2014 Silverado 2500 Models and Specs

[M2D]

Thanks to all here for the great information I have received so far.
My husband and I printed the Trailering and Payload Capabilities for the 2014 Silverado from Chevrolet's site.

We are thinking of buying the diesel model.
I have been paying great attention to your explanations of vehicle GVRW and how it affects how heavy a fifth wheel you can tow.

The GVRW for the diesel model is 9900 pounds. The max conventional trailering figure given is 13,000. They also give a figure for fifth wheel towing. The fifth wheel weight given for the diesel model which has the 3.73 rear axle is 17,800 pounds. The GCWR for the 3.73 rear axle on the diesel model is listed as 24,500 pounds. I am not sure what that means.

The rear gross axle weight rating is 6,200 pounds.

So what is the true story here as to how heavy/large a fifth wheel can be safely towed by the diesel model? We do not want a large fifth wheel. We would like one about 30 feet or under so we should be OK but why does this info from Chevy say that the diesel model can tow a fifth wheel up to 17,800 pounds? It would seem that from what I have read here that a fiver that large would not work with this truck.

Am I missing something?

Michele

[RustyJC]

The maximum trailer tow rating is calculated as GCWR (24,500 lbs) minus the fictitious manufacturer's curb weight of the base model truck with only a 150 lb driver (6,700 lbs) equals 17,800 lbs. Notice that GVWR does not enter into this calculation; only later in the footnotes do the manufacturers tell you that under no circumstances should ANY of the truck's ratings (GCWR, GVWR or GAWRs) be exceeded when towing. The fact is that, when towing a 5th wheel, the GVWR is going to be your limiting factor.

Let's assume that, for sake of discussion, the 6,700 lb curb weight is accurate, and you're only going to have a 150 lb driver on board. Let's add a 5th wheel hitch (say, 200 lbs) and absolutely nothing else - now the truck weighs 6,900 lbs. The pin weight your truck can carry without exceeding the GVWR can be calculated as the truck's GVWR (9,900 lbs) minus the truck's weight (6,900 lbs), or 3,000 lbs. 5th wheels transfer approximately 20% of their loaded weight to the truck as pin weight. If you were towing that 17,800 lb 5th wheel that GM told you was acceptable earlier, then your pin weight would be 17,800 x 20% = 3,560 lbs. You're overloaded on GVWR by 560 lbs, right? (3,000 lbs maximum pin weight - 3,560 lbs actual pin weight = 560 lbs over allowable maximum pin weight). With 3,000 lbs allowable pin weight, the maximum 5th wheel weight would be 3,000 lbs / 20% = 15,000 lbs which would put you right at your GVWR.

You're not missing a thing. On single rear wheel trucks, the truck's GVWR, not GCWR or the manufacturer's maximum trailer tow rating which is derived from GCWR, is the limiting factor. If GM builds a SRW 3500, it will have a higher GVWR which might work. If not, then that's where the higher yet GVWR of the dual rear wheel 3500 allows one to tow a heavier 5th wheel.

Bear in mind, though, that every pound your truck weighs with options, accessories, cargo, passengers, etc. over the fictitiously low 6,900 lbs we assumed above will have to come off your allowable pin weight to stay within your truck's GVWR.

Rusty

[M2D]

And also then to be on the safe side we should try to stay 20% below the maximum we can have for the pin weight? Is that right?

Michele

[RustyJC]

Although I'm not a subscriber to the "80% of rating" philosophy (I prefer to work from actual scale numbers), if you're not going to be able to determine the actual curb weight of the loaded truck before you buy it, then staying at 80% of the calculated pin weight should be relatively safe. That would be, in the case above, 3,000 lbs x 80% = 2,400 lbs pin weight, and the maximum 5th wheel trailer GVWR would be 2,400 / 20% = 12,000 lbs (a long way from the 17,800 lb trailer tow rating, isn't it?) Even then, that's only allowing 600 lbs more truck loading for passengers, options, accessories, cargo, etc. above the 6,900 lbs fictitiously low curb weight we used above. That pretty well eliminates the 55 gallon auxiliary fuel tank in the truck bed, etc.

If a 12,000 lb GVWR 5th wheel isn't enough to satisfy your wants/needs, then you need to be looking at trucks with a higher GVWR rating.

Rusty

[M2D]

Also do we need to consider the combined weight of the trailer and the items we put into the trailer? Does the amount of our "stuff" in the trailer lessen once more the size/weight of the trailer model we tow?

I understand about adding into the truck the weight of the people and things we might put into the truck. About how much does the extra 55 gallon gas tank in the bed of the truck weigh?

Thank you all so much for helping us to properly understand this information.

Michele

Michele

[RustyJC]

That's why we recommend that you size your truck based on the GVWR of the trailer - that's the maximum that it can weigh with all your stuff loaded into it. Don't even bother with the brochure dry weights or dry pin weights - they weigh more than that when they leave the factory. On the other hand, you should never operate over the trailer's GVWR, so if you size to handle that number, you'll be OK operating at some loaded weight less than the GVWR.

It's not the weight of the auxiliary fuel tank as much as the extra weight of the fuel. #2 diesel fuel weighs about 7.15 lbs/gallon, so carrying 55 extra gallons of diesel fuel is almost 400 lbs (393.25 lbs) of additional weight, plus the weight of the auxiliary tank, pump, controls, piping and wiring, etc.

Rusty

[Timay]

Great thread! Needs to be a sticky...

Tim

[SmokeyWren]

Originally Posted by M2D

The max conventional trailering figure given is 13,000.

The weight ratings are limited by the weight capacity of the component with the least weight capacity that will be used. In the case of a conventional trailer (i.e., travel trailer), that weakest component is probably the factory receiver hitch. Look on the frame of the hitch and you'll probably see a sticker or embossed area that indicates the max trailer weight is 13,000 pounds WD. (WD means with a weight-distributing hitch).

So if you replaced that receiver with one with more trailer weight capacity, your max conventional trailer weight would increase to the max that hitch can handle, up to the weight that you would exceed any other weight rating of the tow vehicle, including GVWR, GCWR, GAWRs, etc.

The fifth wheel weight given for the diesel model which has the 3.73 rear axle is 17,800 pounds. The GCWR for the 3.73 rear axle on the diesel model is listed as 24,500 pounds. I am not sure what that means.

The maximum GCWR is the gross combined weight of the rig. So the weight of the wet and loaded tow vehicle plus the weight of the wet and loaded trailer should not exceed 24,500 pounds. However you probably cannot gross 24,500 ounds without exceeding other weight ratings of the tow vehicle. And you should never exceed any of the weight ratings. The 17,800 max fifth wheel weight is called the "tow rating". As Rusty explained, the tow rating is a bogus number that you should ignore. You cannot tow a 5er that grosses anywhere near 17,800 pounds without exceeding other weight ratings of the vehicle.

So what is the true story here as to how heavy/large a fifth wheel can be safely towed by the diesel model?

I replied to that question in your other thread, so I won't repeat it here.