Porsche 911 GT3 R 2012 Technical Manual page 64

5.8.5. Gearbox maintenance
The following work should be carried out regularly:
 Check gear ratio teeth, dogs and dog-rings
Check the shift collars

 Check the gear hub and gear roller bearings for signs of wear
and pitting
 Check the oil for signs of metallic debris
The following work should be carried out after a total running time of
approximately 30 hours:
Check the crown wheel and pinion for pitting

 Replace the pinion bearing ( 4-point bearing)
 Replace the oil filter
 Replace the shift cable
 Replace differential housing
The gearbox mount shall be replaced at a maximum running time of 50
hrs.
61