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Discussion Starter #1 (Edited)
Sorry in advance for the long post. I tried to pare it down as much as possible.

Often people will come here and ask “how much can my truck tow?” or “what is the towing capacity of my truck?” There is a thread going right now concerning towing a fifth wheel with a 1500. I thought I would try to put some information together to help people understand what their towing capacity is and how to go about figuring out “how much can my truck tow?”.

I'm guessing that there will be some disagreement, people following up with posts of their own stating that they "tow a 15,000 pound goose neck 5 days a week with my 3.7 Dakota" and how wonderfully it handles the load. Well, good for you. If however, one wishes to stay on the correct side of the law (not to mention good sense) there are some specific guidelines that are easily followed to determine safe towing weights.

There are several important abbreviations and numbers that we need to know in order to establish our towing capacities. There are also some myths that need to be dispelled. First, although there are others, here are a few common myths.

Myth #1. My truck is rated to tow 6000 lbs. so I can purchase a trailer that weighs 6000 lbs.

In regards to number one, there are several things to bear in mind. The brochures that travel trailer manufacturers print are usually very optimistic where weight is concerned. Usually, these weights reflect the base model of their trailers. Let’s add some accessories to the trailer.
Air Conditioning – 150#
Awning – 50#
Spare tire – 40#
Microwave – 35#
Extra deep cycle battery – 45#

While we’re at it, let’s add the stuff we need to go camping.

40 gallons of water – 336#
Full propane tanks – 75#
Food for 4 for a week – 40# (minimum)
Luggage or clothing – 20#
Television – 35# (gotta watch a movie, huh?)
Camp chairs for 4 – 60#

So, we’ve added almost 900 pounds and we haven’t even addressed things like silverware, cooking utensils, games and toys for the kids, toiletries, etc. So in regards to number 1 above, we have to be realistic about how much our loaded trailer is going to weigh.

Myth #2. My truck can be upgraded to tow more weight by adding air bags, etc.

Wrong. No matter what you do to your truck, all of the ratings (GVWR, GCWR explained below) remain the same. (It is my understanding that this may actually not be true in Canada. Since I am not familiar with Canadian law, I will not comment on this one way or the other for our northern brothers) Although adding accessories to your vehicle may help it’s ability to tow, it will NOT change the factory ratings. If you are found to be at fault in an accident and are found to be overweight, you are not going to be able to say “but I added air bags and heavier springs!”. Nope, if it’s me that you hit, I’m going to sue your butt off. And you know what? I’m going to win. All of those numbers that are affixed to your vehicle by the factory are required by the government and have to be backed up by factory testing. Once that vehicle leaves the factory, those numbers are written in stone.

Myth #3. Tow ratings are based on how powerful the engine is.

Although engine size, horsepower and torque are part of the equation, those are not the only factors involved. Chassis, tires, brakes, etc, etc, etc, are involved. The bottom line is, just because your truck can pull it doesn’t mean that you should. You not only have to be concerned with power, you have to concern yourself with stability and stopping power. Stay within the factory limits.

Now for some terms that everyone contemplating towing a trailer should understand.

GVWR – This stands for Gross Vehicle Weight Rating. This number is usually on a sticker on the driver’s side door frame. This is the maximum that the vehicle should ever weigh, including a full fuel load, passengers, added accessories, etc. In short while moving down the road, the vehicle should NEVER exceed this number.

GCVWR – This stands for Gross Combined Vehicle Weight Rating. This is the maximum allowable weight of the vehicle as seen in the GVWR, plus any towed vehicle. So, if you have a 11,000 pound GCVWR and your vehicle weighs 6,000 fully loaded and ready to take off down the road, the towed load must not exceed 5,000 for a total of 11,000 pounds. You may say “but my truck has a 7,000 pound tow rating. Well, too bad. The GVWR and GCVWR trump whatever the manufacturer states as the tow rating. And yes, sometimes these rating do not jive. When in doubt, always go with the GCVWR and GVWR.

