I guess you don't watch Mythbusters do you...

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I tried not to quote Mythbusters, they miss the point sometimes. But I guess that one was about right. <img src="/forums/images/graemlins/cheers.gif" alt="" />

I didn't see it, can someone fill me in?

mog uses 40w and it's a 62. some things just don't change.

What's changed (to me) is the "0" part. 40W has long been used by MB. 15W-40 has been the oil of choice for many of their engines. 0W-40? It's a first for anything I've owned. Snowmobile oil. <img src="/forums/images/graemlins/wink.gif" alt="" />

I need to find out if 0W-40 can be substituted in engines that have been running 15W-40.

Frank

Frank I can understand the new oil viscosity spec.'s. However i agree that 13000 and 15000 oil changes just does not make sense. I understand that the modern oils do not break down or wear out as easily but my question is what happens to the condensation, engine acids, unburnt gasoline and normal engine wear that is mixing with the oil during this long oil change interval?

Conner -

Same here - I used to think I understood the oil ratings until I read the MB recommended list - 0W-40 from one manufaturer, 5W-30 from another, etc. - all 229.5 rated.

I don't find fault with 40W - it's the 0W part I question in 100 degree weather. Obviously in higher temperature the oil won't thin to 0W, but with older (dino) oils, there was often a low/high temperature grade number increase in warm weather as opposed to cold (such as 10W-30 in winter, 15W-40 in summer).... maybe it's just a (more expensive but) proven oil over a wider operating temperature range.

I've long felt that the fact that synthetic oil doesn't break down as quickly (justification for long service intervals) overlooks the accumulation of deposits in the oil. Granted, many (maybe most) of the deposits come from non-synthetic oil itself as it breaks down, but I'd have to think that many also accumulate from engine wear and combustion residue. The alternative is to perform the oil analysis tests, but by the time you add that cost to the cost of synthetic oil, it seems to me that the savings is negated and the hassle level increased. It seems better to me to use a reasonable quality dino and change it often, but I'd really like to see a real-world study over time.

I'll certainly use the recommended oil in a new car, but I'm questioning whether the use of synthetics is justifiable in the Gen1 MMC engines.

Frank

The A/C may create more HP loss directly at the engine, but driving with the windows down IS just like dragging a parachute. If you haven't tried it, drive across country with all your windows open and the quarter windows folded out, then repeat the trip with your windows shut and the A/C on. Open windows create more drag lessening fuel economy.



AHEM! When I originally purchased my Raider, it got 18mpg and gas only cost $1.00-$1.20/gal! Modding it is my fault, and I suffer ~1.5mpg because of it, but I literally pay twice as much to fill up the tank now as I did 4.5yrs ago. At the time I could afford to buy it, I could also afford to fuel it. Not so much anymore. <img src="/forums/images/graemlins/frown.gif" alt="" />

Oil is really interesting. If you want to find out all about it go to www.bobisthoilguy.com. It is a forum of oil FREAKS! <img src="/forums/images/graemlins/zombie.gif" alt="" /> (I mean that in a good way).

Synthetic vs Dino is the age old question and there is no final consensus. I personally am sold on Synthetic. Dino cannot match Synthetics flowability at cold startup.

As far as fuel dilution, condensation and the other crap in the oil. As long as you drive some longer trips all of that will evaporate. Engine Acids? - the synthetics have a higher ability to nuetralize acids than most dino oils. Engine wear particles? - they are suspended by the additives in the oil.

If I had that MB I would of course only use the MB recommended synthetic, and I would change the oil and filter when the oil life indicator reaches 25%.

My Passat had a recommendation of fresh oil at 5000 miles using non synthetic. Over time it was discovered that the engines fail. Now the recommendation is for synthetic to avoid sludging failures. The oil life varies vehicle to vehicle depending on the amount of oil in the sump , its operating temperature and how well the rings seal.

Kevin