[Richard]

OK, this mystery is solved. On my coach, the salon slide does not have a synchronizing cylinder as the HWH literature indicates. I found a slide part number AP10816 which shows that the slide has an anti racking valve instead of the synchronizing cylinder.

I am posting this for anyone dealing with a slide with this part number.

The anti racking valve is mounted differently than anything I could find in the HWH literature. The valve resides in the basement ceiling, middle of the slideout, on the driver side. The slide must be all the way out and the floor up to see it. I had to remove the ceiling tiles in that area to gain access. I was able to correct most of the racking by adjusting on this valve.

The second thing to be aware, that is different from the HWH literature, is that Newell ran steel tubing for the hydraulics and only used shorter pieces of hose to connect the tubing to the hydraulic cylinders. I make this point to say that if you ordered hose from HWH for the front slide, they you will end up with hose way too long. I think this was clever on Newells part because it minimizes the hose expansion variable in upsetting side to side balance of the cylinders. HWH is VERY specific that the front and rear hoses be exactly the same length for this reason. Newell engineered a clever way around it by using the steel tubing.

I do not know if Newell/HWH setup for the front slide continued this way in later years or not. YMMV.

And if there was a silver lining in all the hours spent poking around in typically non accessed places, I found the steel tubing that supplies the front cylinder, accessed through a hatch above the passenger front tire, was unsupported. I have heard a rattle in that area as long as I have had the coach, and I suspect the unsecured tubing was the culprit. Needless to say I secured it before I sealed that hatch back up.