Okay now, here’s an example of how to figure the weights and whether or not you meet the safe specification. First off, you have to get an actual weight of everything involved. This is easy enough. Most any sizable truck stop has a CAT scale where you can get a weight on your rig. Load up as you normally would for a week long camping trip to your favorite spot. Include everything that you would normally take with you. Drive the entire rig down to the CAT scale and pay 6 to 8 bucks or so to have the whole shebang weighed. Most CAT scales are segmented, so that big rigs can get weights on each of their sets of axles. If possible, drop your trailer and get a weight on your truck without your trailer, but with all of the passengers (including yourself) and gear combined. Then go hook up your trailer and repeat the process. Most CAT scales will allow a second weighing for about half price.

I’ll use my previous rig as an example. Here’s what our numbers came out to:

GVWR – 6,650
GCVWR – 11,500
Weight of vehicle loaded (with passengers) – 6,311

That leaves me a maximum tow capacity (based on GCVWR) of 5,189. But guess what? My factory tow rating was 6,100 pounds. If I had stuck a 6,100 pound trailer on the back of my truck, I would have been more than 900 pounds overweight! Note also that the truck, as loaded, was only 339 pounds under it’s GVWR. The tongue weight on my trailer was about 300# which put my Gross Vehicle Weight (of the truck only) at 6,611 pounds, only 39 pounds under max!! Oh, and the trailer? It weighed 3,200 pounds.

Now, do you want to pull a fifth wheel with this same vehicle? Bumper pull trailers usually have about 10% of their weight on the tongue. Fiver’s have around 25% of their weight on the pin. 25% of 3,200 pounds (where can you find a fifth wheel that weighs that little?) is 800 pounds. Add 800 pounds to our Gross Vehicle Weight of 6,311 as shown above and the truck alone tips the scales at 7,111. So with our theoretical Fifth wheel trailer of 3,200 pounds, our truck is overloaded by 461 pounds. You know that that means? That means that we’ll have to leave our mothers-in-law at home. And of course, that is all dependent on finding a fifth wheel that only weights 3,200 pounds.

All of this is an example based upon a Dodge Ram 1500 QC, 4x4, 4.7, 545RFE. The numbers are, no doubt, different for the Hemi. However, the principle remains the same. So the next time someone asks about what they can pull with their truck, point them over here and tell ‘em to run the numbers.

For anyone interested, I hope this post helps keep you and your family safe.
 

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So what kind of gears are we talking about, 3.21, 3.55, or 3.92?
 

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Discussion Starter #3
So what kind of gears are we talking about, 3.21, 3.55, or 3.92?
I get the feeling that you missed the point of my post. It was an example. It applied to a particular truck. Everyone needs to run their own numbers to solve their own tow capability.

That truck, by the way, came with 3:55 gears. I upgraded to 4:56 gears, but that does not alter the GVWR or GCVWR!
 

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Oh,:D Okay sorry about that.:D
 

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but doesnt it alter what you can tow?
I'm not for sure and not starting crap but the same could be from going from 20s to 17s
maybe that the gcvwr are set to the specs of the vehicle and altering the specs would alter what your truck could now tow
 

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Discussion Starter #6
but doesnt it alter what you can tow?
I'm not for sure and not starting crap but the same could be from going from 20s to 17s
maybe that the gcvwr are set to the specs of the vehicle and altering the specs would alter what your truck could now tow
There are different tow ratings for 3:55 versus 3:92 gears. As I mentioned before, power train is part of the equation. However, the sticker on the door is the final authority. Regardless of what you do to the vehicle, it will not change it's legal rating.
 

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got ya
 

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this is great information but maybe I'm just not familiar enough how to work all of the numbers? I have a 2008 Hemi w/ 20" wheels and we're looking to upgrade to a bigger camper, trying to figure out where I get the info to do the math...

