hey I thought I would have some fun in the water once, in a recent flood we had. It was in the parking though, drove threw. Well, volvo's do float. It about knee high water, the car would rise up from the currents. My Amm survived.

As far as cleaning, I use castrol super cleaner (biodegradble), something like that, it comes in a purple bottle. Spary it on, avoid the paint. Get dirty areas with a nylon brush. Spray off with a water. Avoid the electrical stuff. The trick is start the car when it's wet.

In your case, I would also clean the radiator fins, under body ect. You don't want mud to stay on. And do take out the air and clean it inside, if not done.

ps: how did it handle off road?