yes, converting to ac will eliminate the problems you're having with the dc motors. i would suggest that you contact the mfg. of your etv's, (seimans, mais, etc.) for the needed conversion pieces which should include updated speed reducers. i assume you're at sinapore airport which should mean your units are mais.

note to the rest of you, not everything discussed here refers to forklift technologies. etv's are more elevator technology than forklift.