not to go far over this time frame, since you want the fluid to be warm, but not scalding hot for this procedure.
2. Turn your BMW's ignition off and lock the emergency brake into place to prevent injury during the fluid replacement.
3. Jack your car evenly about six inches off of the ground and use extra support in the form of jack stands. You will need four jack stands near each tire in order to position the car level with the ground.
4. Find the transmission pan under the front end of the BMW--it is a square, bolted pan-like object.
5. Position the drip pan on the ground, directly beneath the center of the transmission pan. This is to ensure that any hot fluid spills into the drip pan, and not onto you.
6. Release the drain plug at the center of the transmission pan using the socket wrench. The fluid will immediately fall out of the transmission pan, so be sure that you are not in the way of your drip pan.
7. Unscrew the remaining bolts after you are confident that the majority of fluid has drained from the transmission pan. There will still be a small amount of fluid pooled in the bottom of the pan, so use caution as you let the pan down.
8. Empty any remaining fluid from the transmission pan into your drip pan.
9. Wipe the entire transmission pan with the shop rag and a touch of degreaser. Be sure to clean the outside, as well as the inside of the pan, taking caution to also clean the corners, so that the old fluid does not contaminate the new fluid.
10. Mount the transmission pan back into its original position on the transmission, using your socket wrench.
11. Remove the jack stands from under your BMW and lower the car with the jack.
12. Open the hood of thew E30 and locate the transmission fill plug near the windshield, between the center and the driver's side of the car.
13. Open the fill plug cap at the top of the transmission by unscrewing it with your hand. The fill plug on a BMW E30 is yellow and has a dipstick attached to it. The dipstick can be set aside for now.
14. Place the funnel upright into the center of the transmission's fill plug.
15. Begin pouring the new Dexron III transmission fluid into the transmission through the funnel, to avoid spilling.
16. Release the emergency brake after pouring in the second quart of transmission fluid.
17. Turn the ignition key and shift the car into each gear, holding your foot on the brake pedal the entire time. Shifting gears allows the transmission fluid to flow throughout the system, providing a more accurate reading when measuring the level of the fluid.
18. Put your BMW in 'Park' and let the motor continue to run.
19. Add only one-half of the third quart of transmission fluid through the fill plug and funnel.
20. Use the dipstick to measure the level of the transmission fluid by placing the cap back into the fill plug and immediately pulling it out. The dipstick will show you whether or not your transmission is filled to the recommended capacity.
21. Continue pouring small amounts of the third quart of transmission fluid, until the dipstick reads 'Full.' Use extreme caution not to flood the transmission, since the clean-up for such a spill would add significant time to completing this project.
22. Turn your engine off after the dipstick shows the transmission fluid at the recommended fill level.
23. Re-cap the fill plug with the dipstick cap and close the hood of your car. The transmission fluid change is now finished.