by Garrett McKinnon
VehicleMD Staff Writer
Originally published in Spring 2011 Issue

I've never seen the tiny bits of cholesterol floating around in my bloodstream, but my doctor tells me there are more of those bits than he would like. So, I exercise, try to eat right and even gulp dietary supplements like flaxseed and cod liver oil in a mostly successful attempt to keep my cholesterol under control.

But did you know that your car's engine can have its own "cholesterol" problem? I'm not alking about the dissolved fats and sugars that course through our bodies, but rather the gooey tarlike deposits inside your engine called sludge. Like cholesterol, these gel-like deposits—formed when the motor oil is over-stressed or contaminated—can bond together in your engine's oil system, forming ever-larger clumps that may over time clog critical oil passages, blocking oil circulation to parts of your engine. This can lead to excess wear, component damage or, like the heart attack we all try to avoid, a sudden catastrophic engine failure.

Drivers of pre-owned cars should be especially cognizant of this problem. Unlike your body, you can't be certain of how your car's previous owners treated the vehicle, and even if you have your car's motor oil changed frequently, the damage may already have been done.

Plus, according to the technicians and mechanics who work on vehicles every day, certain types of cars and/or engines are prone to sludge build-up.

"There are some engines that are just prone to building a lot of oil deposits," said Jim Davis, technical servic emanager for Sea Foam Sales. "It's in their design. There are certain engines that will cook the oil on the inside of the engine. This leaves a lot of oil residue that can actually just keep building and building."

Fortunately, there are things you can do for your car's engine, even if you can't see inside to measure whether it has any sludge accumulation.

Certain formualtions of chemical additives and cleaners exist that can actually dissolve and re-liquify most kinds of oil sludge buildup. These additives can ehlp turn varnish, gum, oil deposits—really almost any type of gunk that might be in your engine—back into a liquid state. This liquefied sludge will then be circulated through your engine's oil system, where the oil filter can do its job and screen out the harmful deposits, leaving your engine in a much cleaner state. (Makes you wish they had a "cholesterol filter", doesn't it?)

"If you put an additive in your oil that will help get rid of oil buildup, as well as prevent it altogether, you're going to have a lot less wear and tear on the parts," Davis said. "When you get an engine that is gummed upd, oil can't get to everything it needs and you can have a lot of premature oil failures due to excess oil buildup. Any time you can keep an engine clean, it can make your car last longer and run more efficiently."

Running a so-called oil system cleaner or motor treatment through your car's engine every so often can go a long way toward helping keep it clean and free of sludge, so ask your auto service technician whether such a product might be right for you. Because even your car could do with a lower "cholesterol" level!