NOT ENOUGH AIR FILTER

[cdfurst]

I have a 2010 CM871 650HP with 83k on the odometer (yep it's a motor coach), demanned, I've only put 20k on it since purchase and only 3k on the deman. When I bought it, first thing I noticed was the Filter Minder was in the red, so first thing I did was replace the air filter. With a brand new filter, it still jumped into the red. I replaced the filter again, SAME THING. Is this 650 beast sucking so much air it doesn't have enough filter surface. Did a little research and as far I can tell I have the largest filter available. Anyone else having this problem? I think at this point, I'm looking at adding another filter to the mix. Gonna be tough tho, not much space in there.