I put the wrong oil in!

[Yella Fella]

It should have been 10W 40 but I must have picked the wrong grade up by mistake and put in 15W 40.

I'm assuming there is no real concerns, other than the engine taking a bit longer to get up to temperature?

I'll put the correct grade in before the winter sets in. Until then, should I have any concerns?

[murphyv310]

No problem Glenn.
The biggest concern would be if it was a low spec oil. The 15 is the viscosity when cold so marginally thicker, may give a slightly worse fuel consumption if your doing short runs but I doubt you'll tell difference.
I'd be leaving it till the next oil change.

[MrDoodles]

Unless we have a really hard winter, the difference in viscosity is so minimal, I doubt anyone on here, would be able to tell the difference!

[Yella Fella]

I thought it would be ok but needed someone else to confirm.

Of course I only noticed after I put the oil in, silly me.

[Dorset Bob]

It will be the correct viscosity at normal operating temperature.
I suppose it depends if you are doing lots of cold starts with a cold ambient temperature.

These are viscosity curves, from 0 degrees C, on 0w, 5w, 10w and 15w40 Mobil 1 oils, as an example.
As you can see there the difference is negligible once the engine starts to warm up, but more apparent when at freezing point, or below.



I think that if you put the correct grade in before winter sets in, and are not doing short runs, it should be fine.

[chrissyboy]

i would take it out its the wrong oil end of .Use only what the owner's manual specifies. Using the wrong oil can lead to reduced lubrication and shorter engine life.

[minimutly]

chrissyboy i would take it out its the wrong oil end of .Use only what the owner's manual specifies. Using the wrong oil can lead to reduced lubrication and shorter engine life.
Hardly. So long as its good quallity, it will be fine.

[Yella Fella]

Originally Posted by Dorset Bob

It will be the correct viscosity at normal operating temperature.
I suppose it depends if you are doing lots of cold starts with a cold ambient temperature.

These are viscosity curves, from 0 degrees C, on 0w, 5w, 10w and 15w40 Mobil 1 oils, as an example.
As you can see there the difference is negligible once the engine starts to warm up, but more apparent when at freezing point, or below.


I think that if you put the correct grade in before winter sets in, and are not doing short runs, it should be fine.

Originally Posted by chrissyboy

i would take it out its the wrong oil end of .Use only what the owner's manual specifies. Using the wrong oil can lead to reduced lubrication and shorter engine life.

I will be putting the correct grade in before the temperatures start dropping. If I get the opportunity I'll do it this week before my wee touring break around the Lake District next week.

[murphyv310]

Hi.
Remember that 0W is the viscosity of water. There is a school of thought that thin oil looses its protecting film over night and initial start ups are dry, whereas higher viscosity oil retains just that little bit more. Don't get paranoid it'll be fine. We also don't live in Siberia!

Another way to look at it, short runs can increase the oils viscosity as there are chemical changes with condensation and other contaminates, so your old oil was probably thicker than your new oil.

In a cool running diesel engine fuel can dilute the sump oil too, when warm(ish) the upper viscosity rating can then be depleted.

[FROGGY]

Oil is oil is oil.
I can remember the days when you bought oil or oil.
Nowt's going to explode, too much **** about now about use this that or the other.
Change the stuff every 5000 miles, don't really matter what you put in.