You should be okay with the retraction times mentioned in the OP. I spray my jack pistons about once every 3 months. I do not us WD40. I use Solder Seal Penetrating Oil. It is in a spray can at Lowe's. Just spray the pistons, do not wipe them down.
Consider trying this when breaking camp.
1. Start the engine.
2. Store the jacks.
3. While the jacks are storing themselves, do your final walk around.
4. If you return to the cockpit and the warning buzzer is still sounding, the pistons need to be sprayed.
Per an earlier post, check the springs. If they are straight to the end, get new springs.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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