Trailer Weight Distribution Question

[EastTnFarmboy]

There are several threads on this site where proper distribution of weight on a trailer is discussed. In general, it seems that in order to avoid "porpoising" and other trailer control problems the weight should be as close to the front of the trailer as possible without exceeding the appropriate tongue weight. As has been discussed in other threads, sometimes it takes a while to find that certain "sweet spot".

This morning I was working with a loaded utility trailer and noticing how heavy the tongue was in comparison to a trailered boat of approximately the same weight. I started pondering the fact that with most boats, a majority of the weight is in the rear because of the design and the fact that the motor is in the rear.

I am sure it is a simple reason that I am just overlooking, but why do you not experience control problems when pulling a boat where the weight is distributed toward the rear instead of as far forward as possible? If it is merely trailer design, what makes it work?

There is no overwhelming reason I need to know, I am just curious. I'm sure that some of you who are much more knowledgeable than me can explain this.

Thanks!!

 

[Patches]

If you really look at a boat trailer,whether it's a single, tandem, or tri-axle in design, the axles are placed well back on the trailer so as to support the center of the the load, not necessarily the center of the boat

 

[SnowRidge]

Look at where the axle(s) is located in relation to the extreme ends of the trailer/ load combination. It will be well behind the 50% point. Simply put, moving the axle to the rear puts more of the total weight on the coupler ball. The design axle placement takes into consideration the weight distribution of the type of boat that the particular trailer is designed to haul.

 

[jayhaitch]

Boat trailers tow well with only 5% tongue weight. Utility/RV trailers need 10-15%. It's the length of the trailer tongue and weight concentrated closely over the trailer wheels that does it. Utility trailers have a short tongue (tongue tied?) and variable types of load distribution. Boat trailers ensure the boat is loaded in an identical fashion each time. I think of a lever arm/fulcrum diagram.

My Continental Cargo utility trailer owners manual states a "bumper pull" type of trailer should have a 60/40 weight distribution front to back, with the dividing point a line drawn in the middle of the wheel (or wheels if tandem axle). They say a gooseneck/5th wheel trailer should be loaded 70/30.

 

[BigCrzyRdNeck]

In my experience if you need load distribution hitches you dont have enough truck. I hauled 14,000 on my receiver and never had problems went right down the road no sway. Though I dont play went it comes to towing I own a Ford dually.

 

[George2615]

In my experience if you need load distribution hitches you dont have enough truck. I hauled 14,000 on my receiver and never had problems went right down the road no sway. Though I dont play went it comes to towing I own a Ford dually.

Not to nit pic but you didn't mention what Ford dually you own. According to the Reese Hitch website a 2007 or 2008 F350,450, or 550 with a class 5 hitch is only rated to tow 12000# with 1200# of tongue weight or up to 17000# and 1700# tongue weight but only with a weight distribution hitch. The manufacturers hitch rating along with the vehicles maximum tow rating is what sets the amount of weight you can tow. Anyone can mount a class 5 hitch on a Ranger but that doesn't mean the Ranger can tow 12000#. I'm sure you're dually could tow more but you are stressing the hitch by going over the mfg. specs which are stamped on the hitch.

 

[BigCrzyRdNeck]

OK sorry but one is an 82 flatbed it will out haul my 97 dually the 82 is my project truck its in the plans to get a 6v92 detroit one day. but any way one is a 82 and the other is a 97 crew cab. i will put pics on here once i figure out how to make a pic profile.

 

[Diamondpilot]

I have ran into this many times. A one ton is not a one ton. I have a 2006 F-350 4x4 Powerstroke and the GVWR is 11,400# . My neighbor has a 2007 GM 3500HD 4x4with the Diesel and Allison. His GVWR is 9,900#. Thats 1,500# difference. He used to use my 2004 F-250 4x4 Powerstroke to pull his trailer from time to time, its rated at around 10,500#, and it handles the weight much better than his new GM. I never realized there to be that much difference but there is. Lesson is look at what spring package it has before buying. All my truck are extend cab short beds so they will fit in the garage. His truck is a 4 door long bed bus. Anyway we went to get firewood last week and mine did not squat a bit, his on the other hand was sagging good. Granted he has a slightly bigger bed but we had about the same load in the trucks.

Chris

 

[MrJimi]

When I load a heavy weight on a trailer, I look at where the bumper is in relation to ground and I load it on and I make sure that I have the back of truck a little lower than it was and all works just fine without playing with a scale
and if you look at my avatar with a 14K trailer with a 6,500 skid steer on it, it sets level and fine. And NO I do not take that on the road, I was just playing with my toys
Jim

 

[skipmarcy]

When I load a heavy weight on a trailer, I look at where the bumper is in relation to ground and I load it on and I make sure that I have the back of truck a little lower than it was and all works just fine without playing with a scale
and if you look at my avatar with a 14K trailer with a 6,500 skid steer on it, it sets level and fine. And NO I do not take that on the road, I was just playing with my toys
Jim

Same thing for me, with different implements on my tractor I have to vary exactly where I place it on the trailer and it only takes just several inches either way to make a big difference. I watch the squat of the truck as I'm loading to get it close, then a good indicator is to look at distance between the body to axle bumpers under the truck - you need a few inches clearance minimum for suspension travel. Mine has a good 3" or 4" clearance when loaded. My trailers run nice and level at proper tongue weight - my dump has an adjustable coupler and I use a 6" rise ball mount to have my equip. trailer level with the tractor on it, it's a fixed coupler.