Another DIY Camper Conversion 158" 2002

Bought a used 2002 158" a few weeks ago. It had an expeditor package installed from stoops freightliner in ohio. It has an inverter, second battery, and roof vent already installed. I've been to Doktor A for a checkup and its surprisingly free of rust. Looks like it was repainted at some point but it is a sprinter so of course its got some rust spots. I've been reading lots of stuff on here and found tons of good info so far.

I'm not going to make this a true RV, no shower, no bathroom, no water system, no rear ac. Just want to get it set up with a bed, storage, stove, heater, some windows, fridge, and insulate it, maybe add a makeshift sink, and then add as i need over time.

Things i have done so far

-new windshield from a high quality glass shop
-new cabin/ air filters
-Changed rear diff oil
-new rotors and pads all around
-parking brake adjustment and grease
-new 150a alt (cant believe this was not upgraded from the dealer who put the house power in)
-new belt
-replace climate control lights
-exhaust repair to pass inspection
-took apart sliding door lock mechanism and regreased it so it works and closes easily
-wired in a different stereo head unit that actually works


Old inside...

I started the conversion by taking out the partition/bulkhead, cabinets, bed, and stripping out the electrical outlets and fiberglass insulation from the walls and ceiling. I also took apart the doors, headliner, and removed the seats to fix some rust spots under the seats caused by a leaky windshield. I decided on prodex foil faced foam insulation for the base layer of insulation against the metal. I am adhering it using v&s 1081 spray adhesive. So far i have only used it on the pass side of the cab and the sides of the high top.

These photos are from yesterday, today i took out the drivers seat, sanded, used naval jelly on the rust, and primed it using a self etching primer. Will hopefully insulate and button up the cab and reinstall the seats tomorrow.

has anyone ever used a bug bomb inside their van? There are lots of stink bugs in this van. I've already removed a ton with a vacuum but i assume theres a bunch hiding out inside the dash and i'd like to wipe em out before i start building stuff inside.

How much of a pita is it to remove the floor? I wanted to put prodex under there but i'm not sure its worth it to drill out all the rivits.


A Dad owner with a '03
How much of a pita is it to remove the floor?
It's not too bad to remove. I regret not putting more insulation under mine when I had it off. The floor gets very cold in winter camping.

what have people used to insulate inside the ribs? i was thinking great stuff foam for windows and doors but i would need to drill some holes in the ribs to reach down the sides.


New member
I used about two cases of Great Stuff to fill all of the cargo area wall space including the doors. I used some Great Stuff foam to "glue" rough cut isocyanurate rigid foam panels into the ceiling cavities. I did not bother to insulate the front doors or to drill holes to reach hidden space.

I did separate runs of smurf tubes for the ac, dc, stere beforehand. I did not smurf a wire to the license plate light and had to dig through the foam to repair that wire. No problem to refill or touch up small spaces.

The insulation works well enough that the Espar Airtronic d2 had no problem when we camped near 0 degrees F.

I could have added foam window blocks or curtained off the front but we do not camp enough that cold to bother for the energy savings. I do have some fancy mylar thermal quilt fabric and it is on the eventual project list for night use.

I kept the original floor and routed L track into it. I am too tall at 6'4" to add any substantial insulation over the floor on my 02 158" 2500.

If it mattered to me I would insulate the underside cavities. Probably use Coroplex (sp?), the usual rv plastic to seal the insulated areas.

My back up plan was to install a temporary "winter" floor. I'd leave a center aisle for my height and put an inch or two of rigid foam covered with thin ply on the rest of the floor where cargo is usually stored anyway.

I figure my substantial but limited insulation has cut the heat load by at least 50%. The furnace made it unnecessary to do more. It would be different if I wanted to air condition the rear while drycamping. That would justify much more insulation since electric btus are so much harder to get than diesel ones.

My floor has only been improved by commercial 3x5 welcome mats. I get the van very dirty with all my boating and it is good to be able to shake those out. Otherwise I prefer a smooth floor for cargo with everything secured. I want to be able to slide anything heavy when I want to.

Good luck.

slow going in the cold. i should be inside my friends heated garage next week, hopefully finish installing the prodex on the walls and floor. Ceiling and cab are pretty much finished.

I also picked up some enguard polyester insulation on my way back to pittsburgh in harrisburg at middletown lumber.

