How much do you value the engine in your car? Think about it, because the life of your engine depends in no small part on the quality of the oil you put in it. Oil is the lifeblood of your car’s engine. From the mid 80’s for 8 or 9 years there was a veritable revolution in car engine oil. All oils are no longer the same. Thanks to the increased popularity of sporty GTi’s, 16 valve engines and turbos in those years, in combination with the devastating problems of black death, the days of one oil catering for everyone were over.
Take Castrol for example. They led the field for years with GTX. This was surpassed a few years back by semi-synthetic and fully synthetic oils, including GTX2 and GTX3 Lightec. Now, that’s been surpassed by Formula SLX which will cost upwards of £50 ($75) for 5 litres. And most recently, Castrol GTX Magnatec which is muscling in on the hitherto separate world of friction reducers (and we’ll deal with them later, on the additives page.).
What does my oil actually do?
An engine oil’s job is primarily to stop all the metal surfaces in your engine from grinding together and tearing themselves apart from friction, and dissipating the heat generated from this process. It also transfers heat away from the combustion cycle and must be able to hold in suspension the nasty by-products of fuel combustion, such as silica (silicon oxide) and acids. It cleans the engine of such chemicals and buildups, and keeps the moving parts coated in oil. Doing this helps minimise exposure to oxygen and thus oxidation at higher temperatures. It does all of these things under tremendous heat and pressure and for the most part without succumbing to fatigue or black death, the ultimate engine destroyer.
What the heck was Black Death?
Black death first appeared in the early 80’s when a horrible sticky black substance was found to be the cause of many engine seizures in Europe. Many engines were affected but Ford and Vauxhall (GM) suffered the most. Faster roads, higher under-hood temperatures, tighter engineering tolerances and overworked engine oils turned out to be contributors to the problem. The oils just couldn’t handle it and changed their chemical makeup under pressure into a sort of tar-like glue. This blocked all the oil channels in the engines, starved them of lubrication and caused them to seize. This could all happen in a matter of minutes. I don’t recommend this but you can reproduce the effect with a frying pan, cooking oil and a blowtorch. The cooking oil will heat up far quicker than it’s designed to and will turn to a sticky black tar in your pan. Either that or it will set fire to your kitchen, which is why I said “don’t do this”.
Anyway, burning kitchens aside, Black Death was the catalyst for the production of newer higher quality oils, many of them man-made rather than mineral-based. Black death for the 21st century
There’s a snappy new moniker for black death now, and it’s called sludge. The cause is the same as black death and it seems to be regardless of maintenance or mileage. The chemical compounds in engine oils break down over time due to prolonged exposure to high temperatures and poor maintenance habits. When the oil oxidises, the additives separate from the
VW / Audi sludge problems
While the the 1.8T engines in Audi A4’s, Audi TT, VW Passat, Jetta, Golf, New Bettle, are all very prone to sludge build-up, Audi/VW does not have an extended warranty for them from the factory. The factory warranty is 4 year/50,000 miles but it can be extended if purchased. Although Audi/VW now has 10,000 mile service intervals, oil changes can be done between “services”, and should be done if the vehicle is driven in heavy traffic, offroad, and non-highway use. Also, Audi/ VW will only warrant an engine if the customer has proof of all their oil changes. As of 2004 I belive all 1.8T engines must use synthetic oil.
So if you own one of these sludge-prone engines, what can you do? Obviously, Volkswagen Audi Group (VAG) recommends that you use only VW/AUDI recommended oil which at the time of writing is Castrol Syntec 5W-40. You should also keep up on your oil changes, making them more frequent.
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