Caravan Weights You Need to Know: Gvm, Tare Weight, Towball Weight, Cvm

Caravan weights are a vital piece of information to know if you are looking at buying or renting a caravan. It’s easy to hear all the terms like Aggregate Trailer Mass (ATM), Gross Trailer Mass (GTM), Tare Mass and Towball Mass and get confused quite quickly. But after reading this blog you should have a thorough understanding of what all this terminology means and be able to tow a caravan safely. We have broken all the caravan weights for you and also have a video with Ben from SundownerRV giving us the inside tips and tricks on the caravan weights that are important It’s not as simple as just hooking the caravan up to the car and driving off but after reading this blog it will be.

What can your tow vehicle tow?

The first place to look for an understanding of the caravan weights is in your towing vehicle to see what your car is rated to tow. This information can be found in your car manual (on the internet nowadays as well). This will give you all the information you need to make sure you are able to tow a specifc caravan.

The next step is figuring out the various weight measurements of the particular caravan. All caravans post-1985 have a VIN plate. On the VIN plate, all the caravan weights and dimensions are specified.

Tare weight

The TARE weight is what the caravan weighs as supplied by the dealer. This is the total weight but not fully loaded. This is with no water in the tanks, no gas in the in the cylinders or any personal things. It also doesn’t include the added accessories like the awning, air-conditioning and is an important measurement to know to figure out how many extras you are actually allowed!

If you add the accessories weight as well as two water tanks and gas tanks it can quickly add up. It pays to know how much-added weight you are carrying on top of the tare weight. Once you have added your accessories it can already amount to 100s of kgs so this is one you need to be aware of when buying a caravan.

ATM (Aggregate Trailer Mass)

The next important weight you need to know is the ATM (aggregate trailer mass). The aggregate trailer mass is also sometimes called the GVM  (depends which expert you are talking to)

In order to have a safe and comfortable journey, the ATM is one of the most important. It’s a simple one to measure as its the absolute total weight your caravan can weigh. It includes absolutely everything inside and out as it sits in your driveway before you head off. The ATM is one of the most important to check before you head off on your holiday.

Towball Weight

The tow ball weight or ball weight as its sometimes called is the downward pressure that the caravan hitch places on the tow ball of the car.

This greatly affects how the caravan fits behind the car and whether it will sway etc so its vital that this is taken into account.

This should be on the caravan VIN plate but if it is not stated there you can find it subtracting the GTM (gross trailer mass) from the ATM fo figure it out.

CVM (Combined Vehicle Mass)

The last weight that one should know before taking off in their caravan is the CVM (Combined vehicle mass). This is the total weight of the car and caravan combined which can be found in the cars owners manual. It means sometimes you won’t be able to tow the full weight of the caravan if your car is fully loaded as well. You might not be able to take the kids (I know some of you wouldn’t complain about that ;))! So it makes sense to check or you could leave the kids at home? Add these together and you will find out if your legal or not.

It’s vital to know your caravan weights and know what you can tow before you set off, we hope this little guide is helpful.