Towing witha P38

I have recently bought my P38
First one and love it (So far)

The main reason i got it was to tow my caravan.

Now i need some advice.

I did tow it with my company car a 57 plate 3.2 D Shogun.

Pulled well but it had no air suspention.

This will be the first vehicle with this fitted and i am a bit unsure of the best setting to have it on.

The van is a twin wheeler Elddis Crusader With a weight of 1900kg.

The book says have it on standard setting But says nothin about changing the tyre pressures.

Anyone have any ideas on this

Is standard air setting correct?
Shouldi just keep to standard tyre pressure?
by the way the tryes are 255/65 R16.

thanks

Keep the tyre pressures standard and you will be fine
Remember to isolate the air suspension using the switch on the dash so it doesn't try to drop to motorway mode over 55 mph in case this affects the handling of the caravan