Friday, June 26, 2009

The right oil for the right job.

Time for a quick refresher: in multigrade oils, there are two viscosity ratings. For example 5W40 indicates an oil which is thinner when cold and thicker when hot. The "W" indicates "winter" - more typically "cold". So 5W is an oil which has a viscosity value of 5 when cold. The other number is the viscosity when hot. In this example, a viscosity value of 40. So why use a multigrade oil? Well when the engine is cold, you want the oil to flow as quickly as possible to all the engine parts, and also not to impede the power of the starter motor in turning the engine over. But if the engine oil stays thin when it gets hot, then it does no good because it runs too quickly, and doesn't stick to any moving parts. Hence multigrade oil that thickens up with temperature.
So which oil should you use? Suffice to say that a 5W oil isn't going to give you much benefit if you live in Singapore in the same way that a 20W oil won't do you any good if you live in northern Alaska. Here's your rough guide:

5W-30 Cooler climates, like Sweden or Canada
10W-40 Temperate climates, like England, northern Europe, New Zealand
15W-50 Hot climates, like Italy, Spain, Egypt, Australia

Monday, June 22, 2009

The 2009 Mercedes C Class

Another business trip, another car rental. This time the glitch in my corporate account means that I'm paying for a Ford Focus but driving a 2009 Mercedes C Class with only 15 miles on the clock.
Initial impressions? Very nice. It drives pretty well for such a large car. It's an automatic, which means it has a "C" and "S" mode, "S" mode simply meaning - "the mode with most of the electronic shackles removed". It took me a while to find the 12v accessory socket though. I found one in the glovebox, but the small cubby hole at the front of the dash is so well disguised I didn't find it until this morning.
One thing that's a little bizarre is Mercedes choice of stalk controls behind the steering wheel - there's only one. It does headlights, washer/wiper and indicators all on one stalk. My daily driver is Japanese so I'm used to controls split across two stalks, so driving the Mercedes from the airport yesterday, I spent a lot of time flashing the cars in front and randomly indicating left whilst trying to use the windscreen wipers. The location of this giant multi-control stalk is also a bit Ford-like in that it's very low down. If the car was a manual, I'd no doubt have snapped it off by now because it just about touches my left knee even with the adjustable steering column in the highest position.
Otherwise it seems Mercedes have come out of their early 2000's funk when they were building just awful cars, and it looks like they're trying to regain their status as a luxury marque. It's quiet and comfortable, and there's definitely something unique about driving with a visible emblem in front of you - in this case the Mercedes star that protrudes from the front of the hood.
Would I buy a C-Class Mercedes (or any Merc for that matter)? Still probably not. Not only because of the cost, but it's just too much luxury and too many nanny items for me. It doesn't feel like driving a car any more - as the driver I feel too far removed from the process in it.