2018 Raptor 351 Two grey tanks, one valve

[Jayster10]

Hi all,

Hopping someone can shed some light on this. My Raptor has two grey tanks but only appears to have one valve. I have two questions. 1. Have I just missed a valve or does this model have both tanks connected? 2. Do they fill up at the same time or one then the other? Any info would be helpful.

Thank you in advance.

Jay

[Brentw]

Check along frame rails, black handle, hard to see unless you are looking for it. Mine is forward of the axles.

[LHaven]

It strikes me that if you had two gray tanks and they were connected, the manufacturer wouldn't supply two gray tank monitors because the level would always be the same in both.

Sometimes the pull handle goes bye-bye, though on a two-year-old rig this is less likely.

[Harleydodge]

Mine (for the Kitchen grey) is separate from the other two and located in the wheel well aft of the rear tire. Hard to see and hard to find the first time I looked for it.

[chuckster57]

Originally Posted by LHaven

It strikes me that if you had two gray tanks and they were connected, the manufacturer wouldn't supply two gray tank monitors because the level would always be the same in both.

Grand designs had a model (imagine I think) that had 2 separate gray tanks and one valve. The tanks would eventually read the same, but it took a while.

[Jayster10]

Thanks everyone for the help. I will keep looking for the second handle.

Happy 4th of July.

Jay

[Myersjos]

I found my valve for kitchen gray tank behind axles near rear jack

[LewisB]

We have a 2018 353TS which I suspect is very similar to your 351. On ours, there are 2 gray tanks, 2 black tanks, and 2 drain lines. However, note that they drain in an odd (to me) way. The forward drain handles the forward black, forward gray, and rear gray tanks. The rear drain only handles the rear black tank.

Here's why I mention this; we have found that the forward gray tank catches water from the main bath sink & shower plus the kitchen. It fills up rapidly (compared to the other tanks) due to showers and dish washing. You can quickly find yourself with this one tank full and not a great deal in the other tanks. The rear gray tank handles only the sink in the 2nd bath - it gets very little use.

Solution: If you leave the cap on the forward drain line, you can open the dump valves for both the forward and rear gray tanks and "bank" them together. Doing this gives you 41+41=82 gal of gray capacity. The down side: close the valves on both gray tank drains before you pull the cap! In our case, I installed 3 inch "last chance" valves at the end of the drain line where I connect the drain hose. This allows me to "bank" the gray water and still make a connection with the drain hoses before dumping. I always close the gray valves, then dump and flush the black tanks, then use the gray tanks to "flush" the dump hose last.

Just a thought...