A bit undecided on what pressure to have the tyres when towing a Caravan. Nose weight of van around 80-90Kg and weight around 1650Kg. Car will have two adults in the front and lightly loaded in the load area with probably around 50kg of items. Car is an L405 2020 running on 21" tyres, current pressures are the indicated 35/38psi which shows 4 people in the car on the label.

Would it be necessary to increase the pressures right up to the heavy load levels or somewhere between the two levels?

Try in between and then full load. I didn't change pressures when towing with my D3, it was fine. My audi though..had to whack all 4 up to max load pressures to get it feeling OK. Yet to try the l322 but I'll be trying mid point then full load

We're 2 adults, 2 kids 9 and 12, 2 staffys and normally decent load in the boot, same nose weight as you

L322 not L405 but… Cabin loaded with car bits, fully fuelled. Trailer with small track car but also tools and spare wheels. PSI was set at mid point when cold. However when warm had increased to closer to full load values. Was perfect on 220-mile round trip. No wandering or “bouncing” at all.

No caravan experience, but with the trailer my rear tyres are inflated to 42psi, which I think is what LR recommend and has been fine. Fronts stay at normal 34psi. Only Range Rovers since 1988

Just to add to this, towed mine a couple of times now, pretty much fully loaded on last trip.

Caravan 1560kg

Kept tyre pressures standard all round and its been spot on 👌 3.6 TDV8 Java Black

I guess I looked at this differently - I never changed my rear tyre pressures when towing a big 2000kg+ caravan... the additional downward weight on the tow ball was only an extra 98kg so as long as the car wasn't unusually/fully loaded I didn't think it would make much difference? You'd hardly know the caravan was there so I just stuck with that. In my mind it was more effort required in moving it forward, not taking on loads of extra weight to the rear.

Sure someone will be along to explain the error of my ways shortly  FFRR SDV8 Autobiography

Tyre pressures are determined by temperature...

Easy way to check if your pressures are correct...

Measure the pressure with the tyre cold, drive at motorway speeds for 20+ miles, stop and immediately check the pressures, they should be 4psi higher than when cold...

Adjust the pressures until you arrive at 4psi higher cold to hot...  Pete
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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
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James,
That is what I thought until after crossing the QE2 bridge my towing plug came loose, which then disconnected the ATC on the caravan, It was very windy and made the caravan very unstable, I was keeping below the speed limit as it was windy.
As such I looked at what I have in the caravan and managed to take out 150kg, including 1 gas bottle.
Although I have about 300kg I can load on top of the caravan's weight, I have to add up the motor movers, E&P levelling system, 310w solar, and inverter.
On top of that personal bits and bobs.

There is plenty of information on an overweight caravan on youtube.
We are lucky that we do not have roadside police/Transport people to check us, they seem to be only interested in HGV.
We all need to be responsible road users. 2017 SDV8 4.4 silicon silver AB
2012 TDV8 4.4 Stornaway Grey AB
2011 TDV8 4.4 Buckingham Blue
2012 VW V6 3.0 Tougreg

Completely agree on heavy caravans, when I sold mine and emptied it I was quite shocked at what had slowly accumulated over the years and was probably taking the caravan over its plated weight. But (unless the caravan is loaded incorrectly) that extra weight still doesn't sit on the tow ball as a downward, additional weight on the rear of the vehicle does it? It is 'rolling mass' pulled by the vehicle, but the nose weight is controllable.

I'm very glad the scary situation on the bridge didn't end up in disaster - must have been terrifying  FFRR SDV8 Autobiography

I only mentioned my experience when the ATC was turned off to inform other people of the dangers of not having the correct setup to start with, tyres, car to caravan/trailer weight, etc. as it soon becomes a big problem. 2017 SDV8 4.4 silicon silver AB
2012 TDV8 4.4 Stornaway Grey AB
2011 TDV8 4.4 Buckingham Blue
2012 VW V6 3.0 Tougreg

Tinman wrote:

We are lucky that we do not have roadside police/Transport people to check us, they seem to be only interested in HGV.

It’s surprising what small changes can make a big difference.

Getting the nose weight right is an important thing. I was surprised when I checked our Bailey for a trip to France last year. Because it has a big rear storage under the bed I had put quite a lot of junk in there and while I was ok weight wise it meant I had next to no weight on the nose. I moved a few things up front, and moved my cadac from over the axle to a front locker and it’s now at 95kg. Only move a few chairs and the cadac.

I had done the leg to Folkestone like this and it was a bit of a handful, which prompted me to check. Much much better once loaded and balanced properly! There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2010 LR D4 Commercial 2.7 TDV6