Old oil, how bad can it be??

[RetroSC]

I changed the oil in my 67S with Brad Penn last year, then life got in the way.. and I didn't get a chance to get the car out much. One run to a buddys place, maybe 15 miles.

So there's 15 miles on my 15 month old oil and I'm planning on taking the car out a few times this fall. So should I change it?

Thanks!

[engatwork]

I would think the oil would be fine.

[Nick Triesch]

Really, it is no different than being in the can...it's just in your sump instead. Your car should still go about 300,000 miles if you use it! Nick

[kilodawg]

I think it's the moisture that would be the major concern. I'm no expert but I've always been told 5K miles or 12 months.

[porsche930dude]

the moisture condnesates in the engine and dilutes the oil. Its kinda open to the atmosphere so that may have an effect on it. Sitting in a bottle its sealed. Still 15 months I think would be ok. I wouldnt stretch it more than 20 months or so. Depends how it looks. If it gets funny looking kinda foggy and stale smelling change it

[dshepp806]

Start fresh,..I'd load new stuff.

Doyle

[slow&rusty]

I have a few cars that seldom get driven my 911 included and I change the oil twice per year to just err on the side of "peace of mind". Personally if the oil looks like honey you are fine, but definitely change it after a few of your runs this Autumn.
Yasin

[AVDCAV]

You would have been done already"
Go to the garage turn on the radio "
And get dirty ,,,

[Drisump]

I hear the "oil is cheap but an engine is expensive" argument, but I'm of the belief that unless you left the car out for that period of time the oil is fine, after all you don't change transaxle oil every year regardless of mileage. The act of starting the car generates most of the condensation and if the engine is run a proper length of time, most of that moisture is vaporized, therefore a car that is stored in a decent place and not started won't build up a significant amount of condensation over 12 months. Cheers

[engatwork]

therefore a car that is stored in a decent place and not started won't build up a significant amount of condensation over 12 months

What he said.

[GaryR]

Originally Posted by RetroSC

I changed the oil in my 67S with Brad Penn last year, then life got in the way.. and I didn't get a chance to get the car out much. One run to a buddys place, maybe 15 miles.

So there's 15 miles on my 15 month old oil and I'm planning on taking the car out a few times this fall. So should I change it?

Thanks!

I would run the car the "few times" you mention and then change it (hot) just before putting her away again to get rid of any condensation that may be in there.

[RetroSC]

Thanks for the reply's! Oil still looks good and green, I feel a little better now taking that drive this weekend.

[RWebb]

one drive won't kill it

Manf.s do shelf date their products, suggesting it will not last forever. Moreover, car makers tell you to change after a certain time (as short as 6 months for a mid-1980s VW Vanagon) no matter what mileage.

It is possible that over time, some things react either among themselves, or oxidize with the air. Or maybe small particles can settle out.

Buffers will not be loaded up with combustion acids, other nasties from combustion will not be present, the oil molecules will not break down from high heat near rings & valves, and as per above there will be little water in it. THO any water that IS in it will have had plenty of time to emulsify.

Yes, oil is cheap - that's the bottom line, no matter the quantification of the above parade of potential horribles.

[stlrj]

Extremely toxic by now, so carefully drain into original bottles and mail to my address for suitable treatment asap.


Cheers,

Joe

[Joe Bob]

Run it to operating temp. Pull the cap and look for mayonaise. If it's foaming at the mouth like Byron being offered a trade....you have excess condensation.

Otherwise drive it like you stole it.

BTW, you may have some excess smoke at start up....normal.

[Brando]

Originally Posted by Joe Bob

Run it to operating temp. Pull the cap and look for mayonaise. If it's foaming at the mouth like Byron being offered a trade....you have excess condensation.

Otherwise drive it like you stole it.

BTW, you may have some excess smoke at start up....normal.

+1, this would be the best thing to do. BP is good oil and should last a lot longer than the generic 'performance' oils at your FLAPS.