Any product that can reduce the amount of soot produced by a diesel with a catalytic converter will increase performance/fuel economy because the cat won't plug up as much.

I don't buy the claims it actually cleans the cat(directly) but it may reduce soot emissions which will improve the flow through the cat which will reduce other emissions because the engine doesn't have to work as hard. It may not be snake oil and even if it is, an OM617 will run on snake oil.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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