[Evans, Marv]

I'd listen to Mike (Lubemaster) and Sammy. There are quart sized additives you can buy to add and run your engine only about a few minutes to clean the engine out. That sounds nice but I don't totally trust their claims. I would be afraid of chunks of gunk clogging up my filter with a quick treatment like that, if you truly have a significant amount of sludge in there. That would seem especially true with any treatment if you have a full flow filter on the engine, which is usually the case. If that kind of filter gets clogged from a large amount of sludge, just think of what can happen. I've seen filter canisters break from the pressure, not to mention what can happen inside the engine.