Sumo Springs have models that will fit most rigs, they're designed to take the place of air bags on existing air bag mounts, or pay the extra to get the mounting brackets for them.
Personally, they're neat, but require tools to adjust the spring rate and cannot be used to leveling, where as you can do some leveling using air bags.
'92 Dodge W250 "Dually" Power Wagon
'74 KIT 1106 Kamper Slide-in Truck Camper
'06 Heartland Bighorn 3400RL Fifth wheel
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