Lets talk about Tow Ball Mass (The Most IMPORTANT Caravan Weight)

G'day Vanfam and welcome back to another video. In this video, were taking a deep dive into Tow Ball Mass (TBM). We explain why this is the most important caravan weight and run some tests to see if cheap tow ball scales work and what impact raising and lowering your Tow Ball Height will have on your Tow Ball Mass.
Hope you get something out of the video.
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[@Morris-Minor-1953]

As with any spring based weighing device you should lightly bounce the draw bar and then take a reading as there is friction within the spring tube. You will find it will show a higher reading (actual weight) after the light bounce. Try it yourself then check it against your pro gear. Mine ended up within 2 kg of a pro weighing.

[@SvedosTrippin]

Excellent advice, I will pin this one so hopefully others will find it. Thanks for commenting 🙂

[@GoYourOwnWay49]

Great video, Brett! Thanks for sharing and breaking down the importance of TBM so clearly. The tests on the tow ball scales and height adjustments were super useful and insightful…definitely some key takeaways for safe caravanning. Cheers for the top-notch info! Take care and stay safe. Kind regards, Corrie

[@SvedosTrippin]

Cheers Corrie, glad to hear you enjoyed the video.

[@AdventuringPals]

Hi mate. Good effort on the video. I would have liked to see you measure with both scales at the same height to see exactly how accurate or inaccurate these cheaper DIY scales really are. I’ve used one since I stared caravanning but now I’m thinking it may have been pointless if they are so far out.

[@SvedosTrippin]

yeah, I wish I had of thought of the fix on the day and not while editing, but I measured at 50mm drop and was down 6kg so add another 6kg and you have the total error. Thanks for watching.

[@desparky]

What type of dual axle suspension did the New Age have? I'm guessing it isn't a load sharing design which I assume should act like a single pivot point at that small of an angle change. The el-cheapo scale requires bouncing to overcome static friction, however I wouldn't expect the same accuracy as a calibrated load cell. You also have to chock the van wheels and ensure no sideways load on the sliding mechanism. When moving items around to reduce TBM, avoid moving any mass to the rear of the axle. I often see people move things like bike racks from the drawbar to the rear of the van which only worsens the pendulum sway effect.

[@aussie-all-the-way]

Never, I repeat never, use one of those spring loaded scales with a DO35. I've seen a guy have his eye socket smashed when the hitch pivoted & with 200kg pressure being released the scales took off like a missile.

[@lindsay6529]

Just tried the pop up link "play on you tv". How good is that 😂

[@allanbarton5888]

Hi When you looked at cheap towball you said 195 kg At the you said 190 kg thus increasing the difference between your accurate scales and the cheaper ones Please be consistent in your measurements Cheers

[@SvedosTrippin]

my mistake, sorry for the error.

[@damienwilkie41]

Hi mate . Good informative video, i just want to touch on load sharing duel axel suspension, does TBM work the same as a single axle van in this case ?

[@gavingamston1693]

Not sure why you did not just put a 50 mm block under cheap version so when lowered it came to correct height. Specially when you pack your equipment being precise 5mm.

[@SvedosTrippin]

@gavingamston1693 hey mate, the issue is the pole depresses about 65mm when it takes up the weight of the TBM. In Hind sight, I could of raised the tow ball 65mm before lowering it onto the pole scale but I diddnt think of this on the day, just as an after thought.

[@MegaRich7]

That's the opposite of what you said would happen if the van sat lower. Also when you are measuring your travelling hitch height , I'm guessing you are measuring straight up and down. When you were measuring with you redthingy mabob, you were measuring at an angle due to the wide baseplate. Adjacent versus Hypotenuse. So the difference of 5mm wouldn't have made enough of a difference.

[@chrishoffman8619]

Now I'm definitely worried about getting weighed!! 😂 Do you sell tow vehicles on your website by any chance?

[@SvedosTrippin]

hahaha.

[@garybrown1526]

Hi Brett, another great informative video. Just wondering what your ATM is if rule of thumb is 10%, isn’t 206.5kg too light?? Shouldn’t your TBM be closer to 280-300kg? I’ve had 2 different single axle vans, both ATM 3000kg. They both came in close 350kg TBM but I’ve recently moved one water tank on our latest van to behind the axle and it registers about 310kg. I’m happier with the 310 as it rides better and puts less wright on vehicle axle. Your thoughts on this? Thanks mate

[@SvedosTrippin]

Hey Gary, thanks glad you have enjoyed the video. In this scenario, I had no water in my water tanks and our camping gear (tables and chairs), boat motor and and battery which all sit forward of the axle were all out of the van, this is why my TBM was lighter. My TBM usually sits around 240kg and the van at 2680. I also prefer to run my TBM on the lighter side to help with Axle weights and we find our setup very stable. 350kg on a 3 ton van is certainly on the heavier side and will be causing an increased load on your rear axles, the changes you made seem to have helped with that and its good that its riding better.

