Grigiocorsa

Dear All
I have a 1989 C4, which unfortunately I use very rarely (even though I think about it very often).
Last year I drove it for 1500 Km.
What kind of oil change interval would you recommend?
What kind of service and how often?
Please tell me what is your behavior in such circumstances!

Thanks
F
964 3.3 Turbo (gone)
964C4 (alive and kicking)

ilko

Once a year should be enough IMO. Make sure you bring the car to operating temperature every time you drive, however (8 o'clock on the oil temp gauge). That will limit any possible issues with oil condensation and sludge.

Bearclaw

Last year, I worked way too much and put about 2000 mi. on the car. Agree on the once-a-year change, that's what I do. When you do drive it, try to get in at least an hour's worth of operating time, so all of that 3 gallons of oil gets thoroughly heated and the moisture cooks off. I also use an upper-cylinder lubricant in the gas for good corrosion protection, and some gas stabilizer as well. 1500km/yr means your petrol ages in the tank for long periods.

ltc

I drive my 996TT way less than has been described above (actually sat 2 years at one point)....FWIW I always change the oil right before it goes into storage for the winter.

elbeee964

(...wondering where the guy is, who's signature line says something like, "the hours a Porsche sits, you can't get those back")

Bearclaw

Like most, he's probably at work, paying for the damn thing.
Idealism collides with reality.

TR6

Change the oil at least once a year regardless of miles. I do that with my TR6 and it sees about 500 miles in a year (some past years, less than 300 miles).

dfinnegan

Everyone is entitled to enjoy their Porsche they way they see fit.

Me? I'd be driving mine right now if I weren't working!

springer3

1 x year, although even at 5000 miles per year my oil still looks golden when I drain it. Also +1 on driving long enough to drive off the condensation that forms each time the engine starts.

dfinnegan

Golden? Seriously? I thought the additives in the oils made them turn black within minutes (or hours?) of engine use. Is this not the case?

ilko

That's what I thought too. But my Brad Penn is still green 3,000 miles and a few track days later... Maybe it's the ZDDP

TR6

My Swepco oil is purple.

springer3

Seriously. I avoid short trips, and always get the oil hot enough to drive off condensation. Keeping condensed water/acids out of the oil keeps it looking cleaner for longer. As the engine wears and develops blow-by, the oil will start to get dirty sooner.

Roygarth

Why should one change the oil every year if minimal mileage done? Does it go off? Is there a sell by date on the can like milk? Why not change it every 18 months or 2 years?? I don't understand!

TR6

Yes, the lubricating properties can become reduced over a period of time even if not driven often. Moisture can accumulate in the oil even if it sits without running the car which reduces its protective properties. Especially in a damp, humid environment. Also, as someone else mentioned, short trips and shorter running periods will break down the oil faster than normal. For example, if you run the car without letting it get up to full hot temp for a decent period of time, the oil will accumulate trace amounts of fuel in the oil from the blow-by. That fuel in the oil will lower the viscosity and reduce the lubrication properties. I've seen this proved in my Blackstone Oil analysis reports on my cars when they get run for short durations, especially in the cool season. Acids and other contaminants can also accumulate regardless of miles which will break down the oil.

Bottom line is, oil changes are cheap preventative maintenance. Why take a chance? I change mine more often than probably necessary, but I would rather err to the side of caution. I figure it can't hurt and can only help.