for a 5-spd at least...

I can only think of the clutch sensor (whatever it's called) that let's the car know im pressing the clutch pedal down.

I've had some starting issues... it's posted in the general forum but i just want to know from a mechanical point of view what the relationship is between the starter and the tranny. Basically, i've been having some starting troubles and I think it is linked to the bad differential bearings I have. Thanks