[@mho6540]

Take it back to the shop with that receipt and info from the video and get the money back!! 😉

[@SvedosTrippin]

hahaha it would be a long drive back to the shop. at $50 I think I got what I paid for.

[@mho6540]

@SvedosTrippin should have gone for Christmas 😉😛 We're missing you guys! - the Falcon

[@tanithtam4712]

How to connect you to start a business cooperation?

[@SvedosTrippin]

Hi there. There are contact us forms on our website www.svedos.com.au

[@David-f1y2z]

I bought a towsafe tow ball scale , I think it’s rubbish and going to put in in the bin . It seems to stick when you lower it , it goes down to around 190 ks but if you push on the drawbar it’ll go down to 250 and not spring back up . Tried spraying with silicone spray but makes no difference . I’m going to get professional weighed .

[@crusty181]

I do enjoy your content but this advice is misleading. The 10% ATM/TBM is a naive social media inspired myth, and potentially dangerous advice. There is no basis for this claim in engineering or reality. Many other factors impact towing stability and forcing a arbitrary percentage to the TBM isnt one of them. Many vans at this mythical 10% tow like dogs, and many at 5% tow perfectly. Anything that helps to simplify peoples ability to know their own rig and tow safely is great and the service that mobile weight operators provide is a step closer to a safer travel environment for us all ... but sticking to the facts is vital.

[@SvedosTrippin]

Hey there, thanks for watching and for taking the time to share your thoughts! Tow ball mass (TBM) percentage is definitely a topic that sparks a lot of debate, and I appreciate your perspective. Here's what I know: The 10% TBM guideline is not a "myth" but is in fact referenced in several Australian vehicle manufacturers' manuals. These recommendations are made by engineers who design vehicles for Australian conditions and are based on their testing and specifications. While it’s true that towing setups in Europe often have lighter TBM percentages, the differences in vehicle design, caravan construction, and road conditions between Europe and Australia mean those recommendations don’t always translate well here. From my experience in working with clients, I’ve observed a clear trend: several people who reached out to me due to caravan sway had TBM percentages around 7%. After increasing their TBM percentage closer to 10%, they reported significant improvements in stability. That said, I’ve also seen setups at 7% that tow without issues-at least for now. This suggests that factors such as caravan design, weight distribution, and suspension systems also play a role in towing stability. While there’s no single “magic number” that guarantees stability for every setup, increasing the TBM percentage in cases where it is low has proven to be effective and is unlikely to worsen stability. I think that makes it sound advice when taken in the context of the broader picture of towing safety. I agree with your point that simplifying the process for people to understand their own rigs and tow safely is critical. That’s what motivates me to provide content like this and offer mobile weighing services-it’s all about improving safety on the road for everyone. Thanks again for sharing your thoughts. Discussions like this help us all learn and improve!

[@crusty181]

@SvedosTrippin I dont discount the importance of knowing the specified and combine weights but thats limited to remaning within legislative requirements, how to stay within their specific and combined and thats where in should end. Stating how those weights and baseless theories will apply in a dynamic reality is a very different animal and both wildly misleading and dangerous. Many of the 100s of caravan and chassis 'engineers' arent building quite the theoretically balanced units that the rigorously tested vehicles that those engineers might be hoping are being hooked up. Any automotive engineer who states an arbitary TBM percentive will apply to any unknown, unspecified, untested loaded up and attached to a car is a fool. Caravan and chassis designs theoretical only, untested and many are death traps that tow like dogs The only method is dynamic testing which everyone who values their family should and would do, and that isnt so difficult. Stationary arbitary numbers in a box have zero correlation to a dynamic articulated 5 to 9 ton dynamic load travelling at 100kph. With respect youd have to be more than a little naive to think safety is getting some arbitary numbers to fit in a box while disregarding unknown and untested variables. Some caravans that fit in the provided boxes tow like dogs, and some caravans that are well outside the provided boxes are stable. Weight is very important only from legal perspective, adjusting the TBM based on an arbitary unfounded percentage without dynamic testing while disregarding all other variables is nuts. Its a very real possibility a stable caravan outside the 10% could become unstable by modifying load bringing it within 10%. The point is you dont and cant know. My point is you provide a valuable service no doubt, but youre personally treading on dangerous ground recommending changes you cant factually support and have no idea how they will play out. Be both mindful and careful for your and my sakes. 👍

[@geoffbuys5838]

​@@crusty181Read your comment so in your experience what is the best way to estimate TBM dynamically?