4.7m (15ft) Boat Trailer: Finishing

Finishing the Trailer and getting ready for the road!

Fit the coupling using good quality bolts, spring washers and nuts. Bolt only through the top surface of the drawbar tongue - bolting through the full SHS section can cause the SHS to collapse and coupling to fail. Torque the fastenings as per the manufacturers recommendation.

Fit safety chains and shackles to the drawbar - see here for more details.

Mount the winch post to the drawbar using galvanised U bolts, spring washers and nuts.


Mount the winch to the winch post using galvanised nuts and bolts. Fit nylon rope or webbing if not supplied.

Fit the vee block to the end of the vee stem.


Fit the springs into the slippers/hangers and bolt up using galvanised bolts and nyloc nuts. Slide the axle over the springs and mount using galvanised "U" bolts, spring washers and nuts (nyloc nuts preferred)

Grease and fit the bearings, hubs and wheels and torque the stud/wheel nuts up as per the settings below.

Torque Settings for wheel nuts are

7/16" UNF 110Nm or 80 Ftlbs

1/2" UNF 125Nm or 90 Ftlbs

Fit all the wobble arms to the stems and quad arms using galvanised bolts and nyloc nuts. Use a small dab of anti seize or grease when fitting to help lubricate the moving parts. Tighten the nuts to secure the arms, but give enough clearance between the U brackets and arms to allow the arms to move freely. 

Mount the wobble rollers with washers and split pins.

Fit the keel rollers to the stems and rear roller bracket using stainless steel pins and split pins. Again put a dab of grease on the pins before fitting to give a bit of additional lubrication.

Fit amber reflectors along the side of the trailer, white reflectors on the front outside edge of the guards and red reflectors on the rear outside edge of the guards.


Double check that all lights are working correctly.

Put a dab of grease on the towball and hook the trailer up to your tow vehicle and double check that all the lights are working.

Grab a new vehicle registration form from your local vehicle registration centre, fill it out and register your new trailer. Attach your new license plate to your trailer and book the trailer in for a Warrant of Fitness.

Once the trailer is warranted it is ready for loading!

For Australian trailer builders, check with your local State Department of Transport for details on VIN, certificate of compliance and other requirements.

After around 100kms or so, go around all the coupling bolts, axle/spring "U" bolts and hanger bolts, roller beam "U" bolts and lights, and check all are in position and secure.

Good luck and happy trailering!