Oil type/change frequency

[catahoula lou]

A neighbor of mine has a 1964 356C and is unsure about type of oil and change frequency. A mechanic I know claims that air-cooled engines are designed to use mono-viscosity oils, as opposed to multi-viscosity oils, with either having an appropriate amount of zinc.

Questions:

(1) Is this true?

(2) Given that his engine is now a true 356 engine (w/oil filter), how often should he change his oil/filter, considering that he lives/drives in the mountains?

(3) He used to do oil changes every 2-3K miles in the temporary VW 1600 (no oil filter) engine that he used until getting the Porsche engine. If he adds an oil filter to this engine, does that mean he can now increase mileage between oil/filter changes, in case he needs to swap back for some reason AND would that be the same frequency as the Porsche engine?

Best,

Thom

[930cabman]

I have been using 10w 30 and 20w 50 (depending on the season) for my Porsche's for many years. Generally change 2500 to 3000 miles with the by pass oil filter. No reason to over think a simple thing. Maybe in extreme conditions "newer" additives would be required to compensate for the change in automotive chemistry.

Currently our '64 SC runs on premium gas with an annual oil change, no muss/no fuss

[The cap'n]

Back when multi grade oils were less than perfected, Porsche recommended a straight 30w oil. Many of us used oils with a pretty high detergent capability. Oils such as Shell Rotella were popular. In the early to mid 70s multi grade oils were approved for use in 911s and 914s and 356 people began to use them. 20w50 is a pretty good choice for moderate to hot climates. I live in such a climate and have little experience with lighter oils in air cooled Porsches because it just doesn't get cold here. Oil and filter changes coincide with valve adjustments, every 3000 miles. If you don't go that far in a year (shame on you), change it once a year. If you have to resort to that strategy, be sure those times you drive the car include a half hour or more of fully warmed up operation at speed. Keeps the condensation down and helps keep the oil happy.

The Cap'n

[id10t]

20w-50, real dinosaur and not synthetic. Trickiest part is getting the correct gasket for the top of the filter cannister. I use Napa 1010 Gold filters, right size gasket and work great. Cheap too. Most farm places should carry them, they cross over to an older ford tractor.

[Les Paul]

Originally Posted by id10t

20w-50, real dinosaur and not synthetic. Trickiest part is getting the correct gasket for the top of the filter cannister. I use Napa 1010 Gold filters, right size gasket and work great. Cheap too. Most farm places should carry them, they cross over to an older ford tractor.

Amazing. Good to know that after all these years. I'd been making my own gaskets because 99% of the ones I got were to big.

[The cap'n]

If you buy the German filters, the gaskets fit.

The Cap'n

[Miguel Antonett]

^^^I order my oil filters though AutoZone - delivered to the house as special order, never had a problem with the gasket.
Regarding the oil, I use BradPenn 20 ~ 50 and change it when it goes from green to "black/dark", which takes around 2K miles.