Weight Distribution help needed please

This is normally Chewy's department (he's the designated math guy), but because of the holiday obligations, he has the night off.

Measure the distance between the center of the trailer tandems and the trailer kingpin. The halfway point between the trailer axles and the kingpin is the center of the trailer for loading.

If you don't know your empty axle weights, the next time you fuel up, weigh your rig when its full of fuel. The trailer axles are usually around 6000lbs lighter than the drive axles. With a little math, you should be able to load a trailer where the drives and the trailer axles are dead even.

"But Six, what if I have 2 objects?"

If you can divide the distance between the kingpin and trailer tandems in half, it should be no big deal to divide that distance by 2 once again.

 

If it's a tri axle trailer is it still the centre of the axle group

 

Yes

 

Well hold tight. Depends if state allows more weight on the rear with multiple pieces. If so move load back towards the rear a little more.

 

With items of a uniform weight over their length (coils, rebar, pipe, etc.) or multiple items of the same weight (pallets of bagged product, concrete pipe/weights, etc.), it is fairly simple as you can easily tell where the centre of gravity (CoG) is (it is at the middle-point of the item(s)). Where it gets trickier is a piece of equipment/machinery or some other odd-shaped item.

Often times the weight can be concentrated at one end, making the CoG different from the centre, or middle-point, of the item. This can apply to both length and width dimensions, which means the item(s) may have to be loaded offset to one end or one side to properly distribute the weight (you can overhang the side of a narrow trailer, so long as your total width does not exceed 102" (2.6 m)). Sometimes the CoG is marked, but most often it is not. If it isn't, the manufacturer and/or loader would be the first source, otherwise it can be an exercise in eyeballing the item and making your best scientific wild-assed guess (SWAG)... followed by trial-and-error.

 

If you are 34-34 on drives/tandems, centre the load. If you are 34-40 on the drives/split tandems, then 1-foot back from centre should do.

When I load bar steel, I tare out (empty weight) at about 11,000-13,250-8,500 with a triaxle aluminum trailer. My most recent load was 24' material, about 42,000 lbs at half tanks, weights were 11,080-31,940-31,940 (best I've ever done centering it).

As @not4hire said, if the product is uniform in weight, just build your load out from centre on a tandem-tandem setup. It's all in the experience. Scale before leaving the shipper (or as soon as you can) and get it adjusted if you need to. Ask other drivers for advice on how to load, and don't be afraid to talk to the shipper about how other drivers load it.

Take all the information you get and apply it to positioning your load properly.

 

In the US, generally, you are allowed up to 34,000 lbs maximum on a set of tandems. On some trailers, a set of split tandems (10'-2" split between axles) is allowed up to 40,000 lbs.

 

Did you get your answer or are you still confused?

While I appreciate the complement I am far from the math wizz. You simply brought out the baseball gear and I played ball. Too many people come on this site expecting someone to do all the thinking for them. You have a way of walking someone through a problem and having them work out the problem and come to the appropriate conclusion. Sign of a good teacher. It's rare to find someone who can teach AND do.