Springs are rated in so many pounds to compress them an inch, at least on linear springs (like torsion bars are). For a quick estimate, measure the height in front, then slap on some weight (have someone get on the bumper for example) and measure the height again (to the same place). Find the height change (in inches) for a give weight (in pounds) and divide pounds by inches to get the spring rate of that end of the truck. Then use that to determine the sag for a given amount of weight added to the truck.

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
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