well, im doing an oil change this weekend, what is the vote from the techs... marvel or seafoam?

autoRX says it not solvent based....

 

Your engine isn't that old, go with the seafoam for now.

 

http://www.schleeter.com/oil-sludge.htmAWESOME Article should be made a sticky

 

Thanks for the quick response. I almost traded it in for a new A3 a couple months ago -- damn! I've read so many bad stories on the web that I was assuming they wouldn't cover it without receipts/proof for every oil change.

So I take it the OIL indicator can mean low pressure??? The manual says "add oil" so I assumed it was an oil level sensor issue especially when the used oil looked so clean. The manual said to shut the engine off for a *different* oil indicator, so I assumed that one was for low pressure.

 

Well you need to look at the pictures and see which oil light you have. The oil pressure light will generally flash and beep at you when it happens.

 

I'm on a trip right now and the manual is at home in the glove box. The one I got was the oil can with "OIL" under it -- the manual says that means you should check and add oil, but my oil level was fine.
The manual describes two other oil indicators (that have never illuminated in my car). One said "sensor". I don't recall what the other looked like, but it was a blatant "shut the engine off" thing.

 

It's 25-35% naptha, according to their MSDS. Naptha is a petro-based solvent, available in bulk at any hardware store to clean brushes and spills associated with oil based paint. It's also a primary component in most fuel injector and throttle body cleaners...and...auto parts cleaner, commonly known as solvent! Soak a grease packed bearning in some naptha for a while, you'll get it sparkly clean with a little extra effort because it broke down all the grease. Grease is just thick, waxy oil. If naptha can break down grease imagine what it does to relatively thin motor oil.

I never saw the thread that lead to this, but I gather that someone got a flashing oil light in the middle of nowhere, pulled over and didn't see a lack of oil, then drove on to ruin their engine in 100 miles. A bit of Sea Foam would have saved the motor, is that the gist of it?

In that case sure, it's better than spinning a bearing, but I would expect a some excess wear from driving it 100 miles with it in the oil system. But as routine maintenance the cure may be worse than the disease. I'd use it in an old powerboat if I had one, but engines like ours didn't exist in the 1930's when Sea Foam was developed.

BTW, my girl's 2000 A4 2.8L just hit 60K and had a fair amount of sludge in it. I cut that in half just by driving it 3000 miles in 4 days. Problem caused by too many short trips/thermal cycles. There might be a lesson there for y'all with 1.8T's, maybe you just aren't driving them long enough to get the oil good and hot for extended periods.

In any case, it doesn't speak well for Audi's design process and development at the time, but at least they caught on eventually, and back it up beyond the warranty period.

 

My bad, I thought "autoRX" was someone's username, not a product, and they were referring to Sea Foam.

Sorry 'bout that. Looks like Auto-Rx is a very different product but according to their MSDS, it's still a "metal cleaning compound." My comments above were about Sea Foam's naptha content and have nothing to do with Auto-Rx, which doesn't contain any naptha. I'm not a chemist but Auto-Rx sounds like a safer product, but should still be used with care, and a healthy dose of skepticism.

One thing to keep in mind is that if any of these little companies invented something that the big petroleum corporations could use to their advantage, they would pay big bucks to the little guys to license their invention, buy the company out and own the rights exclusively, or make something similar and put it in their products.

Or as an old buddy who was a petroleum engineer for a major (and well regarded) petro company once told me about fuel and oil additives: "If it's good for your car, we're already using it."

BTW, I've always used Mobil1 and top quality oil filters (not Fram) and have never had a trace of sludge or any lubrication issues in any car I bought new off the lot.
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im sure short trips have a lot to do with it..... fortunately, i drive 30 miles each way to work... my dad has a 97 or 98 a6 1.8t in greece for his beater over there and he has 250,000 miles and not a problem one... just regular wear and tear...

 

Short trips has a major affect on sludge, you'll notice that when people only drive short distances you will have evidence on the bottom of the oil cap. The engine has to be HOT when cycling oil through it, oil doesn't like being cold.