The 3171 is the one of the longest coaches in FR Class C line and I believe it has the most "tail" behind the rear axle. This makes it hard coming off of just about any curb regardless how carefully you drive off. My coach came installed with the Firestone air bags on the rear axle. I added the Air Lift WirelessAir ( https://www.airliftcompany.com/shop/72000/
) so I can adjust the air bag pressure (and height) without leaving the drivers seat. When I had the rear bags at 80 psi or more, I occasional experienced the front suspension bottom out. I purchased Air Lift bags for my front coil springs but then wanted the same wireless feature for adjusting on the fly. Unfortunately that meant buying another WirelessAir system since the remote doesn't control two axles. A good chunk of change latter I am pleased with the setup.
So when I know I am going to be pulling into a fuel station I just bump up the bag pressures to lift the coach some to clear and then bump them back down when I get back on the road.
The other cool thing is to be able to dump the pressures from all the bags before using my hydraulic levelers since you're not supposed to lift the coach with air pressure in the bags.
It's not foolproof since some steep curbs still cause my skids at the hitch to sometimes drag. I already bought skid wheels but my skids are configured a bit different so I might have to weld the skid wheel plate on.