Does amp hr. rating on battery operated tools affect gear life?

[67tbird]

I have 18 volt Hitachi battery drill, hammer drill, and recip. saw. Recip saw would run for 10-15 minutes on the 2.5 amp battery from my drills, bought a 6 amp hr battery and works great. Recently I have been running new home runs to my new electric panel using the drill and 6 amp battery, and stripped the gears on it pretty quick(drilling through old growth pine) . I was wondering if  Amps=torque and if I had put a Hemi in front of a /6 tranny.

[BDF]

How big/ what style bits used? I think a large auger or forsner bit 'wood' take it's toll...Were you using hammer feature through wood? 

[67tbird]

5/8 paddle bit, drill only, don't think neighbors would like hammer function at 3am