How to Select Weight Distribution System Spring Bars to Match Measured Trailer Tongue Weight

Question:

Hello...i have a 2015 Ram 2500 4x4 Diesel truck pulling a 31 foot travel trailer weighing in at 7000 loaded. Truck carrying about 500lbs in the bed. I have the the rounded spring bars attached by the Strap Tech system. Wanted to see which weight of bars do I need. Thank you

asked by: David B

Expert Reply:

Weight distribution system spring bars should be selected based on the actual measured trailer tongue weight (TW) when it is fully-loaded and ready for the road, with full water and propane tanks and all gear and supplies in place. Scale # e99044 makes this measurement process easy but other methods are shown in the linked article.

To this measured trailer TW you will add the weight of anything in the bed of the truck that sits behind the rear axle, say a generator or big loaded cooler, as this will appear like trailer TW to the weight distribution/sway control (WD/SC) system. Weight forward of the rear axle, such as a crossover-style tool box, does not need to be added.

A properly-loaded trailer typically has TW in the range of 12 to 14-percent of its gross weight. For a 7K trailer that is loaded correctly you would have a TW figure of between 850- and 1000-lbs. To this you would add the behind-the-axle cargo weight.

All WD/SC systems work over a range of trailer TW, usually a range of several hundred pounds. Often the bars themselves can be changed out to provide a different range of compatible trailer TW. This means that sometimes a new trailer does not need a whole new system, just new bars rated for the TW of the new trailer.

All of our round spring bars are shown on the linked page. Helpful articles and a video on WD/SC systems are linked for reference.

expert reply by: Adam R