Slo Slide

I have a 2001 Keystone Montana 315 rls travel trailer with a slide that has slowed and seeme to be struggling at times. Have had RV techs adjust, lubricate. check and clean wiring, and I have replaced the battery in the last month. The tech has checked the inverter/ battery voltage/current during slide operation and everything checks OK. The slide motor is a Dewald MFG s/n # 005053. Could the motor just be getting weak ? The tech moved the slide manually using the override and it is smooth and (not effortless) somewhat easy. If so, can a motor be purchased w/out the transmission or gears ? Thanks, David.