@ Lorna -
That reminds me of my friend and I at the car wash spraying off his '46 Willy's after a bit of play in the woods. Lots of big chunks of mud and clay up under the fenders etc.
We were just finishing up when a sparkling clean (to us, anyway) grand cherokee pulled in to a nearby wash stall. The funny thing was the decal on their windshield that said "Its a Jeep thing, you wouldn't understand". Sounds like your jeep would prefer the Willy's treatment.