The new 2007 Escape trailers have 14 gallon black and 20 gallon gray water tanks. The older models like mine have 7.5 gallon black and 14 gallon gray water tanks. As we like to dry camp, I wanted to increase the waste water storage capacity to my 2006 Escape.

I installed a custom made auxiliary tank system that added approximately 13 gallons of extra waste water storage capacity (though I only plan using 11 gallons of capacity to keep the vent line clean) and a new capability to drain the gray water tank through a garden hose. Although I can transfer both gray and black water into the auxiliary tank, I will primarily use it for black water storage and use the new garden hose drain to keep the gray water tank level below full. Of course the new gray water drain will only be used where allowed.

I installed the auxiliary tank forward of the axle. Below are before and after pictures of this area:

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Here is the sketch used by George’s Custom Plastics Inc http://www.geocustomplastic.com/index.htm to make the tank and a picture of the tank before installation. George did a great job on the tank; it is 3/8 inch thick and darn near armor plated. It cost $250 including shipping. The stressful part of the planning was lining up the vent and drain holes to mate with the respective plumbing. In the end that part turned out near perfect. If I did it again I would make the tank and inch or two shorter to allow more slop in the installation of the plumbing.

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The tank is supported by the brackets shown below.

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Do to space issues, I'll continue on the next post.

The tank is supported by the brackets shown above and ¼ inch continuous threaded rods and aluminum and steel L angles as shown below. The green hose is a Quickie Flush system for clean out.

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To provide clearance to the existing trailer frames and the four bolts that attach the frame to the cabin, I glued two pieces of 11/32 inch plywood together, drilled holes so the plywood would clear the existing bolts, trimmed the existing bolts to be flush with the plywood and glued the plywood to the bottom of the trailer. The plywood is shown below.

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Here is a sketch of the final installation details.

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The vent system took the most planning. On the picture below, you can barely see the white 1 inch diameter PVC pipe coming out of the threaded fitting above the black 3 inch ABS drain line. The PVC pipe is attached to a 90 degree elbow and goes up through the bottom of the trailer.

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The vent line comes into the trailer in the kitchen cabinet floor, just aft of the shower. It goes up the forward wall of the cabinet and into the wall between the cabinet and shower. The Tee fitting in the middle of the vertical leg is for a garden hose so I can flush the vent line. I expect that the vent will get fouled as it mounted on the side of the auxiliary tank, the clean out will keep it clear.

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Inside the shower, the vent line comes through the wall and into a saddle fitting on the existing 1 ½ inch black water vent as shown below.

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I made the saddle fitting from a normal 1 x ½ x 1 slip fit Tee fitting. I cut the fitting in half as shown below and then sanded the raised boss around the ½ inch hole so the fitting fit snugly on the existing black water vent line.

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I used a long ¼ inch drill bit to drill a pilot hole through both sides of the black tank vent, the shower wall and into the adjacent kitchen cabinet. I then used a piloted hole saw to drill from the opposite direction; from the kitchen through the wall and one side of the black water vent. I then installed a ¼ plug in the remaining hole in the black water tank vent. The picture below shows the long drill bit in use.

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The water manifold allows me to drain the gray or black water tank into the auxiliary tank, to drain the gray water tank via a garden hose, and dump each tank individually. I cut the existing gray water drain line a couple inches before the existing 1 ½ inch gate valve and rotated the existing 3 inch black water fitting and attached 1 ½ inch gate valve 90 degrees so it faced aft. The picture below shows the manifold before the modification.

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This picture shows the manifold after the modification. The green garden hose is for the Quickie Flush.

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I added a Tee fitting to both the 1 ½ and 3 inch fittings. On the 1 ½ inch gate valve I added this assembly to link up the gray water tank and provide the garden hose spigot for draining.

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On the 3 inch line I added a double clean out Tee fitting with a 3 inch gate valve on both ends of the Tee. One gate valve empties into the auxiliary tank, the other has a bayonet fitting for the flexible sewer drain line.

This picture and a couple more to follow give various views of the water manifold.

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When camping I can use the gray and black water tanks as originally designed; this gives me 7.5 gallons of black water capacity. If I close all valves except the original black water tank valve then 1 ½ to 2 gallons will flow into the manifold, this gives me about 9 gallons of black water capacity. If I open the 3 inch valve for the auxiliary tank I have approximately 20 gallons of black water capacity. So far it has worked well, last weekend we had to use the 9 gallon capacity.

Next week I expect to use the auxiliary tank for both gray and black water. When doing this I will need to plan when to transfer the water. I am going to wait until the gray water tank is half full, then transfer gray water into the auxiliary tank. This should be about 4 to 5 gallons of water. Then I’ll transfer the black water tank when the black water tank is full to add another 7 ½ gallons. I’ll transfer the gray water first so I don’t contaminate that tank with black water.

The tank was a bit hard to install, I didn’t enjoy drilling holes in my beloved Escape but I learned a few things that I can pass along later if anyone is interested in doing it themselves.

Great Report Thane. I am blown away with your detail. My problem is when I am building something, I don’t take time to shoot photos.

I am wondering a couple of things.

1) It looks like you have lost a lot of ground clearance. Is that right?

2) How long did it take to get the tank made?

3) Is this the company?

Georges Custom Plastic
3250 B Street Northwest Ste C
Auburn, WA 98001-1725
Phone: (253) 939-1575
Business Types: Plastic Products Manufacturers

Thanks for the response.

I only lost an inch or two of minimum clearance as the original waste lines hung to about the same level, though I did increase the overall vulnerable area as the tank is a bigger target for road hazards than the original plumbing. Overall the 2 inches or so of lost clearance is OK as the tank is near the axle, the 3/8 inch thick tank with the L angle supports is pretty stout, and I had the raised axle option installed when I bought the trailer.

The tank was made very quickly, I received it about 2 weeks after ordering it from George's Custom Plastics (yep, the same George's as your e-mail). They did a great job and helped rush the order so I could get it installed in time to go beach camping. I recommend George's for anyone who needs a tank made, it was a beautiful thing.