How to Determine Axle Placement for Tandem Trailer

Updated 09/13/2018 | Published 09/12/2018

Question:

Have a 16foot trailer with a 12foot deck on it were do the double axles Go???

asked by: Kevin G

Helpful Expert Reply:

The general rule for placement of axles on a trailer is to put them in a position that allows 10 to 15 percent of the trailer's total weight to be at the tongue. Hitting this range of tongue weight (TW) is important for avoiding issues with trailer sway. Too little TW leads to trailer sway.

You'll want to firm up the design of the trailer first, meaning first mounting permanent fixtures like tool boxes or tanks, so that their weight is accounted for when you mock up the axle positions. Some trial and error is needed to get the exact right spot. Boat trailers often need the axles to be further to the rear than on utility trailers since power boats tend to be heavier in the rear due to the motor weight being far to the back.

You can use the article I linked to help you determine the axle positions. It includes formulas to help you get to the right axle placement.

expert reply by: Adam R