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Discussion Starter #1
ok tell me if i am doing this right. i have a 20 foot gooseneck trailer. the center of the axles is almost exactly 2/3 the way back from the front of the deck. if i have 16k evenly distributed would that mean that my tounge weight would be 5300lbs???? that seems extremely high and well over gvwr.

am i doing this math correctly guys???

thanks
Reed
 

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ok tell me if i am doing this right. i have a 20 foot gooseneck trailer. the center of the axles is almost exactly 2/3 the way back from the front of the deck. if i have 16k evenly distributed would that mean that my tounge weight would be 5300lbs???? that seems extremely high and well over gvwr.

am i doing this math correctly guys???

thanks
Reed
on a gooseneck, tounge weight is usually 15%ish sometimes up to 20%. i have had 28k behind me before, 16 isnt to bad
 

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ok tell me if i am doing this right. i have a 20 foot gooseneck trailer. the center of the axles is almost exactly 2/3 the way back from the front of the deck. if i have 16k evenly distributed would that mean that my tounge weight would be 5300lbs???? that seems extremely high and well over gvwr.

am i doing this math correctly guys???

thanks
Reed

theres more to the mechanics than that.... the pivot point will be slightly forward of the front axle and the diference in bunk height to king pin height will also reduce the wieght on the pin....

if you had a single axle trailer with the bunk height the same as king pin height your calc would be correct...
 

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Discussion Starter #4
well it is a gooseneck flatbed trailer. i shouldnt have to look at bunk height right? is that for travel trailers?
 

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well it is a gooseneck flatbed trailer. i shouldnt have to look at bunk height right? is that for travel trailers?
bunk height(its a bad term here) is going to affect the height of the center of gravity of the loaded trailer.... if the center of gravity of your load is below the king pin, you will see less pin weight than if the pin is at the same height as the cog....
 

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What I did is first take the truck with a full tank of fuel and everything you are going to take in the truck, including passengers. Their are trucking companies and gravel pits and private scales, take it over the scale, weigh both axles independently. Then load the trailer on and take it back and weigh each truck axle, and each trailer axle. Then you can reposition the trailer load to give you the weights on each axle as you want. Works for ME!
 

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Discussion Starter #7
oh ok! i got ya now, well it is a lowboy trailer. the load should be below the height of the king pin
 

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What I did is first take the truck with a full tank of fuel and everything you are going to take in the truck, including passengers. Their are trucking companies and gravel pits and private scales, take it over the scale, weigh both axles independently. Then load the trailer on and take it back and weigh each truck axle, and each trailer axle. Then you can reposition the trailer load to give you the weights on each axle as you want. Works for ME!
nice way of doing it! the scale wont lie
 

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Discussion Starter #10
i hope its not that would be a TON of tounge weight even being a gooseneck
 

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Discussion Starter #11
does anyone else know a way to figure up tounge weight?
 

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Dont forget that with a fiver some of the hitch weight is on the front axel as well as the back axel.
Most fifth wheel hitches are installed a inch or 2 in front of the center point of the rear axel.

Best thing to do is wegh it like suggested earlier.Good luck.
 

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Try this, Reed

You have to take into consideration where the hitch is, not just the axles in relation to the bed. You say the axles are 2/3 way back, so I will use 13 feet from front of the load bed. Now add the hitch length. I am gonna assume this length is 7 feet. Your load and trailer is supported by two things = your hitch, and the axles. Total distance between hitch and axles in this example is 20 feet. Find the middle of your load, 16k. You said it is centered on the trailer, so the center of the load is 3 feet ahead of the center of the axles, and 17 feet from the hitch. We're gonna ignore the weight of the empty trailer here, have to add it to be closer to actual weights. 17 20ths of the weight is on the trailer, 3 20ths on the truck. 16000 * 17/20 = 13600 lbs carried on trailer axles, and 16000 * 3/20 = 2400 lbs carried as hitch weight. Now add the unloaded trailer weight to get actual weights. Your original answer of 5300 lbs would be correct if your hitch was at the exact front of the load bed. Simply measure hitch to center of axles, determine load center, and figure the ratio. Clear as mud?

HTH

Jonesey
 

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You have to take into consideration where the hitch is, not just the axles in relation to the bed. You say the axles are 2/3 way back, so I will use 13 feet from front of the load bed. Now add the hitch length. I am gonna assume this length is 7 feet. Your load and trailer is supported by two things = your hitch, and the axles. Total distance between hitch and axles in this example is 20 feet. Find the middle of your load, 16k. You said it is centered on the trailer, so the center of the load is 3 feet ahead of the center of the axles, and 17 feet from the hitch. We're gonna ignore the weight of the empty trailer here, have to add it to be closer to actual weights. 17 20ths of the weight is on the trailer, 3 20ths on the truck. 16000 * 17/20 = 13600 lbs carried on trailer axles, and 16000 * 3/20 = 2400 lbs carried as hitch weight. Now add the unloaded trailer weight to get actual weights. Your original answer of 5300 lbs would be correct if your hitch was at the exact front of the load bed. Simply measure hitch to center of axles, determine load center, and figure the ratio. Clear as mud?

HTH

Jonesey
lowering the loads center of gravity below the hitch pin also reduces the pin weight... good explanation of my earlier point...
 
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