There are 3 main factors with how much you can tow. While it all seems simple, digging in makes it a little less clear. Yes, it’s easy to look at the simple rating numbers, but that can be slightly misleading. As with many things, the confusion comes when looking at the details.
Most people towing a trailer are well within the capacity of their tow vehicle. For them, this discussion is moot. On the other hand, there are many situations where the trailer exceeds the “limits”. Those are the ones to avoid. Of course, things don’t suddenly fall apart when you go one pound over, but we think it’s a good idea to know.
So, the easy thing is to look up the manufacturers published number, then stay well under it. Check the links (near the bottom) for VIN look-up calculators. That will tell you the vehicle specs.
Then, if you want to think more deeply, read on. We’ll start with the VIN look-up, id stickers, or owners manual, then dig into what the numbers mean. We’ll also look at other factors. Hopefully we can offer a little more knowledge about how much you can tow.
The 3 main factors are: 1) Load limits of the Tow Vehicle; 2) Load limits of the Components; 3) Legal limits. We’ll mix these together in the discussion below.
Towing Limits
As we look at capacity, always remember the lowest number wins. We can have a lot of really beefy, strong parts, but the item with the lowest capacity is the one that determines how much you can tow. Sometimes that’s the vehicle, sometimes it’s the hitch or some other part. Sometimes, it’s having trailer brakes or not.
Secondly, numbers from the vehicle manufacturer are limits for what engineering says is safe. If you’re within those limits, things should be fine. Outside of those limits, you’re adding risk — the consequences can be severe. (That said, out of necessity, I have towed a 32′ 5th-wheel with a Ford Ranger. It violated every rule in the book. I also pulled a 20′ flat bed with an ’83 VW Rabbit. It can be done, but that doesn’t mean it’s smart.) Please realize that liability for failure falls entirely on you, if you’re outrageously outside the limits (like in these 2 examples). Furthermore, some insurance will not pay in those circumstances, or if they do, they’ll drop you immediately after.
We’re not talking about what you can get away with, we’re talking about your quality of life, and/or that of your equipment. Perhaps the quality of other lives. Having the wrong thing happen when you’re pushing your luck will make a very bad day. Enough said.
How Much Does The Manufacturer Say You Can Tow?
While every vehicle has ratings for weight, not all should tow a trailer. There are 3 ways to find the weight ratings for your vehicle. First, there is a tag in the door jam of the drivers door. This photo shows it on a Ford F-150. The photo above shows one for a Jeep.
Second, the vehicle owners manual will have information about towing.
Third, use a VIN calculator to look-up your exact vehicle specs. Find the VIN (Vehicle Identification Number) on the tag on the door jam. The VIN is also on a tag you can see from outside the car, through the windshield, at the drivers side lower corner. Use that VIN to look up tons of stuff on your car, like the trailer tow ratings, CarFAX vehicle history, and more.
1. GVW or GVWR
Gross Vehicle Weight / Rating
Gross — meaning overall, whole, total, or complete.
Vehicle — meaning the tow vehicle itself, with everything in it (passengers and cargo), but not a trailer.
This can be a little confusing, because GVWR includes the trailer tongue weight just like cargo.
2. GAWR
Gross Axle Weight Rating — is for each axle. You’ll see it listed separate for Front and Rear. Though hard to measure, you should not exceed the numbers for either axle. When pulling a trailer, Gross Axle Weight includes tongue weight, but not the rest of the trailer.
The key here, the axle dominates. If you have a lot of weight in the back, you can overload the G(Axle)WR while still within G(Vehicle)WR.
3. GCVW
Gross Combined Vehicle Weight. As you might guess, GCVW (also GCVWR – Gross Combined Vehicle Weight Rating) includes the weight of the vehicle, trailer, passengers, and all cargo. Basically, everything as it goes down the road. In other words, if you have a lot of cargo or people in the tow vehicle, then your trailer must be lighter.
I personally find the GCVW numbers by themselves a little difficult to work with. You really have to put them together with other numbers to make sense of them.
4. GTW
Gross Trailer Weight. Each vehicle has a rating or maximum, total trailer weight. I say every vehicle, but some vehicles strictly forbid trailer towing. In effect, their max trailer weight is Zero.
Assuming your vehicle is rated for towing a trailer, you will find the towing capacity in a few places. Start with the owners manual if you have it, or online. There is probably a section on “Recommended Towing Weight.”
Next, the manufacturers website. This image comes from a Ford publication for F-150 trucks. There are a lot of options that change capacity, so it takes the 2-page PDF to show them all. There are similar publications for most vehicles.
Another place to look is the capacities sticker that appears on the drivers side door jam. (See above.) It won’t be complete with the trailer tow info, but it’s a start.
Best, is with the VIN look up. See below. The numbers are specific to your vehicle as it came from the factory. Mods you do — like lift kits, or engine, etc. — are not included.
5. Tongue Weight
Unless otherwise stated, the numbers for GTW assume a tongue weight. This is where things can get confusing. Every vehicle has a rating for maximum tongue weight, but tongue weight is part of the Axle load, and the Gross Vehicle Weight. So, adding a trailer changes how much you can put in the vehicle. Or, the other way, how much you can tow changes with how much cargo you carry.
Normally, info on tongue weight is in the same places as GTW. However, some manufacturers just say tongue weight is 10% of the total trailer weight. That’s the easy way out for them, but it puts us in a little bind.
Though we agree 10% works, it’s on the light side of 10%-15% as recommended. We usually suggest a little more than 10% because a light tongue can make a squirrely trailer. Remember this video?
