Rear Floor Renewal - Add Gray Tank?

[Paul Mayeux]

I was under the rear of the Overlander last weekend and could see up to the plywood deck only to behold a bunch of delaminated plywood. An inspection inside to what could be seen never showed the amount of damage present. So I have now ripped out the first two sections of plywood which gets me to the wheel wells. (I'm just glad I replaced the floor in the front of the coach first - sort of a warm up exercise) Now I have the option of adding some grey water storage. If I elevated the tub enough I could get a thin tank to go between the frame rails. If necessary, I could also reinforce the rails from the axles back although I would probably not tow with the grey tank full. I recall seeing a thread at some time where another owner had fitted a grey tank in this location. Any ideas, comments? I'll post a pic later.

[59toaster]

Levon I think was who fitted the gray water tank. He custom fabricated a tank to fit between the existing frame rails.
I'm concidering doing the same thing as you.
My 59 needs the floor replaced in the rear as well. Mine is old enough that the black water tank is above the floor so less problems with things in the way. My shower is far enough to the side that the drain is out board the main rails. Should be pretty easy on mine. The worst part will be getting the shower drain to a point where it will drain correctly. Might have to put a valve or anti drainback device on that so it cant back flow if I have to move the camper with a full gray water tank. Really I think you need to keep possibly moving in mind. I know several of the campgrounds I plan to go to will not have septic available at the site and I will have to go to the drain station on the way out.
Levon also did something that made good sense and moved the drain towards the wheels to increase departure angle.. I'm going to look and see if I can do the same. My current black water tank dump is also outside the frame rail. What I may do to avoid messing with it at all is just rig up a Y with the stinky slinky. Then have two drain connections under the camper but less modification to the existing black water set up. Dump the black first then dump the gray and wash out the slinky.

I know most people have the tendancy to put the tanks just in front of the bumper but that concerns me with the weight and clearence. I may drop the whole belly pan and try to put the tank closer to the axle. I think it would make drain routing easier with my lay out. Deffinatly make wieght distributing better if I have to drive for any distance with water in the tank. It would also alow a little bigger tank because I could let it hang down a little more without fear of it dragging the ground. Then route it's drain below the frame right behind the wheel and only loose about 2 inches of clearence at the most very close to the axle. That 2 inches would be mute point at that location I would think. Less stress on the frame as well and should not have any strength concerns.

I hope I can find a prefab blow molded tank the right size and avoid fabricating a tank. We will see how that goes.

[Pahaska]

My old Scamp 5th wheel had separate drains for black and gray. The gray was behind the axle and the black in front. I never found it inconvenient. I just had to remember to stop with the rear wheel adjacent to the dump station drain so that the hose would reach from both outlets.

[Paul Mayeux]

As you can tell, I really got into the demo mode. I still have a small piece of floor to replace behind each wheel well. But there are several places a grey water tank could go. I'm going to raise the tub a bit (match the toilet) so that the water can drain into the tank. Also, since I've gone this far, I'm going to replace the rest of the belly pan. I replaced the forward half when I replaced the floor in the front. I used .032 alum and it was pretty tough to work with. Does anyone know where to find some .028. I measured the original pan thickness and it was.028. I found some .025 at Metal Supermarket but that is too thin and it was $120 for a 4x12 sheet which is double what I paid for the .032.