DIY Power Trailer Dolly

This trailer dolly is built using parts available at Princess Auto (in Canada) and probably Harbour Freight in the US.

Parts list:

  • 2000 lb ATV winch
  • 16 tooth #40 drive gear
  • 54 tooth #40 driven gear
  • 3/4″ keyed drive axle
  • 2- 3/4″ pillow block bearings
  • Hitch ball
  • Wheels & hub that key to axle
  • Keyed hubs for gears
  • Pivot wheel (make sure it will carry the weight
  • Metal for frame

The frame is built from some scrap 3″x4″x 3/8″ thick aluminum angle and some 1.5″x3″x1/8″ aluminum channel. The frame is bolted together.

The handle was salvaged from an old lawn mower. Power is provided through the trailer plug directly from the trailer battery, alternatively the alligator clips can be attached to the vehicle battery. Plug connectors allow for the use of a 10/3 extension cord to extend the power cord if needed. A momentary rocker switch on the control activates the trailer brakes, although the planetary gears on the winch motor seem to prevent a runaway situation.


Cable drum on winch needs to be machined down to fit drive gear hub.




Tow ball is quick release and can be changed


Showing both 1 7/8″ and 2″ balls




Trailer wire connector


Electrical adapters for using vehicle battery


Controller, black rocker switch applies trailer brakes


The following images were a request in the comments for picture of the under side and measurements.