I'm building a 5x10 offroad trailer that will haul my 4 wheeler. The front will have a 36x48x60 box. This box will have an arb fridge, partner stove, all my electronics and storage. There will also be a tongue box that will house my batteries. This will be a tandem axle build with either 31" or 33" tires. It will have a roof rack and a rack for a kayak. Attached is my rough design. There will be a fold out sink on one side and my 10 gallon propane tank on the other side just behind the box. I will also mount an instance water heater on the road side of the box inside a separate enclosure. I'm looking for help trying to figure out how far back my axles should be placed. Thanks in advance.
axle placement
- Thread starter Rubicon51
- Start date
60/40 lengthwise, not counting the A-frame
is the standard starting point.
But really depends on where heavy stuff goes if not right at the axle
water, propane, battery bank
Definitive result for safety in USA, should be 10% of total weight, wet & loaded is on the ball
8-12% being OK
is the standard starting point.
But really depends on where heavy stuff goes if not right at the axle
water, propane, battery bank
Definitive result for safety in USA, should be 10% of total weight, wet & loaded is on the ball
8-12% being OK
If your total trailer is 2735 pounds loaded, you should have at least 273.5 pounds of vertical down force on your coupler
billiebob
Well-known member
a tandem axle, 33s, will be like 70" fenders, the unit is only 120" long, it might look cool but it will be best to keep it on pavement. How are the axles articulated? Most light small trailers with single axles articulate thru the hitch. As an off road trailer with tandem axles and big tires most of the time 2 wheels will be airborne unless you have a super trick independent suspension.
You make a good point. I was originally going to keep it a single axle but as my design grew I thought it would be nice to have tandem. I think I will stick to my original plan with only a single.
billiebob
Well-known member
Focus on the numbers. How much weight are you hauling. What is the tow vehicle track. Matching rims. tires, track is great when it works. But a single axle trailer follows way better than a tandem especially if it is short. I drove this for 5 years, 50K miles a year, single axle tractor, single axle trailer, it was like a sports car. Tandems are crap for maneuvering in tight spaces.
Keep the single axle until you exceed the single axle capacity.
Or, you set things up that the placement of the heavy items I mentioned above can periodically be adjusted forward or back.
For example if you are doing highway speeds for a ling trip, the water tank(s) being empty might give you 10% ball weight spot on
but then filling up for the back roads segment, at much slower speeds, not as critical for safety.
A battery bank can be shifted between inside back of the axle and in the front tongue box, depending whether or not you have bikes hanging off the back receiver tube.
billiebob
Well-known member
Better to place the water over the axle, empty or full changes nothing. But who leaves town with an empty water tank so they can fill it from a stream once they hit the forestry road. and WHO would ever move the battery bank daily ????
Bicycles and kayaks are a non issue, even 4 of them.
Trailer Axle Position - Trailer Building: Where Does The Axle Go?
Build with the trailer axle position correct. Where does it go? Here are the calculations and explanations to set axle(s) in proper location.
mechanicalelements.com
I used this formula to calculate my axle location on my build. Factoring my battery on the tongue, 25gal water tank, etc, it put me within 2” of the 40/60 rule.
And something I have always wondered, it seems like moving the axle farther back has no downside other than adding tongue weight? The example is obviously a fifth wheel that changes the equation, but what other negative might there be to having the axel farther back than it typically needs to be?
The reason for my question is I have a scheme for building some kind of bumper tow camper. My tow vehicle will be a 163"WB F-150 that has the max towing package and can handle plenty of tongue weight but is a hassle to maneuver. Pushing the axel farther back might make things maneuver easier and might help me place the entry door in a more optimal spot.
The reason for my question is I have a scheme for building some kind of bumper tow camper. My tow vehicle will be a 163"WB F-150 that has the max towing package and can handle plenty of tongue weight but is a hassle to maneuver. Pushing the axel farther back might make things maneuver easier and might help me place the entry door in a more optimal spot.
plh
Explorer
How does the Coke trailer meet the 60/40 rule?