What's the absolute maximum range of your Duster?

Back to your original question. The OEM tank is listed as having a 18 gallon capacity. If your tank is 16 gallon it is the wrong one but as long as it fits it really isn't a issue. Just a shorter driving range.
Mike, my original owners manual shows a 16 gallon tank. This photo is from page 52 of the manual showing the fuel capacity. In any case, it's a pretty small tank.

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