Installing Auxiliary Fuel Taps on S&B Sprinter Tanks

When building on a Mercedes Sprinter platform, the stock fuel sending unit includes one auxiliary fuel line that can be tapped to supply diesel to accessories such as heaters or generators. If your setup requires two diesel-powered devices, installers sometimes add an aftermarket Auxiliary Fill Cap like the one shown below.

While it is technically possible to install an Auxiliary Fill Cap on an S&B replacement tank, we recommend instead T-ing off the factory auxiliary fuel tap when powering multiple heaters or devices. This approach avoids drilling into the tank, which can introduce leak risks and void warranty coverage.

⚠️ Installation Advisory:
If you choose to use an aftermarket fill tap, ensure it is installed high enough on the tank to prevent leaks when the tank is full or during fuel slosh. Always verify that the tank still fits correctly after installation.

Note: S&B Filters is not responsible for leaks or damage resulting from modifications involving aftermarket auxiliary fill caps.

Sprinter Auxiliary Fill Cap

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