Originally Posted By: JOD
Originally Posted By: 4ever4d
I really don't think that Caterham is pushing thin oils because he's a government plant trying to ruin our engines.....
it's the ones you least suspect...
seriously, I discovered this forum when I bought my Freestyle about 4 years ago. It was spec'd for 5W20, and I'd never even hear of this grade! Local stores didn't carry it, and I had a long succession of euro cars, Volvo's and some other "V" brand that I've banished from memory. The thinnest oil I had used previously was 10W30 in my CRX in the dead of winter, and even that made me nervous.
Fuel economy is of zero concern WRT my oil selection. While oil viscosity may matter on the macro level for FE, on an individual level it's a minimal difference. I'd us 0W40 in a heartbeat if I thought it offered more protection. I learned enough on this site to realize that the thinnest suitable oil is going to make for the least amount of wear, and that's why I use it.
No I'm not a Gov't plant.
I'm against Gov't intervention generally and I think CAFE was/is the wrong approach. My position has been to raise taxes on gasoline in the States and let the market place sort things out as to who makes and ultimately buys the most fuel efficient vehicles. This accomplishes two things; lets the market place encourage the sale of more fuel efficient vehicles and reduces the US trade imbalance and deficit on imported oil particularly from politically unstable regions of the world.
Regarding my pushing light oil. Fuel economy is not a big concern of mine; power is, driveability is and minimizing wear is. I used to be a heavy oil guy years ago, running straight 50wt and 60wt oils in British bikes and 20W-50 and 5W-50 in my cars. So I'm very familiar with the perceived benefits of running heavy oil and the problems.
The sole benefit of heavy oil is maintaining an adequate viscosity when oil temp's are very high and you're hammering it.
So the question is, what oil temp's are necessary for any oil grade to acheive an optimum operational viscosity that will minimize engine wear? Even with a light 50wt like a GP III based 5W-50 you will need oil temp's of at least 130C to thin the oil out to an optimum viscosity for most engines. A 40wt, around 120-125C. A typical 5W-30, around 115C. A 20wt, 95C to 105C.
So unless you're routinely see these oils temp's for the grade you're running you're not benefiting in any way from the higher protection level that oil potentially has to offer. But what's worse is that you have to live with the numerous disadvantages of running the heavier than necessary oil.
Even the lightest 0W-20 oil you can buy is still too heavy until oil temp's of at least 80C is acheived. And most engines, even in the summer months don't see oil temp's over 95C.
