crw

oil - yearly or more frequent pending miles
brake fluid - every 2 years
transmission fluid?
front differential fluid (all wheel drive cars)/
AC oil/freon?

pp000830

Hi CRW,
My 1986 Carrera used little to no oil until 5K to 7K miles were on the fill. This led me to believe the additives that control viscosity are beginning to break down allowing the oil to begin to slip past the piston rings,
For this reason, 5K to 7K miles is when I change the oil on my 993.
Since oil is designed to withstand huge heat and pressure and is not prone to evaporation, I see no time limit as to when to change the oil.
A lot of discussion of oil is based on brand preference (advertising) or anecdotal evidence. These reasons hold sway, in my opinion, because an engine failure that can be directly attributed to using a specific oil is basically nonexistent.
Near the bottom of this page oil is discussed:
https://993servicerepair.blogspot.co...e-running.html
Andy