Tongue Weight Rating
Hello, We are buying a trailer for our daughter and son-in-law. They now have a Ford Expedition with 8,900# tow rating. 80% of that is 7,120#, but they should stay below 7,000# loaded (5,500 to 6...
Forum Discussion
Both of you guys have obviously done a lot more research on this topic than I ever will and you both make good arguments. But for what it’s worth, considering my limited experience, here’s what I’m taking away from this.
When I load something into the bed of my truck, whether it’s 5 lbs. or 500 lbs., that weight is transferred to the ground first through the bed of the truck, through the frame, through the springs, to the axle and wheels, and ultimately to the ground. I can shift that weight around in the bed of the truck where the bulk of it is transferred by the back axle or I can move it forward where the weight is more evenly distributed between the front and rear axles. In either case, I haven’t placed an ounce of weight on my receiver. I can put that weight in the back of the truck (arranged however), crawl underneath, completely remove the receiver, and nothing about how the weight being transferred to the ground changes.
When I hook up my trailer using a ball and coupler setup the weight of tongue eventually gets transferred to the ground as well, but it takes a slightly different path. The weight is transferred through the hitch, through the frame, through the axles and wheels, and ultimately to the ground. The same thing happens (the same path is taken) when I insert my hitch into the receiver whether it’s a plain old 10 lb. hitch and ball or a 100 lb. WDH. Either way, the weight of the hitch starts on the receiver and is transferred to the ground.
Let’s say for instance I have 500 lbs. in the bed of the truck and 500 lbs. of weight on the receiver. There’s a net weight of 1,000 lbs being transferred to the ground…but 500 lbs. starts in the bed and 500 lbs. starts on the receiver. (Obviously what I’m talking about here ends up being payload)
If I take that entire 1,000 lbs and load it in the bed of the truck behind the rear axle I cause the rear axle to become a fulcrum point, but again, I haven’t applied an ounce of weight to the receiver. If I take that 1,000 lbs. and add it to the receiver the rear axle also becomes a fulcrum point but there’s not an ounce of weight being added to the bed of the truck. Likewise, if I put 500 lbs. in the bed of the truck behind the rear axle and another 500 lbs. on the receiver they both add up to 1,000 lbs. acting on a fulcrum point (the rear axle) but that weight originates from two different places.
Now…if I add a WDH to the equation (as I understand it) when I hook up my trailer a portion of that weight being applied to the receiver is distributed to the front axle of the truck and back to the axles on the trailer which eases the forces being applied to the fulcrum point (the rear axle). However, (as I understand it…and I could be wrong about this) the WDH does nothing to ease the force being applied to the fulcrum point by the weight in the bed of the truck.
It seems to me then the weight in the back of the TV (regardless how it’s loaded) is separate from tongue weight even though they both apply essentially the same forces to the TV. For instance, my class V receiver is rated at 1,500 lbs. tongue weight. I’m assuming (but don’t really know) that (somewhere along the line) is based on three things; (1) the construction of the receiver (how much stress it can handle), (2) how it’s attached to the TV, and (3) the towing capacity of the truck. In #1 & #2 how much weight I have in the back of the truck wouldn’t have any effect on the physical capacity of the receiver and in #3 we’re talking about the truck’s capabilities…not the receiver.
Keep in mind I never even took high school physics so I could be totally off base here, but after thinking it through this is what I came up with. Just my 2 cents….
When I load something into the bed of my truck, whether it’s 5 lbs. or 500 lbs., that weight is transferred to the ground first through the bed of the truck, through the frame, through the springs, to the axle and wheels, and ultimately to the ground. I can shift that weight around in the bed of the truck where the bulk of it is transferred by the back axle or I can move it forward where the weight is more evenly distributed between the front and rear axles. In either case, I haven’t placed an ounce of weight on my receiver. I can put that weight in the back of the truck (arranged however), crawl underneath, completely remove the receiver, and nothing about how the weight being transferred to the ground changes.
When I hook up my trailer using a ball and coupler setup the weight of tongue eventually gets transferred to the ground as well, but it takes a slightly different path. The weight is transferred through the hitch, through the frame, through the axles and wheels, and ultimately to the ground. The same thing happens (the same path is taken) when I insert my hitch into the receiver whether it’s a plain old 10 lb. hitch and ball or a 100 lb. WDH. Either way, the weight of the hitch starts on the receiver and is transferred to the ground.
Let’s say for instance I have 500 lbs. in the bed of the truck and 500 lbs. of weight on the receiver. There’s a net weight of 1,000 lbs being transferred to the ground…but 500 lbs. starts in the bed and 500 lbs. starts on the receiver. (Obviously what I’m talking about here ends up being payload)
If I take that entire 1,000 lbs and load it in the bed of the truck behind the rear axle I cause the rear axle to become a fulcrum point, but again, I haven’t applied an ounce of weight to the receiver. If I take that 1,000 lbs. and add it to the receiver the rear axle also becomes a fulcrum point but there’s not an ounce of weight being added to the bed of the truck. Likewise, if I put 500 lbs. in the bed of the truck behind the rear axle and another 500 lbs. on the receiver they both add up to 1,000 lbs. acting on a fulcrum point (the rear axle) but that weight originates from two different places.
Now…if I add a WDH to the equation (as I understand it) when I hook up my trailer a portion of that weight being applied to the receiver is distributed to the front axle of the truck and back to the axles on the trailer which eases the forces being applied to the fulcrum point (the rear axle). However, (as I understand it…and I could be wrong about this) the WDH does nothing to ease the force being applied to the fulcrum point by the weight in the bed of the truck.
It seems to me then the weight in the back of the TV (regardless how it’s loaded) is separate from tongue weight even though they both apply essentially the same forces to the TV. For instance, my class V receiver is rated at 1,500 lbs. tongue weight. I’m assuming (but don’t really know) that (somewhere along the line) is based on three things; (1) the construction of the receiver (how much stress it can handle), (2) how it’s attached to the TV, and (3) the towing capacity of the truck. In #1 & #2 how much weight I have in the back of the truck wouldn’t have any effect on the physical capacity of the receiver and in #3 we’re talking about the truck’s capabilities…not the receiver.
Keep in mind I never even took high school physics so I could be totally off base here, but after thinking it through this is what I came up with. Just my 2 cents….
