HOXXOH

When the GM desert testing was still done in Mesa, AZ (until 2009) some of the data for the OLM included the time from a cold start to an unknown oil temperature as a factor to be used in the algorithm. I don't know the details, but it was recorded due to the high rate of wear that happens during that time period. It had no relationship to a calendar, since it was merely minutes.
I'd guess that sort of testing has continued at the Yuma facility as the engines have evolved. IIRC, the wife's '08 Caddy STS (3.6 DI) had a recall about 2010 to revise the OLM, due to a camshaft oiling issue. At least that was the dealer's story.

05 Wreck

I would be more concerned about the PH levels of the anti-freeze as opposed to the oil change intervals of a car 13yrs old and sat most of it's adult life.

C6_Racer_X

The LY7 and LLT "High Feature" V6's had all kinds of issues with oil and the cam phasers for the VVT features on those engines. Most of the issues were that buyers of the more mundane vehicles with those engines didn't keep the "high performance spec" oil in them, and conventional oils didn't work so well in the VVT cam phasers, especially when the oils broke down (and the OLMS was calibrated for full synthetic oils, not conventional/cheap bulk oil).
Coolant is another thing that should be changed regularly in any car that isn't driven much. DexCool or Universal Long Life coolant, every 5 years (or 100K miles). Most early year C6's should be on their third fill of coolant by now.

Brake fluid should also be changed frequently, every 2 to 3 years is best.

S.C. vette

2x per year = Peace of mind

Turbo6TA

My 2011 GS is my 2nd car, so it gets only about 2,000 miles a year put on it. The car now has 17,000 miles since I purchased it new in 2011.

Since I live in south Florida, the car is not put up for winter. It's driven lightly year round.

I have been changing the Mobil 1 in the engine every year, but I really have 2nd thoughts about changing out full synthetic oil with only 2,000 miles on it.

Jeeze ... even straight 'dyno' oil we used in our late 60s muscle cars back in the day would go 3,000 miles between oil changes.

I am not believing that my 2,000 mile / 1-year old Mobil 1 oil is full of acids, and needs to be dumped at the end of only 1 year.

Yes ... I am still changing it at the 1-year mark, but the more I think about it, the more I think that this practice is a big waste of $$$.

Kenny94945

Follow up from above:

My recollection is that if the oil monitor was set and one year has past.
The computer has the dash screen indicate "oil change due".

I did not look in the serv. manual to confirm my memory.

The synthetic oil one or two year change time is a debate.
I think with syths and keep in a garage with mild year round weather, two year life is reasonable, yet just an opinion not fact.

Only a Blackstone Lab analysis can answer the time line question for sure as environments make each sample different.

Merry Christmas.

EVRose

C6_Racer_X

It was 3,000 miles or 3 months, and that was 4 times as often as yours with full synthetic.

It depends a lot on how you put 2,000 miles/year on your Corvette. If you drive it 40 miles a week (one round trip, 4 miles each way, 5 days a week, with it parked for 4 hours or longer between each direction), that's the absolute worst case for the oil. That could easily exhaust the pH balancers in your oil in under a year. If you take one trip of 150-200 miles total, maybe in two legs of 75-100 miles, once a month, that's fairly gentle on the oil.

There is a "margin of safety" built into the recommendations. You'll never harm the engine following the once a year schedule. If you go longer, you'll be getting closer to the real limit. Most people think there's at least a factor of 2 margin of safety. I'll agree that a margin of safety is likely, but I wouldn't assume to know what that margin is without actual documentation (which isn't published) or empirical testing on my specific situation. You might consider investing in a couple of oil analysis kits. Wix 24078 is available at local parts stores and on Amazon. Blackstone labs ( https://www.blackstone-labs.com/ ) also offers test kits online. It's $28 for the analysis, but they'll send you the "kit" for free. You pay when you send the sample in.

You'll need either a mighty-Vac pump or some way of siphoning oil up the dipstick tube, or you'll need a valve installed at the drain plug to draw samples. I prefer using my mighty-Vac to draw it up the dipstick tube. Seems cleaner with less chance of contamination from dirt around the plug/valve area. Watch the pH for sure. I don't remember the specific elements that show for the pH balancers in the oil analysis reports. Perhaps someone on here can say for sure.

Tonylmiller

Change it now, then you will know. Change it every year if you do not run the oil life indicator down to 0%.