Tongue to Axle Dimensions - What's yours

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Iceman0502

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Hey guys! I need help with your trailer measurements - tongue to axle center.

My current trailer has been mainly doing kayak duty this summer. It's 4x8 flat bed with a 4 foot tongue. Length from tongue to axle center is 8 feet.

Overall tongue to axle center is 96 inches.

Whats your trailer tongue length and axle placement for a 4x8 trailer?

Thanks!
 
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Billiebob

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Best answer, check all the commercial trailer manufacturers, they do actual engineering to get that answer but I'd say yours is too short. An even load with the axle in the middle of the deck will net zero load on the hitch. You should calculate an axle position to transfer 10-15% of the load to the hitch.
 
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Iceman0502

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Thank you for your honest and simple response.

Next step is to measure the tongue weight with a scale when its flat in the garage. The plan is to move the axle back roughly 8ish inches for more of a 60/40 split.

I placed this question on another forum and people blew up. They schooled me on trailers dont have a 4 foot tongue they are all 3 foot, maybe I cant read a measuring tape, ha. Somehow my eyes must not be seeing these pages where people are creating their own trailers in backyards.
The world is such a positive and helpful universe now. (insert sarcasm here). Sorry for the small rant.
 

oldmopars

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Billiebob is correct. There are some things to think about with tongue length. The shorter the tongue is the quicker it will be to turn while backing up, too short and it turns too quick and it is a pain to back up. Longer tongues will respond slower and can be easier to back up, but require wider swing. Longer tongues will track better going down the road, shorter will follow a lot closer to the tow vehicles tracks, the long tongue will want to cut the corner a lot more.
There are advantages to both a long and a short tongue. If you are scooting around town a lot, a short tongue is great, spend a lot of time on the highway and the longer tongue is smoother and more stable. Short tongues get "twichy" at high speeds.
This assumes all else being equal, ie. that the weight distribution is correct. If you get the weight wrong and any trailer will handle really badly.
I watch a lot of offroad videos of 4 wheelers in Australia. They make some real nice off road camper trailers and all of them have really long tongues. The only down side to this seems to be the breakover angle really suffers. A short tongue would have a much better breakover angle and would not get hung up on as much stuff.
In the end both long and short have their place, you have to decide what you want out of it, then get the weight distribution correct and you will have a great trailer. I have seen people shorten the tongue for no other reason than to make it fit in the garage, it is all up to you and your needs/wants.
 

Anchor Mtn

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My general starting point for axle placement is to place the center of the axle 10% behind the centerline of the cargo area.

EX: cargo area = 96". 10% of 96 is 9.6" so center of the axle will be ~57.6"(48" + 9.6") from the front of the cargo area.
While this isnt foolproof it is a good start to a build. If you know you will be adding heavy items behind the axle, you will need to move it back more.

Tongue length effect tracking. IMHO, the IDEAL offroad trailer will have the same track width as the tow vehicle(tire width) and the same active length as the tow vehicle wheelbase. Tow vehicle wheelbase is axle center to axle center. Trailer active wheelbase is center pivot of hitch to axle center. If you have both of those dimensions the same as the tow vehicle, the trailer will track in the same footprint on and offroad and make towing it a breeze.
 

RTyler7071

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Tongue weight is very important. If it is zero or less, your trailer will oscillate back and forth eventually throwing you off the road. Your estimate of 60 of the load forward of the axle is pretty close. However, if you pinterest, there are quite a few examples of the exact formula you need to use to figure it correctly. You wil need to mock up the trailer and get a tongue weight to begin the calculations, but always remember, when you load out your trailer make sure that you evenly distribute the weight.
 

Billiebob

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Best answer, check all the commercial trailer manufacturers, they do actual engineering to get that answer but I'd say yours is too short. An even load with the axle in the middle of the deck will net zero load on the hitch. You should calculate an axle position to transfer 10-15% of the load to the hitch.
 

64Trvlr

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Another thing about having a short tongue is it will jack knife so fast when you're backing up it you won't believe it, when it jack knifes you can and probably will tear up the trailer or tow vehicle.

I would rather have an extra foot or two of trailer tongue over a short "handy" one. It will pull better, track better, back up better and be easier to use.

Good luck with your project and post some pics.
 

Jeep backroads

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Best answer, check all the commercial trailer manufacturers, they do actual engineering to get that answer but I'd say yours is too short. An even load with the axle in the middle of the deck will net zero load on the hitch. You should calculate an axle position to transfer 10-15% of the load to the hitch.
I just saw this I am trying to figure out tongue lenght.