Do I really have to change my oil every year?

[Jeff A.]

I am a little embarrassed to admit, but I did not drive my 66 this year.
Did start it a couple times, and let it get to operating temp.

I use a trickle charger, and the fuel has a dose of stabilizer.

My concern, since the oil still looks new - do I really have to change the oil and filter every 12 months?

And what about the older oil I have been stocking - is it still OK to use?
Is there a shelf life for oil?

Kinda thought I was smart, with the whole zinc thing - now I wonder?

[Tom H.]

Re: Do I really have to change my oil every year?

My opinion is you don't have to change the oil every year just to leave it sit again for another year. If it looks good, let it go. Your oil on the shelf should be fine.

[Richard M.]

Re: Do I really have to change my oil every year?

My opinion is you don't have to change the oil every year just to leave it sit again for another year. If it looks good, let it go. Your oil on the shelf should be fine.

I agree......and the oil on the shelf is a few million years old so another year or two shouldn't hurt.

The other thing I'd be concerned about is the anti-corrosive properties of the antifreeze/coolant. Cars that sit a long time loose the chemicals in it(whatever they are), to protect the internals. It would be nice to be able to measure that somehow. Maybe there is but I have never heard of it.

Rich

[Jim T.]

Re: Do I really have to change my oil every year?

I agree......and the oil on the shelf is a few million years old so another year or two shouldn't hurt.

The other thing I'd be concerned about is the anti-corrosive properties of the antifreeze/coolant. Cars that sit a long time loose the chemicals in it(whatever they are), to protect the internals. It would be nice to be able to measure that somehow. Maybe there is but I have never heard of it.

Rich

What is the shelf life of antifreeze? I need to send this question to the manufacturers.

[Mike R.]

Re: Do I really have to change my oil every year?

Hi Jeff, there is no shelf life for oil in its original containers. Exxon recommends that oil in aircraft engines be changed every four months or 50hrs whichever comes first. The thought there is that the oil absorbs some moisture and changing it reduces internal corrosion.

As far as starting the engine and letting it run goes, it probably doesn't get the oil hot enough long enough to get the moisture out. In aircraft the recommendation is to fly the airplane for at least one hour after the oil reaches operating temperature.

I don't want to be an alarmist, just trying to put forth some info from an area where engines tend to sit around unused more than is cars.

Coolant has no shelf life if stored in original containers but its anti corrosive properties are "used up" protecting the metal in your engine. It should last longer with infrequent use since there is less corrosion potential at lower temperatures but it doesn't last forever.

BTW O'Riellys has gallons of Valvoline full synthetic motor oil on sale for under $20/gallon and there is a coupon offer for buy one get one free thus yielding a price of $2.50/qt for a full synthetic oil. I use Lucas' break in additive to protect the cam (it is a ZDDP additive).
Mike

I am a little embarrassed to admit, but I did not drive my 66 this year.
Did start it a couple times, and let it get to operating temp.

I use a trickle charger, and the fuel has a dose of stabilizer.

My concern, since the oil still looks new - do I really have to change the oil and filter every 12 months?

And what about the older oil I have been stocking - is it still OK to use?
Is there a shelf life for oil?

Kinda thought I was smart, with the whole zinc thing - now I wonder?

[Michael J.]

Re: Do I really have to change my oil every year?

As far as oil goes, here is a thread with the experts recommendations:

https://www.forums.ncrs.org/showthread.php?t=74499&highlight=oil+recommendations&uid=7896

[Ronald L.]

Re: Do I really have to change my oil every year?

There will always be more opinions on oil than total posts on a DB, the readers digest version says low cost, change it. If you got the engine hot, it should have volatized the h2o and you're probably OK. I have a car that now sits for a year at a time and the oil is fine. Motor now has 320,00KM an in pulling the OHC cover, the cam lobes look new, un worn.

The coolant on the other hand...

If you had a rusty system to start with the additives were consumed within weeks of the last time you changed it.

I do not know of a good additive, but keeping the cooling system clean of rusty crud is just as important. Recall, that the additive mix is supposed to balance aluminum, iron, and CU-Brass protection. There was a time in the late 70's that an imbalance caused extensive corrosion to the AL alloy engines produced in the early 70's.

