Spark Plug and Oil? Confused?

[Brucelee]

Originally Posted by Paul

0W-40 allows oil to flow quicker thus reducing wear at the time of start up. It's been said that 90% of wear occurs at start up, so 0W-40 is the best oil anywhere in the world.

Really, now do you figure?

[Paul]

The lower the bottom number (0W, 5W) the better the oil flows at start up.

I believe this is the latest TSB from Porsche:

http://www.wrightune.co.uk/downloads/approved_oils.pdf

[dcporsche99]

Ahhh Jim,

Always look forward to your wealth of information!

Will be doing my plugs sometime this Spring and was also thinking about purchasing some Iridium ones on Ebay. But now I feel more at ease in knowing that the differences are not as significant as many of us have been led to believe. Thanks Jim, will definitely stick with the usual---at least in this case.

Hey Paul,
Thanks for the link to the oil info! :dance:

[Brucelee]

Originally Posted by Paul

The lower the bottom number (0W, 5W) the better the oil flows at start up.

I believe this is the latest TSB from Porsche:

http://www.wrightune.co.uk/downloads/approved_oils.pdf

As a general rule, yes. However, to be precise, you have to check the actual viscosity at cold temp.

For example, the last time I looked, the Red Line 5w-40 actually had a lower cold viscosity than the M1 0-w-40.

That may no longer be true as these guys change formulas all the time.

[Rodger]

I pulled the original Beru plugs from my '99 Boxster back around 27K miles and replaced them with the Denso iridium plugs.

It drove exactly the same....absolutely no discernable difference.

[chgolatin2]

So what oil will my both cars be happy with, the Porsche S and the BMW 540? Should I just use 10W40, 5W40 or 5W30? The previous owner used 15W50 but the car was driven in an all summer weather condition "Florida" I live in Chicago, Illinois weather changes dramatically and on the winter I dont drive my Porsche just in the summer but from time to time I tend to turn on the Porsche and let her run for the occassional winter warm ups.

I would like to stick with the Amsoil brand of oil, they offer a few options 10W40 high performance, 5W40 european formula and 5W30 high performance. I would like to use the same oil on both cars.

Thanks to all in advance! Robert (Chicago)

[Brucelee]

Originally Posted by chgolatin2

So what oil will my both cars be happy with, the Porsche S and the BMW 540? Should I just use 10W40, 5W40 or 5W30? The previous owner used 15W50 but the car was driven in an all summer weather condition "Florida" I live in Chicago, Illinois weather changes dramatically and on the winter I dont drive my Porsche just in the summer but from time to time I tend to turn on the Porsche and let her run for the occassional winter warm ups.

I would like to stick with the Amsoil brand of oil, they offer a few options 10W40 high performance, 5W40 european formula and 5W30 high performance. I would like to use the same oil on both cars.

Thanks to all in advance! Robert (Chicago)

The Amsoil 5W-40 Euro is fine for both cars. Ditto the Red Line oil of the same weight.

I would NOT use the M1 0W-40 in the BMW as it tend to be a "thin" 40 wt oil and tends to get even thinner after 2K miles of so.