Frequently Asked Questions About Trailers

Standard Dimensions

Sizes are described as length x width and are traditionally quoted in feet. Our standard size trailers, with internal metric dimensions, are as follows:

  • 6’x4′ (1760mm x 1200mm)
  • 7’x4′ (2060mm x1200mm)
  • 7’x5′ (2060mm x1500mm), and
  • 8’x5′ (2400mm x 1500mm)

Other sizes available upon request.

Light Duty, Medium and Heavy Duty builds are available for box trailers, as well as optional higher sides (21″).

For custom trailers you will need to nominate the length x width x height expressed in either metres, millimetres, inches or feet.

Floor Thicknesses

  • Checker plate = 2.1mm
  • Smooth (or “hot rolled sheet”) = 1.5/1.6mm

Maximum Weights

  • A trailer without brakes is limited to 750 KG GVM. GVM is Gross Vehicle Mass which means the combined mass of both the load and trailer.
  • Trailers with a GVM of 1000 KG – 2000 kg require brakes fitted to the front axle. Trailers with a GVM above 2000 KG require 4 wheel electric brakes & break away switch.
  • For custom trailers you need to estimate the maximum load weight so we can determine the appropriate suspension, chassis and braking system required. Accuracy here is critical, as repairs to a damaged trailer due to overload can often exceed the cost of appropriate strengthening at the manufacturing stage.
  • For enclosed trailers, you need to specify where your entry points are to be located as well as the style, eg. lift up door, drop ramp, side swing door etc.

Finance A Trailer

  • Yes! Austrailers Queensland now offers ezipay options on all products and purchases from $500 with no interest and no deposit!*
  • *TAP – Terms and conditions apply. Not available in conjunction with any other offer or discount.

Custom Made Trailers

Austrailers make all types of trailers to suit many purposes and are also capable of creating original customised solutions based on your needs.

Wheels and Tyres

  • As a standard in the industry, all trailers are normally fitted with second hand wheels and tyres (not retreads). All other components are new.
  • New tyres and wheels are available at an optional extra.
  • Standard road tyres, light truck or off-road tyres are available.
  • Wheel patterns are available to suit Ford, HQ, HT, 4 stud Datsun, 6 stud LC, 5 Stud LC etc


The following choices of brakes are available –

  • Mechanical over-ride disc brakes
  • Hydraulic over-ride brakes
  • Electric brakes

Electrical Wiring

7 Pin Round & Flat

  • Pin 1 = Left Indicator-Yellow
  • Pin 2 = Auxiliary or reversing signal-Black
  • Pin 3 = Earth-White
  • Pin 4 = Right Indicator-Green
  • Pin 5 = Electric brakes-Blue
  • Pin 6 = Stop Lights-Red
  • Pin 7 = Tail lights, no. plate & Clearance-Brown

6 Pin Round

  • Pin1 = Tail lights, No. plate & clearance-Brown
  • Pin2 = Left indicator-Yellow
  • Pin3 = Right Indicator-Green
  • Pin4 = Stop Light-Red
  • Pin5 = Auxiliary or reversing signal-Blue
  • Pin6 = Earth-White

Maintenance Tips

  • We all know that a galvanized trailer will most probably outlast its owner, however they are more expensive. So here are some tips to get the most out of your painted trailer.
  • Upgrading to durra gal chassis and zinc anneal sheets cost less than going to hot dip gal.
  • When storing your trailer outside always have the front of the trailer raised to allow any water to run . Jockey wheels are good for this also. If this can’t be done, then drill some drain holes into the floor.
  • If possible, cover the trailer with a cheap plastic tarp & in turn use this for covering your loads.
  • If you scratch it, touch it up. We sell touch up paint.
  • Don’t lend it to anyone.