So at a minimum if there was a good additive out there, put that in and run it up to temp for a hour or so to get it thoroughly mixed in.

Alternative is to drain it and recharge with new using distilled water. Do not short change this last step using distilled water.

[Patrick H.]

Re: Do I really have to change my oil every year?

Leave it alone.

The oil is no different than if you changed it last week and drive it about your garage when you went to wash and wax it if that "might have" been your next step. My recommendation is not to start them if you're not going to drive them, but that's another discussion.

If the antifreeze is about 5 years old you're near the end of its useful life but you can as easily change it in the spring as now. If it's closer to 10 years then you're way past due.

Patrick

[Jeff A.]

Re: Do I really have to change my oil every year?

I think I better flush the anti freeze in all my cars.
From now on - when the oil starts to look a little dirty dirty - Then I will change it. Not going to worry about oil that looks brand new.

But really... I think I better get that car out and drive it a bit.

[Jim W.]

Re: Do I really have to change my oil every year?

Leave it alone.

The oil is no different than if you changed it last week and drive it about your garage when you went to wash and wax it if that "might have" been your next step. My recommendation is not to start them if you're not going to drive them, but that's another discussion.

If the antifreeze is about 5 years old you're near the end of its useful life but you can as easily change it in the spring as now. If it's closer to 10 years then you're way past due.

Patrick

I agree 100% with the above post, But I'd be a lot more concerned with the Anti-freeze. The old green stuff isn't meant to live in your cooling system for all that long. I'd definitely would at least start the car, back it out and drain the Anti-freeze into a proper container and flush the system and then refill with fresh green anti-freeze. The oil is as old a subject as is the Corvette itself or as for that matter any automotive engine. So long as a oil that has a good additives and zinc content it can go a long way. Good luck, and if you want someone to drive your 66 for awhile, I'm available.

[Jim T.]

Re: Do I really have to change my oil every year?

Removing the drain plugs on both sides of the block help in giving the coolant system a good flushing.

[Michael F.]

Re: Do I really have to change my oil every year?

No, you don't have to, but I change my vette oil every years whether I drive it alot or not and it is good preventive maintenance

[William G.]

Re: Do I really have to change my oil every year?

Hello,

I'm always interested in learning new things and gaining new insight. The issue of draining anti freeze and replacing it is a knotty one. Trying to get the block drain plugs out on a 40 something year old engine can be a real problem. Anything short of removing them is going to result in a less than thorough job. There are available on the market test strips to check the pH of the anti freeze. Anything less than a pH of 9.5 is supposedly reason for concern and certainly any acidic pH (below 7.0) would be definite reason for changing. But I wonder if merely checking the pH would be sufficient to ensure that corrosion is not going to eat away at that expensive original aluminum radiator. Opinions?

Bill

[Terry M.]

Re: Do I really have to change my oil every year?

Since this thread has migrated from oil to coolant -- check out this idea. I am not sure if this works better with aluminum or copper/brass radiator -- or even if that makes a difference.

http://www.ehow.com/how_4564140_check-antifreeze-multi-meter.html

Here is a link for those more visually inclined:

http://www.youtube.com/watch?v=mBXZtfzHhig

[Larry M.]

Re: Do I really have to change my oil every year?

Since this thread has migrated from oil to coolant -- check out this idea. I am not sure if this works better with aluminum or copper/brass radiator -- or even if that makes a difference.

http://www.ehow.com/how_4564140_check-antifreeze-multi-meter.html

Here is a link for those more visually inclined:

http://www.youtube.com/watch?v=mBXZtfzHhig

I have used my multimeter to check the voltage potential of the antifreeze in my 1967 SB. Seems to work okay. At least I feel better.

Information on this was posted by Duke Williams and others a few years ago, and should be in the archives. EDIT: Posted by Duke on June 14, 2002. Title of thread was "Dexcool! Has the jury reached a verdict?"

For the record, I use Zerex G-05..... and still change every few years regardless of my multimeter results. My 43 year old, original aluminum radiator and heater core are worth the extra $$.

Larry

PS: Since my 1967 is a factory AC car, there is no amount of $$$$$ that I won't spend to prevent having to replace the heater core.