Does this make any sence?

[KKELLER14K]

I'm throwing this out there for anyone who could explain this...why would a toy hauler have it's wheel base more in the middle of the frame where as most of the weight could or would be stored towards the rear of the RV? Semi truck trailers have their tire sets at the rear of the trailer(yes more tires) ... but WHY? Would it make sense that if you haul a heavier load in the rear that the tire set is closer to the rear to the overall load of the trailer? Why don't we use the dually tire sets on these bigger RV's?? Construction trailers use the dual tire concept am I missing something or stirring the pot?

[The_real_wild1]

My Raptor has the axles pretty close to the centre. Tows pretty good and steers nice as well. Its funny. As I load it up with the sxs and water,etc it tows better then empty. 13,700 empty and about 17,400 loaded.

[copeland343]

Our 5th wheel toy hauler has both axles under the garage area. The forward axle is at the front of the garage area. The side by side sits over the axles. Truck squats 2 inches with or without the SxS in the 5th wheel. Only problem we have is the axles back makes it hard to back into some tight sites. Makes for a long wheel base. Nice thing is very little rear overhang.

[JIMNLIN]

Triaxles are popular with long toy haulers/stock trailers/etc over tandem axle trailers for several reasons.

http://www.lakotatrailers.com/charger/c8x17eh/
LEQ hore trailers are a good example for axles in the rear of a long trailer and heavy hitch loads vs conventonal placed axles.
Some LEQ require a 450/4500 truck with their 11000 lb RAWR as a minimum to carry these trailer hitch weight.

[drmopar]

Great question. In my case I wanted a Toy Hauler that would be stable with different loads. I went with a Stealth tri-axle. What a difference over tandems. The triple axles spread the loads across the frame better.

[OH48Lt]

I had a 33' KZ toy hauler 5ver, and those wheels were forward of the garage area. One reason was to give as much floor width as possible inside the garage. It's really needed if you are hauling 2 full-size ATV's side by side.

[1Wheeldrive]

I suspect that part of the reasoning for axle placement is to minimize big changes in weight on the pin for towing stability purposes.
I have a 2012 Voltage 3200, and the pin weight of the unloaded trailer was around 2,700 pounds. The pin weight of the trailer loaded for vacation with one 650 - 700 pound ATV, one 275 pound dirt bike, several hundred pounds of tools, riding gear, camping gear, dog food, etc. and about 40 gallons of gas in the gas station, and about 50 gallons of water only reduced the pin weight by about 100 pounds. Almost all of the payload goes on the axles.

[sin_cal_hd]

The longer trailers put the tanks in front anticipating caring a liquid load (fresh, gray, black) in front of axles and cargo load at the rear. Like previously stated. It's weight distribution over the trailer axles and not so much for the TV. Trailer mfg build trailers and expect you have the proper tv.

[jmtandem]

No it does not Solve pin weight.

It can be used to see affect of axle placement on pin weight

Yea, it is the teeter totter formula that allows for the distance of the the fulcrum length or the weight needed for a certain length that would offset the weight/distance on the other side of the pivot point.

[wagon_b0y]

The axles on my WW 5th are far back compared to a newer attidude/cyclone/voltage.

[Old-Biscuit]

jmtandem wrote:

Pin weight.........axle load ratings based on the fulcrum/lever principle
ie: F = (W x X)/L

"Pin weight....axle load ratings based on the fulcrum/ lever principle." Are you sure solving for F gives the pin weight? Or does it give the fulcrum length needed to offset the weight and distance to the left of the pivot point? I played with some numbers and could not get the formula to give a pin weight that has to be heavier than the offset only weight or the pin would weigh insufficient to stay on the hitch (ie no real down weight, just offset weight). Can you provide a real world example how this solves for pin weight.

No it does not Solve pin weight.

It can be used to see affect of axle placement on pin weight

[jmtandem]

Pin weight.........axle load ratings based on the fulcrum/lever principle
ie: F = (W x X)/L

"Pin weight....axle load ratings based on the fulcrum/ lever principle." Are you sure solving for F gives the pin weight? Or does it give the fulcrum length needed to offset the weight and distance to the left of the pivot point? I played with some numbers and could not get the formula to give a pin weight that has to be heavier than the offset only weight or the pin would weigh insufficient to stay on the hitch (ie no real down weight, just offset weight). Can you provide a real world example how this solves for pin weight.

[drittal]

hone eagle wrote:
Marketing - keeps the pin weight down so they can sell you a "1/2 ton towable" rig.
Pick ups have a massive pulling ability but less (in proportion) weight carrying ability. a recipe for disaster if you are not careful, as on the bounce you can unload the rear tires enough lose traction or even contact (with the road) to jack knife .

This is becoming common in the bumper pull TH. 10,000lb gross TH with 800-900lbs empTY tongue weight so the mfr can claim 1/2t towable. Too bad it sways like a mofo with anything larger than a pop tart in the garage area. SMH

[Dirtclods]

DutchmenSport wrote:
Every toy hauler I've looked at has the axles farther to the rear (5er and TT versions) opposed to their sister non-hauler (same length, brand, and manufacturer). Non-Haulers do have the axles forward more.

I'm sure every "hauler" comes with a weight limit for the garage area. This is to ensure the tongue weight does not decrease so much, the tail is too heavy, reducing weight on the hitch, causing bad towing conditions.

Move the axles farther back, and the hitch weight or tongue weight increases tremendously. It doesn't take much axle positioning to the rear to cause an excessive amount of hitch weight, that even a one ton would have problems with. So manufacturers have done the "math" to determine the best location for the axles with a recommended "do not exceed" wight for the garage to ensure good hitch weight and still be able to carry a load in the garage.

(I'm sure every "hauler" comes with a weight limit for the garage area) Nope

[KKELLER14K]

Wow...now I really learned something here...thanks Old-biscuit. Jmtanandem you explained that really well. I get the 80/20 load concept. It is common sense that you would not overload the kingpin on a conventional truck. I had not noticed that the toy hauler design already has taken into consideration that the wheel base is a bit further rearwards. This makes me want to take even a closer look at how trailers are designed. This is good discussion and we all learn something so thanks everyone for your input.