The same size as on my 1000kg Troll John. I've decided to stick with the original size when the van was new as a stiffer sidewall tyre may present you with suspension problems.

I think 86T allows you a total load over two tyres of 1060 kg and a speed of 118 mph.

Randa

As above. 86 load rating has a max permissable load of 1060Kg but a max recommended of 954kg.
I'm guessing your van is actually a 2014 320, but I don't know if it has the standard axle load of 900kg or the optional 1050kg.
If yours is the 900kg then stick with what you have. If you have the 1050kg axle then you need to go up a little. As Roger suggets, if you go up to much then your suspension suffers as the tyre wall provides some of this suspension. Rule of thumb is do not exceed your max axle load by more than 10%.
Our vans are easily capable of running on car tyres and as a far wider range are available that is what I would stick with.

Colin

The problem I've found is that tyres of that size and a rating of 86T are as big as it gets and the next rating up which is readily available is a van rating which gives you over 1200kg total for the two wheels.

That's why I've kept to the 86T as our van was always rated at 1000kg so the tyres I use are only 6% over the max axle load. The other thing to note is that this tyre size and load rating has a fair range of max. tyre pressures dependant on the make of tyre.

I always have to look for a tyre that'll give me more than 3 bar max pressure as Hymer now recommend that they are run at 3 bar. I run ours at about 40psi (2.75bar).

Randa

I would be happier with a slightly higher rating but a quick search shows 93 [1170kg recommended and 1300kg permissible ] seems tto be the next load rating readily available.
I think I would phone around a few trye outlets to see what is available but push that you do not want commercial or reinforced tyres.A 91 load rating would be perfect.

Colin