Hmmm.
@Drover is spot on, the ATM is your only real concern. The tare would only ever give some "guidance" of what you van's empty was at some historical point in time when it was built. Your payload is only ever going to be whats left between today's current weigh bridge ticket, and that stamped ATM.
There are conflicting versions of this but stick with me, I reckon mines right. Fact. Jaycos payload on any van is actual weighbridge tare plus a predetermined weight allowance. Fact. Every van is weighed to determine actual tare of each van, and the rest is calculated from that. Fact. The weight allowance is a rounded pre determined figure, dependant on how many axles and if its a bathroom or no bathroom, and that as complex or simple as it gets. Fact Outback or tourer plays no part. To keep it simple, your looking at a dual axle bathroom model and the payload for every base Jayco twin-axle bathroom model built is 475kg. Mine, yours, his, Expanda, Journey, Starcraft, Silverline same same same, Fact every one is a 475kg payload. Each new empty van off the production line van is weighed at the factory, that tare is recorded and the 475kg payload added to that tare to get the ATM. Every new van will have a weighbridge ticket, and that ticket should be found amongst the books and brochures in the van on delivery. Gas bottles are included in the tare, but not the gas inside which is added by the dealer later.
Let's say just for fun your empty factory tare (dry) weight is 2500kg
You take your empty brand new van home and do nothing except fill the water tanks and connect the mains hose, not another single thing more you do. You now "completely" empty the water tanks and disconnect the mains hose and put it back in the garage. The empty weight of van is now 2550kg, 50kg heavier than the factory dry weight and youve done nothing other than briefly fill and then empty the water tanks, and connect and disconnect a hose. There is nothing more you can reasonably remove from it's factory delivered state yet 50kg of your original 475kg payload is now missing. That 50kg is the water in the hot water service, water in the charged plumbing, gas in the gas bottles and residual water in the water tanks that you can never come out. Once you start adding other rudimentary permanent mods or things like such as a power cord, water hose, doorstep for dodgy knees, broom, floor mat, service and warranty books, complimenary dealer couch cushions etc etc your tare quickly becomes more and more a distant memory that (and like any good mother inlaw) you will never ever see it ever again. That's why van tare is an interesting fun fact, but in all other cases utterly useless info.
Its very easy to buy a std van with no options and take it home to add all the very reasonable and common options people do, and then find the van be over its ATM before it's first outing and before you add a sleeping bag, a jumper or a bag of frozen peas. Couple of solar panels, extra battery, diesel or gas heater (although not sure why you'd bother with a gas heater), 2 x 82ltr water tanks, bike rack, gas BBQ .... it doesnt take a lot to burn 475kg of payload, particularly when you're already missing the first 50kg.
There are stories of Jayco, on request, adding a modest addition to their 475kg std payload but don't rely on that because there's many more refusals.
