I am looking to purchase a new truck and was told by some people that what I am planning on doing can get me pulled over and be given a ticket for being overweight. Technically it says that the Gross vehicle weight of the truck is 11,400lbs with a curb weight of 6500 - does that mean the trailer with contents can ONLY weigh 4,900lbs to be legal??? It says towing capacity is 15,500 ??? What is what - and what is legal?? Is towing a trailer that weighs 9,000lbs legal since that would be 15,500 - any help on how this all works would be appreciated - thanks.

The weight ratings you have to be concerned with are:

1) The GVWR of your truck
2) The GVWR of your trailer
3) The CGVWR of your truck and trailer


For my Duramax, the GVWR is 9200 pounds (a 2500HD). That means if I were to weigh the truck, to be legal, it would have to weigh 9200 pounds or less. Typically, where you approach this GVWR limit is if you hitch-up a large 5th wheel trailer (the trailer pin weight is in the bed of the truck, plus passengers and fuel --- this is a watch item for 2500HD trucks, the 3500 Dually's usually do not have this issue).

The GVWR of the trailer is similar.

The last limiting factor is the Combined Gross Vehicle Weight Rating of your truck/trailer combo. Put the whole thing (truck and trailer) on a scale and weigh it. I believe for the 2500HD DMAX, this combined weight rating limit approaches 22,000 pounds (If I am wrong, others will correct me!!). For the 3500 dually models, this CGVWR is usually their limiting factor (the DRW vehicles can usually handle the large pin weights of the 5th wheel trailers)

Towing capacity is the maximum TRAILER weight that GM recommends towing with the vehicle, and for the DMAX/Allison combo it is around 15000 pounds (note: this is the trailer weight). However, as I stated above, you cannot just hook up a 15000 pound trailer. There are other factors to consider.

I believe in the examle that you gave, you should be OK towing a 9000 pound trailer. Since you would be well within the CGVWR (22000 pounds). Depending on the model of the truck, you would need to look at the pin weight (if a 5th wheel) and its effect on the GVWR of the truck. If you are towing a travel trailer, you would need to look at the tongue weight of the trailer to make sure that you do not exceed the limits of the hitch.

Hope this helps and did not confuse,,, others will interject comments or can improve on the wording.

OC, I believe you're right. The GCWR is set by the manufacturer. The Dmax is set by GM @ 22,000 lbs.

http://www.2rvguys.com/weightdef.html

Each state has its own rules regarding trailer width, maximum trailer weight w/o brakes, total length, etc.

http://www.2rvguys.com/towlaws04.html

Yes I will be using a 5th wheel trailer - The truck is going to be a D/A 3500 Crew Cab Dually. So the Gross vehicle weight would be taken from the weight of the truck + whatever weight the trailer puts onto the rear axle - thus adding more weight. I guess that is where the 11,200 comes into effect. And then whatever weight the trailer is determined by it's contents and can be as much as you say 22,000+ without making the trucks pin weight over the 11,200??? I hope that is right.

First, I think I can say with certainty that a D/A 3500 CC Dually will safely and legally handle a 9000 pound GVWR 5th Wheel trailer. You will have a lot of margin left over for safety.

For conversation, lets say the pin weight of your 5th wheel is 20% of the GVWR of the trailer (pin weight = 20% of 9000# = 1800#). This 1800# will be the "weight" placed in the bed of your truck by the trailer. Now lets assume the unladen weight of your 3500 CC Dually is 7000 pound (you can get the actual weight later). To this 7000# unladen weight, you add passengers, fuel, tools, luggage, dogs, etc, plus the weight of the 5th wheel hitch and the 5th wheel pin weight. This is the total weight that is supported by the trucks six tires. This total weight must be less that the GVWR of the truck ( the GVWR you mention is 11,400 pounds for the 3500 CC Dually).

I believe you will have plenty of margin for the situation you describe (11400# GVWR of dually minus unladen weight of ~7000# = 3400# of useable payload). Your trailers pin weight is this example is 1800#, so you are left with 1600# for the other things mentioned.

And if you put all this stuff on a scale and the total weight of everything is less that 22,000 pounds, then you will be OK.

I just used that as a number - the trailer will most likely weigh more than 9,000lbs. It will be hauling 2 cars - extra motors etc etc. But I think I now understand the way the weight works. If I get to heavy on the pin - I can back a car in the trailer or store the motors in the rear of the trailer, or move things to shift the weight around a bit - Just stay under the maximum CGVW of 22,000 or whatever it would be with a Dually.

You've got the idea. However, with 5th Wheel trailers, it is important that you maintain a sufficient load on the pin. The 20% of the total trailer weight on the pin is nominal. You would ideally want your heavier items either over the trailer wheels or forward of the trailer wheels towards the hitch.

:exactly:

Close. The GVW is a vertical load limit. It is the maximum the truck can weigh when fully loaded. You need to figure out your truck’s net carrying capacity, which is found by adding the dry weight of the truck, plus all fluids, passengers and gear, including your fifth wheel hitch, then subtracting that amount from the rated GVW. The resulting figure will probably be around 3,000lbs for a 3500, depending on its configuration. That’s how much weight you can place in it as payload. The pin weight of a 9,000lbs fifth wheel should be well within that limit, figuring that on average a fifth wheel trailer carries about 20% of its weight on the pin. Your pin is probably going to be around 1,800 - 2,200 lb, or so depending on your particular unit. No problem for your truck. You’re not likely to run into problems until you start hauling trailers with pin weights approaching 3,000lbs. By then you’re looking at trailers with GVWs upwards of 14,000-15,000lbs. The 22,000lbs GCVW figure is the maximum the truck and trailer can weigh together. It represents the maximum horizontal load rating for the truck. People regularly exceed these limits. The truck has plenty enough grunt to handle high loads. But you are outside the factory’s stated limits when you do, which can invite liability issues should something go wrong.

TC