mud stuck like concrete

get it off. put the sprinkler under your car and move it back about every 10-15 minutes to get every part underneath. then put on some old clothes and take it to the carlovers and get under it down and dirty blowing out as much as you can. Then back home and get to it with the hose which has a higher water flow than a high pressure washer to finish things off. Pay particular attention to places like on top of the tranny and transfer case as well as around the wheels brakes and suspension. Check the chasis rails as well as mud lurks in there and you thread the hose through the holes in the chasis and feed it back and forward to get this mud out.
One reason minesite vehicles are fubar after 100k is because they are coated in mud most of the time
There is no easy way to do the job properly and it is the reason I do my best to avoid driving in muddy conditions.

The sprinkler works well, except if you're on water restrictions... We recycle our water at work so I do it there. I use one of those Pope units, orange with 3 chrome arms & multiple outlets, seems to reach everywhere.

I just use a $10.00 soaker hose from bunnings, get the long one and you can run it backwards and forwards a couple of times under the vehicle and I let it run for about an hour on the lawn that way your watering and top soiling the lawn at the same time. Regards Vitara

That outback mud, good stuff ehhh!

The best thing is a nice flowing river with a concrete causeway that is deep enough to reach the floor of the car etc. Here in Broken Hill when it does rain, the streets are the stormwater drains and it provides good opportunity for cleaning the underside of the car.

A couple of years ago my lovely wife bought me a medium sized high pressure cleaner for my birthday.

Usually I put the car up on the ramps so I can get at it good and give it some with the high pressure. Back and forwards round and round making sure I hit every part of the car from a couple of different angles. Same thing on the camper.

Duncs