[Dennett]

Has anyone given a detailed instruction on how to change transmission oil on 2003 M3 SMG Convertible.I have just purchased one and am brand new to the forum.

[TboneM3]

Jack car up and place 4 jack stands in appropriate places
Remove black plastic cover (like 5 or 6 8mm hex screws holding it and fuel filter cover)
Loosen fill bolt (17mm hex) on the driver side of transmission first then,
Place pan or bucket under drain bolt and remove drain bolt (17mm). About 2L of fluid will drain.
Replace drain bolt. No washers or gaskets are required for either bolt. Bolts are the same for drain and fill.
Pump 1.8-1.9l of gl4 75w80 gear lube into tranny until it starts to drip out of fill hole. Replace fill bolt.

SMG tranny is the same as 6mt tranny.

This is a very basic job. If you need a DIY, you probably shouldn't be doing it by yourself. Are you comfortable working under the car with it on stands? Do you know the correct points to lift the E46 m3? Where are you located? Members like me are willing to help, often.