Option 1:
Unloaded Vehicle Weight 6750
Hitch Weight (lbs) 945
Gross Vehicle Weight (lbs) 8500
Cargo Carrying Capacity (lbs) 1750

Option 2:
Unloaded Vehicle Weight 7480
Hitch Weight (lbs) 1075
Gross Vehicle Weight (lbs) 9250
Cargo Carrying Capacity (lbs) 1770
 

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Discussion Starter #10
this is great information but maybe I'm just not familiar enough how to work all of the numbers? I have a 2008 Hemi w/ 20" wheels and we're looking to upgrade to a bigger camper, trying to figure out where I get the info to do the math...

Option 1:
Unloaded Vehicle Weight 6750
Hitch Weight (lbs) 945
Gross Vehicle Weight (lbs) 8500
Cargo Carrying Capacity (lbs) 1750

Option 2:
Unloaded Vehicle Weight 7480
Hitch Weight (lbs) 1075
Gross Vehicle Weight (lbs) 9250
Cargo Carrying Capacity (lbs) 1770
You really need to also get the GCVWR (Gross Combined Vehicle Weight Rating) for each of those vehicles. That number should be on the driver's side door jamb.
 

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those are both travel trailers is that something the dealer would provide?
 

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I think you have a great write-up.

But here in Iowa you can buy tags/register your vehicle so you can pull more then the truck is rated for. But it is up to your common sense, if you want to pull more then the truck is rated for. Good luck getting a lawsuit into a court where you didn't break the law.

Summery: the sticker on the door is not the gospel however, following the guidelines is a good idea.
 

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I don't see a GCVWR rated on the sticker on the door - where are you guys finding this?
 

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Discussion Starter #14
those are both travel trailers is that something the dealer would provide?
Then I misread your post. I was assuming that you were giving us the numbers from two different trucks.

When selecting a travel trailer, I personally think it's wise to go by the Gross Vehicle Weight and ignore the supposed weight of the trailer. So, if the trailer is capable of being loaded to 8500 pounds, one should assume that at some point, it actually will be loaded that heavy.
 

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ok, after talking to the dealer, checking the brochure from 2008, we stepped down to a smaller upgrade - looking at this for a trailer.. thoughts?

Unloaded vehicle weight (lbs.) 5,585
Hitch weight (lbs.) 635
Gross vehicle weight (lbs.) 7,500
Cargo carrying capacity (lbs.) 1,915
 

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Discussion Starter #16
ok, after talking to the dealer, checking the brochure from 2008, we stepped down to a smaller upgrade - looking at this for a trailer.. thoughts?

Unloaded vehicle weight (lbs.) 5,585
Hitch weight (lbs.) 635
Gross vehicle weight (lbs.) 7,500
Cargo carrying capacity (lbs.) 1,915
It's impossible to come up with correct values without knowing what your tow vehicle is, how much you're going to load into it, what your family weighs, etc. If you wish to stay within your trucks limits, you HAVE to run the numbers as shown in the example above.
 

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If you have the 3.92 axle ratio you're well under your truck's capability which is approximately 8,500.
 

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Discussion Starter #18
If you have the 3.92 axle ratio you're well under your truck's capability which is approximately 8,500.
Uh, pardon me, but how do you know that? His signature shows an '08 4x4. There is no engine shown. We don't know if it is a v-6, a 4.7 a hemi or a Cummins. Unless I'm missing something in his signature, there is no way to tell him what he can tow without a lot more information.
 

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Mother-in-law

Now, do you want to pull a fifth wheel with this same vehicle? Bumper pull trailers usually have about 10% of their weight on the tongue. Fiver’s have around 25% of their weight on the pin. 25% of 3,200 pounds (where can you find a fifth wheel that weighs that little?) is 800 pounds. Add 800 pounds to our Gross Vehicle Weight of 6,311 as shown above and the truck alone tips the scales at 7,111. So with our theoretical Fifth wheel trailer of 3,200 pounds, our truck is overloaded by 461 pounds. You know that that means? That means that we’ll have to leave our mothers-in-law at home. And of course, that is all dependent on finding a fifth wheel that only weights 3,200 pounds.
safe.
Wow Your mother-in-law weights 461 pounds? Leave her at home!
 
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