Help With Weight & Payload Management
Posted On June 2, 2019
One of the questions that drives me crazy is: “How do you manage weight distribution and payload”. While I can take all the “known’s” like, GVWR, GCVWR, GAWR etc. and understand if my tow vehicle can safely tow my trailer. The issue surrounds payload and distribution of weight between the tow vehicle and trailer. Oh sure, you can take the rig to a “weigh scale” and find out what’s what. However, to do that every time we load up – 🤬 – not possible.
On reading the Airstream Forum there was a discussion about a product called “HaulGauge”, which I found intriguing. HaulGauge measures tongue weight, payload, and gross combined weight in real-time with an OBD-II connector that communicates wirelessly via Bluetooth with an app on your Phone.
How It Works
Newton’s Second Law of Motion states: Force equals Mass multiplied by Acceleration. Mass is determined by the amount of force being exerted by the tires and monitoring the vehicle’s acceleration rate.
Force is determined by measuring slip across the torque converter as the vehicle accelerates through 15mph. There is a fixed relationship between wheel rotation and the turbine side of the converter.
Acceleration is determined by an accelerometer built in the HaulGauge device.
The rest of the HaulGauge features: tongue weight, payload, and weight-distribution, simply monitor changes in the vehicle’s pitch after the scale has been initialised with the vehicle unloaded. Needless to say this has assisted us each time we load up to go to make sure we are balanced and NOT over our payload maximum.
Addendum 2020: This product was taken over by CURT, a leading manufacturer of hitches and towing accessories and now goes by the trade name – “CURT BetterWeigh Mobile Towing Scale with TowSense Technology“