Seafoam is supposed to work well. However, I don't think anything will work good putting it in the fuel tank.

Anyone ever try water torture on a diesel?

Danny

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1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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If you're worried about poor fuel quality the first thing you should do is buy your fuel elsewhere, preferably at a high-traffic truck stop.
Second thing to do is get a better fuel filter. The stock filter is only good to 10 microns, this Baldwin is larger (more capacity) and filters down to 2 microns.
Lower Micron Fuel Filter Mod