My mistake regarding missing the "auto" box. Point accepted.
As for level check plug on the manual C544 M32 box this is not true. There is a plug but it is not a true level plug.
If you read eLearn and the Gear Box Oil Level Check Procedure:
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Op. 0010T41 MANUAL GEARBOX OIL CHECK LEVEL AND TOP UP IF NECESSARY
It clearly states:
- Position the vehicle on a lift.
Op. 7055B54 UNDER ENGINE PROTECTION/GUARD - R.R.
1. Remove the engine oil filler plug.
1. Unscrew the engine oil drain plug and allow the engine oil to drain out into a suitable container.
Threaded plug (a) is not used to drain and refill with transmission fluid. It is therefore not advisable to remove it from its seat.
- Clean the drain plug and the plug seat to remove any trace of sealant.
- Apply sealant (LOCTITE 510 or equivalent) to the plug threads and tighten into its seat to the specified torque.
- Add fluid of the specified type and quantity through the filler opening.
The fluid quantity specified in the table is the total amount contained in the gearbox (use if filled after servicing the gearbox at the bench) because 0.2 litres are left in the gearbox in the event of partial operations on the vehicle.
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Note the comment about threaded plug (a) often mistaken as a level plug!