Finally joined the forum to give back share some ideas that I put to use on my van conversion. Thanks for all of the great information you all have shared.

2018 15 passenger Express 3500. This is the long wheelbase van.
Some guiding principles for my conversion:
1. be able to carry convert from a family camper back to a 15 passenger van
2. Use the stock interior carpet, trim and panels - for resale in 10 year (or more)
3. Make a comfortable camper for family of 4 to camp in the Pacific Northwest.

Modifications made to date:

• build rear storage benches/ table that double as storage and convert to (almost) queen sized bed.
• Maxxair Fan
• insulation and sound proofing
• LED dimmable Pot lights
• Electrical and fuse box
• Auxiliary battery
• Custom Full-length roof rack
• stowable ladder for getting on roof rack
• trailer hitch

For this post I just finished installing an auxiliary battery for camper functions. Sharing because there does not seem to be much information available for a custom battery mount on these vans. Most people seem to be putting Lithium batteries in the van, which does not work for my build.

I opted for a single 200Ah 8d AGM battery for my install because it seemed to be the most economical (debatable) option for reaching a 200Ah battery reserve. This should allow me to run a small DC heater during cold weather camping. I built a battery mount that attaches to the drivers side frame. installed a battery isolator and an override switch so I can jump the main battery from the house battery. Installed a battery monitor in the dash, battery cutoff, fuse box, 4 extra DC outlets. I had installed the lights and vent fan last year. so this was a modification to hook up to the new house battery and not be paranoid my kids will run the starting battery down.


The test fit for the battery mount. Secured to frame and body. The tray drops down and bolts to the straps for battery maintenance.

View from back side. Mounted on drivers side.

Battery on tray ready to get hoisted into place. This took a lot of finesse, a floor lack, and assistance from the wife. These batteries are about 150 lbs.

Here is the view from the side of the van after installation. I am happy with how low profile it is.

Here is the battery mounted. I welded a plate on the back side to mount the fuse from scrap metal.

Connections under the hood. you can see override switch, fuse, and isolator.

Installed a battery monitor in a open spot on the dash.

For the cut-off and fuse box, I mounted them behind the passenger-side panel. I cutout a section of the panel and can attach it with Velcro for a cleaner look. You can see one of the extra outlets in the picture. There is one more on the passenger side, and 2 on the driver side.

Still have a bit of clean-up to do on the wiring, but works well, and hard parts done.

 

Thanks for this JMANWEST, I have the same exact van (2018 3500 15 Pax van), Im leaving today to go pick it up from Quigley (did a 4x4 conversion plus 2" lift). I haven't changed anything on the inside, do you have plans/photos of the benches/bed that you built? I am looking to either build rear wheel well storage boxes or something similar to what youre doing. I am in the same boat in that I want to be able to flip back to pax van as my kids are still all in the house. Happy Converting!

 

Super jealous of your Quigley conversion. So cool.

For benches, I built open back and bottom for air circulation. To secure I used an adjustable eye-bolt that attaches using the rearmost stock seat anchor pins. 2 on the driver's side, I needed more stability because that is where I attached my Lagun adjustable table mount. (The Lagun mount is pricey, but is fully adjustable and attaches to bottom of table when I make the bed.) There is a lip on the benches that I use to slide 4' table onto for bed, with a few scrap board for last. Few feet. The bed is stable for sleeping and driving.

Drivers side bench has a cut-out so the factory rear heat/air still works well. (Also great place to store camp axe or collapsible shovel).


Benches installed in table mode. Table arm adjusts. When driving I put it to the side like this for easy access through back. Swings to center when we want to use table.

Benches have spring loaded hinges so they stay up and down.

Seat anchor pin slides into this eye bolt.

Bench installed with door open showing attached to seat anchor. This design also let me use the stock jack mount.

View from the top.

Table slides on lip between benches.

 

Thats great, thank you for those pics!