BMW V8 Automatic Transmission Fluid Change and Check Level – A4S-440Z, 540i, 540it, 740i, 740il, E39, E38
This answer is applicable for many BMWs in addition to the one listed below.
car year: 1998
car model: 740iL
Where is the plug to check the transmission fluid level and what is the procedure.
See the Spring 2006 issue of our Fast Times newsletter for an article on changing the fluid and filter on late model BMW automatic transmissions. The specific transmission shown is the A4S-440Z. This is the same as the transmission in your 740il. The A4S-440Z would be applicable to most 540i and 740i models from 1998-on. The article will discuss checking the fluid level after the fluid and filter replacement. You can use the same steps to check your fluid level.
The fill plug is not specifically shown in the article. The plug (for this transmission) is located on the passenger side, toward the rear, above the pan (on the transmission body).