[TYPEII]

I've had the oil (Mobil 1 Synthetic) in my car for over a year now, I don't drive the car much, probaly about a 1000 miles since it was last changed.

Is it safe to leave the same oil in there or should I change it?
I am thinking since it's Full Synthetic, NO.
It's not like gas where it will go stale from collecting water in the tank.

What do you guys think?

 

[Avarice]

If I'm not mistaken its best to change it every 3 months or 3,000 miles?

 

[FutureX 2001]

3 months or 3k miles, which ever comes first...

 

[502 MotorSports]

3 months or 3k miles, which ever comes first...

yep

I wouldn't risk it. But that's me.

 

[Glen]

I change my oil promptly every three months regardless of mileage and I'm averaging 700-800 miles between changes.

Glen,
1991 LS
60,500 miles

 

[LPB]

If the vehicle is not a daily driver, and you drive less than the recommended interval, I would suggest that you change the oil every 6 months. This assumes that you periodically start the vehicle and allow it to reach operating temp.

 

[-Ravez-]

How much of that 3months/3k can you go over on a daily used car before it starts causing problems?

 

[Jetdoc]

The Manufacturer of the VEHICLE reccomends changing the oil every 7500 mi. under normal conditions. The manufacturer of the OIL reccomends every 3000 mi. The 3000 mile number was born in the 1950's or before when oil quality was poor. Todays oil is far superior to the 1950's oil standards. If you use good oil and a new filter 7500 miles between changes is reasonable.
I have a friend that works at Autozone headquarters in Memphis. He does a lot of their buying. He says the reason the oil manufacturers have not changed the 3000 mile number is strictly $$$$$$$. They and Autozone sell more oil. If they followed the manf. reccomendations their sales would be cut in half.
I try to change mine every 7500 mi. or 6 months. I don't reccomend going more than 12 months without an oil change, no matter how many miles you drive.

Jetdoc
92 Legend L
188k stock

 

[TYPEII]

Is there any SCIENTFIC Case studies out there that would support changing your oil every 3 months/3,000 miles, especially in the case that you don't drive the car that much. How can the oil get bad if I don't drive it, all it does is lube the engine when I start it up in the Winter season.

I can understand changing it if you drive the car under normal conditions.
The oil can't get bad or can it. I don't see a life shelf date on oils, especially synthetic ones. I don't see stores chucking their oil off the shelves in 3 months.

Where's a Chemical or Mechanical engineer on this forum?

To me it's not a big deal in changing my oil, just wanted to gain more knowledge that's all, plus it's puzzling me.