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?

Very likely that any added weight capacity would overwhelm the CCC of the unit or the frame would be out of balance / loaded in a bad way and you could have more failures.They are balancing the capacity of the frame and the CCC of the unit with everything else on a giant sea saw that can have varied loads. The current placement is likely the safest and given the relatively low CCC of the units moving the wheels back further likely offers no benefit and perhaps could be detrimental.Then again, maybe the guy that designed it is a jackass.

so moving the tire set back is detrimental how? I'm not understanding this at all. My thinking is that it could carry more load weight wise in the rear..

If you have no weight in the garage, would that not make the tongue/pin weight super heavy?

All the TH'S I have purchased TT and 5th wheels had the wheels towards the back compared to a regular RV. The engineering department probably designed them for best balance for truck and trailer. TH'S already have a high pin weight and increased pin weight would require a med duty or OTR truck to pull it, like a semi.Numar mountaineer use to use duel's on there big 5th wheels.

Y'think that's bad ? (Not necessarily so)...how about the incredible rear overhang on some of the larger Class C motorhomes?

Does this make any sence? | Good Sam Community

The_real_wild1
Explorer
Nov 23, 2016
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
Explorer
Nov 23, 2016
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
Explorer III
Nov 19, 2016
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
Explorer
Nov 18, 2016
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
Explorer
Nov 14, 2016
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
Explorer
Nov 14, 2016
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
Explorer
Nov 13, 2016
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
Explorer II
Nov 13, 2016
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
Explorer
Nov 13, 2016
The axles on my WW 5th are far back compared to a newer attidude/cyclone/voltage.
Old-Biscuit
Explorer III
Nov 13, 2016
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