LDV

Wanted to get opinions from the mechanically inclined members...

Background: My 991 is due for an oil change in the Feb timeframe (time triggered 20k service). An oil change was done in Sept by the seller (out of the normal service cycle). I'm attending an Autocross event in Feb.

The question is...should I have the car service BEFORE or AFTER the Autocross event?

Thanks

Slantnose!

I wouldn't worry about it either way...just make sure it's at correct level.
What class?

c_Gio

My entirely uninformed opinion is do before.

LDV

CC11/SS07

LexVan

How many miles are on the September oil change? Any high speed or autoX events since then?

AutoX is not that hard on the car. Runs are short and speeds are not excessive.

If you're close to 5,000 miles, change before. If a couple thousand miles, change after the February event.

DE events would yield different advice.

LDV

2000 miles since the Sept oil change

LexVan

So by the time of the February event you're at 2,500-3,000 miles. Change it after the event with Mobil 5W50.

LexVan

You DO need a brake fluid flush before the event.

fastdiablo

Why 5w? Don't recall seeing Porsche recommend 5w.

LexVan

There are at least a 100 oils approved by Porsche that are "5W". Most are 5W40.

Mobil 5W50 is the only A40 Porsche approved 5W50.

drcollie

I've done hundreds of autocrosses since 1995. All you really need to do is clean out all the loose stuff rolling around in the car and pull the driver's floor mat unless it is really buttoned down, and go have some fun. Your brakes will never get hot enough to get to temp and you certainly don't need an oil service. Make sure the tire pressures are where you want them all the way around and no lug nuts are loose...you're good to go.

fastdiablo

Sorry, in the context of the 991, why 5w? Thought I read 0w was the recommended oil for the 991. Just curious.

todd92

Neither. An AX event is unremarkable for your car.

There is no 'time triggered' oil change at 20K miles. The oil was changed in Sep, so the next oil change is due this Sep or 10K miles, whichever comes first. You are anticipating your 20K service with 5 month and 3000 miles since the last oil change. No reason to change the oil again then. Your 20K service now consists of just a cabin filter change. You can get away with just changing the one in the trunk, the one in the interior doesn't get dirty. Just do this yourself.

Yes, you should flush the brakes before the AX.

extanker

above tells it all. most ax's are marked out in an empty parking lot with mostly sharp turns....doubtful you will get out of 2nd gear.

LexVan

There are only 3 Porsche A40 approved oil viscosities for the 9A1 motor in the 991:

0W40
5W40
5w50 (only Mobil)

With 100s of approved brands.

Your owner's manual will outline the recommended ambient operating temps for these different viscosities.