Sprinter van: Bench seat installation in our cargo van

Before we bought our van, we knew if we got a cargo version we'd have to install a bench seat. It wouldn't be as much fun to leave Sefton behind on all of our trips. He's a pretty fun little boy. For whatever reason, this seemed incredibly intimidating to me. Remarkably, two days after we bought our van I met a guy here who parts out T1N Sprinters, and he – just as remarkably – happened to have a 2-person bench seat. He even explained in a fair amount of detail how to do the installation. It didn't seem terribly difficult. Just intimidating.

I poured through forums on sprinter-source.com. I watched a YouTube video a guy posted about removing the fuel tank. That was the crux, after all. The driver's side bracket bolted in above the tank, and the tank was mounted up tight against the van's floor. It'd have to be dropped in order to drill through the floor and secure the bolts.

Oh, and when we bought the van we filled up the tank that weekend. All the way. It's a 26-gallon tank and the 5-cylinder diesel powers the 8500-pound rig at about 25mpg. Eventually, we ended up taking trips with the van just to use up the gas. The last one was to shuttle J up to Squilchuck so he could check out the mountain bike trails. A half-mile after pulling out from the driveway, the fuel light finally lit up!

It's not quite empty and has 581 miles on it. We're thinking we'll get it to 600 on this tank before filling it again. Just not before we drop that bad boy to the ground and get the seat installed.

Step 1: Remove the hose clamps on the fuel intake and vent and then disconnect both hoses

Step 2: Loosen the 13mm nuts holding the two hanging brackets that hold up the tank

Step 3: With J and I securing the tank from below and taking turns loosening the nuts, we eventually removed each nut and carefully dropped the tank to some scrap lumber we had on the ground

The word 'carefully' may not be 100% accurate. Though it wasn't terribly heavy (the tank itself is plastic) with just a gallon or two of gas, there was really no way to carefully set it down. In reality, it fell with J and I providing some resistance. After it settled, I emptied Sefton's sand table and tossed all of his sand on the fuel that had spilled. It wasn't much, but enough to cause some concern when I'd go to drill through the metal above. Diesel or not. 

In the photo above, the key is the framing member that runs the van lengthwise and to which the tank's two mounting brackets are attached. The bolts for the seat bracket would come through the floor inside of that. For mounting it, I read about two options:

1. Drill all the way through, then use a long bolt and attach the washer and nut to it on the outside of the frame
2. Drill only through the floor, then back up through the frame with a hole saw in order to use a shorter bolt that attaches with a washer and nut inside the frame directly to the underside of the floor

I only really ever considered Option 2. A longer bolt has less strength than a shorter one, pure and simple. This is our child sitting in the seat. I wanted it to be as strong as possible. Both required dropping the fuel tank, regardless.

In this photo, the bolt for the short bracket Scott and I installed a few weeks ago can be seen right of center past the emergency brake cable. Bryce included the OEM seat bracket bolts so all I had to do was pick up some Grade 8 washers and nuts. Again, strength here was key and I wasn't taking any chances. I'd read other things will fail before a Grade 8 nut or bolt fails.

Step 4: Drill all the way through the floor and frame with a 1/4" bit (the pilot bit on the hole saw Scott lent me was 1/4" so it'd be easy to guide it back up through the frame)

Step 5: Using a metal hole saw (thanks Scott!), drill back up through the frame. This will provide the space to get the required 17mm socket needed to torque the nut to the underside of the floor

Drilling through the 1/8"-thick frame with the hole saw – up – was surprisingly easy. It tore through the metal sort of like, well, a hot knife through butter. Sorry. It's true.

Step 6: File and paint the bare metal (I'm not taking any chances on rust!)

We were on the home stretch… Now it was just a matter of K in the van popping the bolt through the bracket and holding it tight while I attached and tightened the washer and nut from underneath. In order to hold the washer in place while I reached up with the socket wrench through the hole, I taped it in place (the tape broke free as soon as I pushed the socket onto the bolt).

Oh, while I had been drilling with the saw, K brought us coffees! She's the best.

Step 7: Tighten the nut to the bolt. Then tighten it some more.

Repeat for the other hole. Then install the seat! We earned a short break before having to reinstall the fuel tank. Yay.

Reinstalling the fuel tank wasn't too terrible. To give us more room to get the hole saw where we needed it, we ended up disconnecting the tank's wiring harness. So we snapped that back on. While K and J hoisted the tank back onto the bolts of the mounting brackets, I finessed the vent and intake hoses back in place and clamped them down.

It really helped having three of us. I don't think it'd have been possible with just myself, not even with the help of a floor jack to lift and hold the tank. Maybe, but I'm grateful for the help. J has become quite the mechanic, for bikes as well as vehicles. 

Earlier this year, I had him help me install new front brake pads and rotors on our '01 RAV4. After we finished with the seat, he replaced the serpentine belt on his '04 Matrix. That job ended up requiring him to use our jack and lift up the engine so he could loosen the tension on the pulley. Impressive.

While we worked, Sefton busied himself building his own, umm, something-ma-jig in the garage.

All in all, the job wasn't that bad. Certainly not as intimidating as I made it out to be. Now we can take the boys or a couple of friends. On trips we don't take them, or once we're parked at the spot we'll be camping, we can pull out the seat to make a little more room.

Up next: The body shop…