We currently have a 2007 Jayco Seneca 33ss (Chevy C5500) and as with most super "C's" the generator is located about 3 ft behind the driver side drive wheels. Just the right distance to get all the mud, rocks and water thrown up into the open grille area of the generator.
SO......... on a very rainy drive to Florida this fall, we "lost" our generator.
Per the great folks at North Florida Welding Supply in lake City, who rebuilt it, we had a bunch of rocks and mud in the intake and it literally ground her to a halt..........
My DIY fix was to add an 8" rubber skirt (floor mat mat'l) around the front of the generator, AND to add 10" of poly rubber mud flap material to the existing rear mud flaps. They are now 6" off the pavement.
Our latest trip down a wet gravel road in Colorado has proven to me that our "fix" works, as there is mud on the generator skirt, but not nearly as much as there used to be.
Thought I would pass along our "fix" , as so many threads are problems and not solutions.
Mike in Colorado