slide brand is "Schwintek". noise is not a relay. however, it does seems more present when operating the slide on the battery only. (usually we plug in 1st so slide motors have more volts to work with.) only does it on the largest slide even when camper is quite level. even when making noise the in/out motion seems constant. gear rack underneath looks clean but could use some lubricant. It goes in for service in 2 weeks to repair a "rookie brushed a tree branch" scrape and could be looked at then but if I can figure it out on my own I'd rather do that. thx to anyone offering advice.
A couple of things about the Schwintek slide system.....and you may already know this, but just in case, here goes.
1. The gear rails that are on the side of the slide room should never be lubricated, however, they should be kept clean and free of any debris.
2. When a Schwintek slide is operated, it needs to be done "full stroke" either IN or OUT, and it's a best practice to not stop it in the middle somewhere. If you do have to stop it in the middle, make sure that you follow up with a full in and a full out....or vice versa.
3. When running the slide in or out and the movement stops because the room is all the way in or out, continue to hold the travel direction button down for an additional 3 or 4 seconds. That process helps keep the two motors in sync. There is also a method for "re-syncing" the motors for even travel both in and out, and you can find that online with a google search pretty easily.
And you are correct, the Schwintek system does NOT like low supply voltage, like many other 12VDC appliances/items in the trailer. So make sure that your battery is fully charged before deploying them and or be plugged into shore power so that the Converter/Charger is operating.