I am the same as Jim and millions of others who winter in Florida and have their jacks down for months at a time. I use Lithium Grease on my jack pistons. It can be purchased at Lowes or Home Depot. Spray, exercise the jacks every month and wipe off the excess that will be at the bottom of the piston next to the jack pad.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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