What Drives These “Gross” Numbers?
There is a bunch within the numbers. I don’t pretend to know a whole lot about it, but here are some “directionally correct” things to consider.
First, vehicle structure. To tow a lot, the vehicle needs significant structure, and mass. Dynamics of towing are not trivial, so the vehicle must be built to handle it. This includes frame, hitch, axles, wheels . . . the lot.
Second, suspension. If the suspension is soft, the vehicle rides nicer (generally), but can’t carry or tow as much. Sometimes a load distribution hitch will help, but not completely. Have you ever noticed the tow capacity is sometimes more with a weight distribution hitch? (Not always because of other factors.)
Third, brakes. The tow vehicle brakes can limit how much you can tow. The brakes take more with a trailer, even if the trailer has good brakes. An example is braking in a corner. Read this article about when your trailer should have brakes.
Fourth, overhang. For bumper pull trailers, the distance from the rear axle to the hitch is overhang. The longer that gets, the less the vehicle can tow. This includes popular drawbar extensions. That “Lever” from the axle to the hitch allows the trailer to wag the tow vehicle if things get wonky. You can see that in trailer tow capacity of an extended van compared to a standard version of the same van.
Fifth, length of the tow vehicle. This one has a double edge because longer vehicles typically weigh more, and if the axles don’t change, tow capacity goes down. However, in a theoretical sense, there is more stability with a longer vehicle (distance from front axle to rear axle).
There are more, but we’ll leave it at that for now.
What Do Your Components Say You Can Tow?
Since the weakest link determines max capacity, we need to look at the whole system. First, the hitch. If it came from the factory with the vehicle, then it’s in the specs above. If it’s an add-on, check it’s weight rating. Some of this is absorbed in the trailer hitch class rating.
Next, the receiver, ball, or whatever you use to attach the trailer. They all have a weight or load rating, and usually it’s right on the parts. Here are a few images showing ball ratings, as well as drawbar ratings for example.
Capacity of every piece in the string must be higher than the actual trailer + load. This includes the hitch, axles and parts of the trailer. You need to know the ratings because they dictate how much you can tow with them.
Finally, there are the pieces we don’t often consider — like the tow vehicle tire ratings, similar to the trailer tire ratings. Often these ratings are dependent on the tire pressure, so when you tow, pump up the tires for the load you wish to carry.
Some Towing Misnomers
Engine. When talking about tow capacity, it’s easy to point to the engine. While more power and more torque do make towing more pleasant, it doesn’t really raise the tow limits. It will move the load better, for sure, yet it’s a lower factor in tow capacity. There are too many other factors.
Transmission. Can you tow more with an automatic transmission? While it’s definitely easier, it’s a warp of the truth. Having worked in a transmission division, Yes, manufacturers de-rate manual transmissions — to protect the driving experience. Here are 2 big factors:
- The torque converter of an automatic helps launch and maneuvering. Manual transmissions don’t have that, so they are perceived as harder to drive, especially with a heavy trailer. Also, many manual transmission clutches are not made for heavy towing. Stout manual clutches are not as drivable for an empty vehicle, so manufacturers don’t like to sell them.
- Cooling. You can put a bigger cooler on an automatic, because it has a pump. Manual transmissions create much less heat, but without a pump, they are harder to cool. And, the clutch has only air cooling. (Think about less experienced drivers. Can you smell the “burning” clutch?)
Final Drive. For the same reasons as engines, a lower final drive ratio doesn’t really change towing limits. Sure, it’s nicer for towing, but it’s only a minor change in capacity. (Final drive is the gears in the axle. A bigger number, 3.73 to 4.10, makes a lower gear ratio.)
4 x 4. There are various stories about how 4-wheel-drive improves or degrades towing capacity. It’s a plus and minus. Don’t worry about the stories. If you need a 4×4, then get it. If you prefer a vehicle without, that works too. Just stay within the manufacturers limits.
Limits on How Much to Tow
The limits are there to keep us safe, and they’re pretty easy to follow. Laws now control the requirements, so just add it all up to know the towing limits. If you worry, it doesn’t hurt to drive across a scale to find out the weight on each axle. To me, the GAWR (Axle Weight Rating) is the most important. Well, that and the component ratings, and Tongue weight.
Some things that modify the limits include live loads (horses, cows, lamas, etc.), high profile loads, and high center of gravity loads. As far as I know, there are no hard rules for these limit changers, but it’s smart to down grade if these are your load. High profile and high center of gravity loads add stress to the towing. Live loads will shift, and that adds load stress — not to mention the seriousness of a mishap with a live load.
Laws are the last limiter. Just check what your local jurisdiction says. For instance, in Colorado, without trailer brakes, the max possible GTW is 3000 lbs. Doesn’t matter the actual trailer size or capacity.
The point here is to be smart. I’ve done stupid, and mostly I got away with it. Not always, however, so I hope I’ve learned along the way. Here is a good list of Trailer Towing Tips to go along with towing smarter.
VIN Lookup Calculators
The easiest way to get good information about how much trailer your vehicle can tow is to look it up with a VIN Calculator. Yes, most are free, and most have tons of advertising with them, but the process is pretty straightforward with accurate factory results. You might have to modify the numbers a little if you’ve done any vehicle mods.
Here are a few links to the VIN Lookup calculators for answering the question: How Much Trailer Can I Tow?
- Camping World has a good VIN Lookup here.
- These guys have a nice page that links to some manufacturer specific data. Freemont motors.
- Most manufacturer website also have specific info. Google search by their name and “Trailer Towing Capacity”.
Good Luck with all your Towing !!!
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