Cab insulated under the mat with prodex

i've also encountered some strange light behavior. Once i start the van all the marker lights come on and stay on. The switch is off but the side marker lights, 6 lights on the side of the van, license plate lights, tail lights, and instrument cluster are always on when the van is running. when you turn the light switch on the steering column the only thing that comes on are the climate control lights and gear shift indicator lights. Its been like this since i got it but i didnt really realize everything was on all the time. I mentioned it to andy but he didn't seem to know what was causing it. any ideas?


New member
Is it a Canadian van ? Day lights are mandatory here and often manufacturers just put all parking and marker lights on at the same time when you turn on the ignition. My Sprinter is a 2007 and I never play with the light switch, always OFF except if I want to turn on lights when the ignition is OFF.
finished up all the prodex base layer a while back and put the floors back in. Been having a big problem with enguard. got 2 batches that were both messed up. spoke to tim and he said he would send me out 2 bundles and that was 12 days ago. email from this week has gone unanswered. Its really holding up my entire build. I plan to put the enguard in the walls then another layer of prodex as a vapor barrier before i put up the wall pannels.

Ran some wires, but i'm going to keep my electric pretty basic. Resealed the vent, and top seams with sikaflex, and also resealed the rain gutters on both sides. Been hitting some rust spots with sem (rust sealer), and also took care of rust in the foot wells of both doors.

Put the headliner back in and wired up some speakers in there

bought this window online for $15 to go right behind the drivers seat its about 20x30 and 2" thick. no trim ring so i have to make one to secure it.

was thinking about getting 2 of these for the rear where i plan to put the loft/bed.

do i need to use butyl tape to seal the windows against the body or should i use sikaflex?


A Dad owner with a '03
do i need to use butyl tape to seal the windows against the body or should i use sikaflex?
I like the adhesive that autozone sells to install a glass windshield. It comes in a coil (sold in a box) I think its a urethane. I used it to install all the windows and seal every other hole I cut throught the skin on my van.

has anyone insulated the upper section of the rear doors? i was thinking about cutting an access hole and sticking some insulation inside. Wonder if this would weaken the doors?



on my 158 2003 i've put 2 inch styrofoam on the roof and a lot of mineral wool on the back walls. Also with the insulation you use i've made a curtain to separate the sleeping area from the driver side, too much heat loss due to front windows.
In fact I've put so much insulation to arrive at the same level with the van transversal inforcements( sorry I don't know their real name, ), the metal structure.
But if I had to do it again i'll put styrofoam everywhere, maybe 3 inch for the walls and spray some foam into cavities etc.2-3 inch styrofoam we use in homes so is very effective, but there is only one construction adhesive sold in tube which work with it

have safe travels


i drilled a 2 holes and cut a small 4" square flap in the upper section of the door. doesn't seem like they noticed one bit. I put some enguard in there and now when i slam them they make a nice fat thud. no more t1n can noise.

bottom half insulated with enguard and putting up a second layer of prodex over it as a vapor barrier.

I did a bunch of other stuff (floors in, more insulation in, some wires run, boxes made to close in wheel wells...)and will post pics in a bit. Time to kick it into high gear. Planning to start my trip mid/ end of may but i'm not getting too fancy with the electrical/ water / etc.
went out today to check on my new injector from Dr A and tighten down the plastic cover and realized the front of the battery was dipping down in the engine compartment.

the culprit

the donor

the result (with some help from a die grinder + some cursing/ throwing a few tools) fits my battery perfectly but is a about 1 1/2" less in the width department from the oem tray (dealer wanted $170!) The 4th bolt (front fender side) was completely rusted into place and i couldnt get it to move at all. So i put some SEM rust sealer on it, primed it and it now acts as a support for the battery tray. I jumped on the tray and couldn't get it to move so i think the bolt will provide adequate support.

Inside. Prodex against van, enguard in the space, prodex vapor barrier

after realizing my widows would not work on the sides due to the curve of the walls i relocated them to the rear doors. Some of the urethane rope squeezed out a little on the corners when i was trying to get my inside window panels to work correctly. I like them and they were about $200 shipped for both. close to 20" square.

Inside panels. shhhh. don't tell me the left corner on the pass side door is higher than the rest of them. It was a long, hot day with lots of unsuccessful attempts. This is as good as its getting for now. Putting up cowl board grey sheets on the roof. so far the first 2 didn't come out as good as i hoped.

i'm also realizing my woodworking skills are much worse then i was hoping. Here's to measuring 3 times and still having things out of square!
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