I have an Audi TT, and your CD manual. The manual has some major discrepancies in regard to the appropriate transmission and rear final drive fluids.
From the main screen, if you select the "5&6 speed 02M transmission..." link, then the "00 Tech Data" one, you will find that "G50," p/n "G 005 000" is specified for both the transmission and the rear final drive, for all codes of transmissions.
If, instead, you select the "...02M rear final drive" link from the main page, then "00 Tech data", you will find that "G51" (no p/n) is specified for the transmissions and (no type) p/n "G 052 145 S2" is specified for the rear final drive. Tranny and final codes are identical to those above.
Please clarify exactly what fluids are to be used for both the transmissions and the rear final drive, including both the type (G50, G51, ???) and the appropriate VWoA part number (G 005 000, G 052 145 S2, etc.) The formal VAG specification (i.e. G50 = VW specification 501 50), that would also be useful.
Audi periodically issues a technical service bulletin on fluids used in this market.
For a 2002 TT coupe/roadster:
02J (5 Spd FWD)2.0L (2.1 qt.)
02M (AWD)2.6L (2.7 qt.)
02D (AWD)Rear Final Drive 1.0L (1.1 qt.)
MANUAL TRANS.: Use synthetic oil, SAE 75W90, Part No. G 005 000, for rear final drive use synthetic SAE 75W90, Part No. G 052 145 S2.
CAUTION! Part numbers are for reference only. Always check with your Parts Dept. for the latest parts information.