8-54If a weight-carrying hitch or aweight-distributing hitch is beingused, the trailer tongue (A) shouldweigh 10-15 percent of the totalloaded trailer weight (B).After loading the trailer, weigh thetrailer and then the tongue,separately, to see if the weights areproper. If they are not, adjustmentsmight be made by moving someitems around in the trailer.Trailering may be limited by thevehicle's ability to carry tongueweight. Tongue weight cannot causethe vehicle to exceed the GVWR(Gross Vehicle Weight Rating) or theRGAWR (Rear Gross Axle WeightRating). The effect of additionalweight may reduce the traileringcapacity more than the total of theadditional weight.Consider the following example:A vehicle model base weight is 2 495kg (5,500 lbs); 1 270 kg (2,800 lbs) atthe front axle and 1 225 kg (2,700lbs) at the rear axle. It has a GVWRof 3 266 kg (7,200 lbs), a RGAWR of1 814 kg (4,000 lbs) and a GCWR(Gross Combination Weight Rating)of 6 350 kg (14,000 lbs). The trailerrating should be:Expect tongue weight to be at least10 percent of trailer weight (386 kg(850 lbs)) and because the weight isapplied well behind the rear axle, theeffect on the rear axle is greater thanjust the weight itself, as much as 1.5times as much. The weight at therear axle could be 386 kg (850 lbs) X1.5 = 578 kg (1,275 lbs). Since therear axle already weighs 1 225 kg(2,700 lbs), adding 578 kg (1,275 lbs)brings the total to 1 803 kg (3,975lbs). This is very close to, but withinthe limit for RGAWR as well. Thevehicle is set to trailer up to 3 856 kg(8,500 lbs).If the vehicle has many options andthere is a front seat passenger andtwo rear seat passengers with someluggage and gear in the vehicle aswell. 136 kg (300 lbs) could be addedsrx.book Page 54 Monday, June 8, 2009 8:28 AM
