It does sound a little like the old throw parts at it game, but most of the time these creeps (not referring to your shop tech
) are solenoid-caused. Admittedly up front, I have not actually messed with the solenoid manifold personally, so the following is based on what I've read online and in some manuals, interaction with HWH, and experience as a small, relatively unversed dealer's shop replaced some under warranty on our coach 10 years ago.
Some people have managed to remove and clean or totally replace the O-rings on individual solenoids. They can age like other rubbery products if let go for very long without use so they dry out and crack enough to allow leakage. They also can fail to seat if a particle of debris that's contaminated the fluid jams around the O-ring. It's a good reason to be exceptionally careful when opening the tank fill or removing and replacing solenoids or line fittings - a thorough cleaning around such things beforehand is essential, but it can be hard to keep things pristine in often snug locations. That goes for the port the solenoids come out of.
One needs to be sure to deal with the correct solenoids also. It is likely you have at least 6 on the manifold, 2 for each hydraulic slide on your Bayshore IV (4 slides - 1 of which may or may not be a non-hydraulic, under-bed electric), and perhaps 2 more solenoids for another hydraulic device. Each slideout will have one "In" and one "Out" solenoid. As I recall, solenoids 1 & 2 are for the streetside front, and then in sequence counterclockwise around the coach, skipping the bed slide if it's electric. I've often thought that picking out the right solenoid might simply entail one helper operating the switches while another held a stethoscope or screwdriver to each solenoid in the manifold, listening for its activation.
When my curbside front was fixed under warranty, HWH recommended replacing both its solenoids; at the time that was the practice - replace the set even though perhaps only one solenoid was haywire. As I took it, the "In" solenoid was letting fluid by, releasing pressure that would've otherwise held the slide in, and that allowed it to come out a foot on the freeway. Nowdays I hear HWH is okay with replacing only the one misbehaving solenoid of the pair.
Yours doesn't seem to quite fit this scenario, Tommy, but often people have an issue with a slide creeping out a half-inch or more while parked in storage, for example. Mine does it occasionally, and even once one creeped an inch or two back in while in extended mode at a campsite. I've found that it's probably the very minorest of O-ring leak - perhaps just a speck of debris in the fluid, stuck on a seal surface and temporarily allowing seepage. Most people seem to think when this happens that a solenoid needs replacing, but I've simply hit the out switch for 2 seconds, then all the way back in, and it stays put after that; that austere action apparently flushes the offending particle free of the seal.
-Joel
