Roof rails are a handy addition to any Sprinter but not all vans were ordered with the rails factory installed. Below is a How-To article on installing the factory roof rails so you can mount any number of items to your roof.
Our rails will ultimately be used to attach a roof rack to the van and support solar, an awning etc.
The van comes from the factory with holes already punched into the body to accommodate the roof rails, even if it doesn’t have the roof rails installed from the factory. There are plastic plugs in the holes with adhesive sealing them from the weather. These plugs will need to be removed to install the rails.
Items required: OEM Roof Rails
Note On Roof Rails: I chose to go with the OEM roof rails…if you shop around you can find these for not a lot more than the aftermarket units and you know they will fit and work perfectly. Prices vary WILDLY on the oem rails depending on where you order them from. The link provided above was by far the best price on OEM rails that I could find and competitive with aftermarket rails.
First up and the most time consuming part of this job is removing the headliner to gain access to the factory holes/plugs. If you have a cargo model its simple and you just go right to work, a passenger van like ours will need the entire headliner removed to install the rails. This process is time consuming but not overly difficult. Search YouTube for “Sprinter Headliner Removal” for some great how-to vids on this process.
With the headliner removed its time to install the rails.
Here’s a photo of one of the factory plastic plugs that seal the rail mounting holes, viewed from the roof…
And the same plug viewed from inside the van..
Removing the plugs is pretty easy. Use a heat gun from inside the van and heat the plastic plug to the point where it just starts to melt/deform. At that point shut off the heat gun and use a screw driver to push up on the plug from the inside, the plastic plug will pop right out! While the adhesive is still hot use a plastic scraper to remove as much as the adhesive as possible on the roof.
Piece of plastic lexan cut to use as a scraper, a cheap plastic scraper from the local hardware department would work here as well 👍
Up top after cleaning it up with the scraper.
Working your way down the channel removing all of the plastic plugs.
Here I’m using a little acetone to clean up the remaining adhesive around the holes. Note: Acetone is nasty stuff, wear appropriate gloves to keep it off your skin and make sure you have a lot of good ventilation.
Before cleaning with acetone…
Here’s one of the studs on the roof rail that holds the rail down to the van. The rail has a rubber washer at the base of the mounting studs to seal the rail against the roof and keep water out.
I added some Butyl rubber around the base of the stud to ensure a water proof connection to the van. I’ve read stories of the factory installed units leaking and I don’t trust the rubber gaskets alone. Better safe than sorry 👍
With the rail now installed on the Van I placed a small amount of Butyl around the base of the stud on the inside of the van as well, just another extra measure as I don’t want to remove the headliner again down the road to fix a leak!
I applied Loctite 243 to the threads (another extra step to make sure the nuts don’t come loose) then started slowly tightening the nuts down. I slowly went back and forth on the nuts to allow the Butyl to ease out between the tightening steps. Eventually they were all tight and the rails are now in place.
Now re-install your headliner if you had to remove one and your done. 👍