oil changes?

simon84 · Post by **simon84** » Tue Apr 04, 2006 11:28 am

How often would you change the oil in a car that isn't regularly driven. I've heard about oil deteriorating over time but how long does it take?
How about a seasonally driven vehicle that sits in winter?
Anybody got the dirt on changing out clean but old oil?

shogun · Post by **shogun** » Tue Apr 04, 2006 6:27 pm

it depends what kind of oil you put in the car, synthetics last a lot longer than mineral oils, and depending also how is it not used

brianp · Post by **brianp** » Tue Apr 04, 2006 8:03 pm

well, for our lawn tractor which sits idle all winter, they reccomend changing the oil and filter in the spring when you start to use it again, which doesn't seem like a bad idea. I haven't always done it though.

It wouldn't hurt!

hberdan · Post by **hberdan** » Tue Apr 04, 2006 9:25 pm

I think I would change the oil in the car if it has been sitting for the winter, even if it has seen very little mileage...why take a chance on some old, possibly deteriorated oil, when it's so cheap to change it, and the filter, too?
Before you change it, just get the car warmed up to operating temp first.
A seasonal change might even be a good excuse to add some Seafoam or a similar elixer to the oil and run it up, first--to clean it out-- and then do the change.

Fingers · Post by **Fingers** » Fri Apr 07, 2006 10:26 pm

I just park mine for the seasons (spring, summer and fall) when it is time for a oil change. I do start it at least weekly as it sits anyway. Then when it is required to be put back into service, I pour a bit of fresh oil in (just about 1/4-1/2 quart), disable the ignition system (if it has been awhile), crank it a bit, then fire it up. Let it warm up and change it.

But that is just me.

I have heard of people draining it before storing a vehicle, then filling it up before starting it, but I don't see any advantage in this.

I am not sure, but I would have to guess that oil sitting for a season is not going to break down a substantial amount.

Fingers

Paul · Post by **Paul** » Sat Apr 08, 2006 11:02 pm

I don't think the oil would deteriorate in an inactive engine, but condensation might cause some moisture contamination. How bad probably depends on your climate and whether garaged or not. If I was only going to change oil once a year, it would be after winter storage.

Typrus · Post by **Typrus** » Sat Apr 08, 2006 11:42 pm

It does deteriorate. I can't specifically explain the chemistry of it to you, but it does break down. Synthetics last longer as far as I know though.

simon84 · Post by **simon84** » Sun Apr 09, 2006 5:34 pm

Thanks for all the input.
I was asking with regards to a couple of vehicles besides the tercel which I change the oil each 5000km or so.
My old plymouth sits a lot and I've changed the oil maybe once each year or two. I started it last night after not running it for 3-4 months. It was a bit rough at first but then smoothed out. And when I moved it, no big oil or tranny leaks on the garage floor. Maybe one drop. I'll definitely do spring oil changes from now on.
The other vehicle is at work. An old 84 international diesel school bus.
That sits all winter and then gets a spring oil change. I guess an 84 is not that old but she sure seems tired.
Thanks again

Chris · Post by **Chris** » Mon Apr 10, 2006 5:39 pm

I would be more concerned about the deterioration of the fuel and the carb varnishing up as the fuel evaporates. Fill the gas tank and use a fuel stabilizer. Last time I looked on the oil containers there was not an experation date nor any indication of shelf life.

If you are concerned about moisture or a pH change in the oil due to use, change the oil before you park it and forget it.

I like Fingers' suggestion of disabling the ignition and cranking it before you put it back into service. What is not a good idea (imo) is to start it weekly. That's where most of the wear comes from....starting.

Soutthpaw · Post by **Soutthpaw** » Mon Apr 10, 2006 8:38 pm

doing a oil change before parking it for an extended time is a good idea. Use synthetic oil all the time too. it is not the oil itself but the byproducts of combustion that cause the oil to loose some of its lubricating ability. for example a bottle of oil on a store shelf for a year or two does not loose its ability to perform as intended. As also mentioned the Gas is much more of an issue than the oil is.

simon84 · Post by **simon84** » Mon Apr 10, 2006 11:41 pm

Thanks again.
That's interesting about the gas being worse than the oil. Had an old 78 corolla that sat and it's carb seized.
Cranking it over with ignition disabled, that's just to get oil moving around before firing right? After sitting for a month or more the plymouth usually takes a lot of cranking to get gas in there so it fires so that should cover that angle.

Fingers · Post by **Fingers** » Thu Apr 13, 2006 10:04 pm

Yeah Chris, you are right about wear occuring during startup (also letting an engine idle for extended periods is a bad wear thing as well), but I figure that if I was driving it, I would be starting it a heck of a lot more. Plus, running it for a bit each week (not just starting it and letting it idle) keeps everything from drying out (seals and such) and by bringing it up to operating temperature you can keep the moisture from building up in the oil. I would drive it occasionally, but that whole tranny-bad thing kind of hampers that whole luxury. Hopefully that will be resolved soon.

Fingers