Canadian Nissan Truck Club

What I want to know is, if you have your oil changed they mark down on the sticky to either change it when it hits a certain milage or when so many months are up. Well if you are not driving the truck as often but the time in months come on the little sticky do you really have to get it changed then? If you wait till the milage is at the number, are you potentially harming the vehicle in the long run?

The thinking behind that is that the oil breaks down over time. I'm not sure whether or not that applies so much anymore, as there's so many additive in the oil these days.

I do know, that synthetic oil would be beneficial in this case, as it does not break down with time.

I've switched to a synthetic oil for this very reason.

Since I work from home and the truck hardly gets driven, especially in the winter, I extend the time between oil changes. If I didn't I'd be changing the oil every 2,000-3,000 kms; 1,000-1,500 in winter.

I've always waited 'till the mileage was up. If the oil don't break down in the jug, how does it break down in the oil pan? I know heat and stuff cause it. But if it isn't running then it can't be breaking down any faster.
I was watching a program once that said even the cheapest oil you can get from the dollar store is good enough for at least 10,000Km's, I wouldn't chance it myself but you know oil companies won't tell you that.

Oil really doesn't "break down." It can't lose its viscosity, nor does it somehow become less effective just 'cause its old. What happens is it gets dirty. And it's the dirt you want to get rid of. It's a shame really, as the oil itself is still fine. I seem to remember reading somewhere that old oil is filtered and recycled - I'm not sure where it goes off to, though. You can't really burn it...

Anyway, I digress - it's the dirt you have to get rid of, and that's easy to figure out: look at your oil and see what colour it is. This is why I change my filter more than the oil, and since my chevy conversion filter holds about a litre, I figure I'm dumping a litre of new oil in rather periodically.


Scott

Well, I know with even the "High mileage" oils that they are pushing these days, even they recommend you change the filter.

The oil itself is still good, but the filter gets clogged and then goes into bypass mode, which just allows the oil to circulate through the system unfiltered...

I drive my truck so much that I never hit that 3 month threshold before the recommended mileage is up, so I change it as the mileage requires.

And considering how important the oil is to your vehicle, maintaining the oil is kind of a good idea...

What I find amazing is how heavy oil filters get. If you don't change them they get heavy like bricks... "Where'd all that crap come from?" I ask myself.


Scott

Scotto wrote:What I find amazing is how heavy oil filters get. If you don't change them they get heavy like bricks... "Where'd all that crap come from?" I ask myself.


Scott

Well, you have to think as well, that when you install it the paper filter media is not saturated with anything, it's dry and therefore fairly light.

When you take it off to replace it, it's now saturated with oil, AND contaminants from the engine...

I hear you though, there is a noticeable difference between a new one, and a spent one.

Of course, even the PREMIUM Nissan filter for the Xterra's isn't much bigger then a shot glass, so the weight difference isn't that much! It's just too damn small to be really noticeable!

Oil will still break down from little driving and more sitting. Our friend, internal combustion, has many bi-products such as water and acids that will break down the oil causing carbon, varnish and abrasives. Short trips are the worst and will cause a shorter oil life weather sitting or driving.

To try to answer the question. You need to check you oil. After the 3 Months or what ever the manufacturer recommends look at the condition of the oil. If its dark, change it. If not, keep going. If your vehicle has warranty you have no choice, you have to change it when you hit the KM or date. Its not worth saving a buck if a problem ever arose.

I change my oil at what ever comes first. Most of the time its mileage. Remember though that the oil does get contaminated from the fuel that was injected into the cylinders from engine shutdown and moisture in the motor. The gasoline will break it down and scar the cylinder walls causing the compression to drop. Also any contamination will mix with the oil and scar the journals causing a knocking noise as well.

I do mine every 3000 miles