I changed the oil almost 1 year ago in my Iroc (86,000 miles) with mobil1 high mileage. I've put 1000 miles on the car since then. Some say change it , some say wait. any opinions? Oil is cheap.

 

I think you answered your own question. Oil is cheap and easy to change, but the damage that old oil can cause on a engine can be expensive. You can never go wrong with some fresh oil and a new filter. Just my honest opinion. Good Luck!

 

Well, in my humble opinion, I'd wait... I have a few cars that sit for years at a time with dino oil and low run times with no ill effects.. Synthetic should be even better for the long haul, as long as it still looks clean.. But, if you feel the need it won't hurt it to freshen the oil in the pan.. As with advertising, Your results may vary...

 

I'll just do it. Can't hurt. thanks

 

Oil accumulates exhaust residue from running.

The combination of carbon dioxide and water, which are the natural results of complete combustion, create an acid. Highly corrosive. Same thing as soft drinks. Go find out what happens when you dip something brass or copper or un-anodized aluminum in Coke for a month or 2.

Running the car for short times, i.e. where the oil doesn't come up to its full operating temp (225 - 250° more or less) and stay there long enough to boil all that crap out of itself, leaves all that acid in the crankcase.

The acid EATS the bearings and other critical engine parts.

Follow the marine engine mfrs' recommendations. Change the oil at the end of the season, to get the acid out of the crankcase. Don't let the engine sit around with used oil, especially if (like a garaged pretty-day car that gets started once every coupla months) it never warms up and STAYS WARM long enough for the oil to keep itself clean of that crap.

 

I change my camaro and Boat engine oil once a year even if it only has a few hours on it.
For the cost its good insurance. Having said that I have not changed the oil in my plow truck in 5 years. I just add a quart and change the filter every few years and she starts, runs perfect.
For something you care about change it.