5w 40 - 10w 40 will it really matter ?

[princeperch]

So as some of you know, the other day, I had the oil changed in my car. We shall draw a line under whether I got a good deal or not!

https://www.daciaforum.co.uk/forum/topic/5660-how-...

This chap here has the same car me as with the same engine, and he was told by Dacia to use 10w 40 oil - indeed he purchased the oil from them. It's the same oil that I used for my oil change.

I happened to read elsewhere that really you should use 5w 30/40 i.e a slightly thinner oil with these 3 cylinder cam chain engines. If I had known about that, I probably would have used a slightly thinner oil.

Whats done is done however my question is, will it really matter for the next few months ? I don't really use the car all that often and only do 4/5000 miles a year. I don't care about any difference in mpg - I'm more worried about the cam chain stretching etc.

Any thoughts?

[Tyre Smoke]

You'll wreck the engine within 100 miles.


No. No you won't. It will make absolutely no difference whatsoever. Just forget all about it and enjoy driving you Dacia.

[steveo3002]

the 5w would crank over easier in -30 deg weather , wont make much odds in the uk

[princeperch]

So the lubrication properties of the thicker oil won't be inadequate for the cam chain?

I wouldn't say I enjoy driving my Dacia although it's the most useful car I've owned. I have a very lovely MK1 mx5 when I want to enjoy driving. The only problem with the mx5 is that I cant fit a 2.5m 250kg olive tree in it or dismantle a kitchen and take it to the tip.

[steveo3002]

will be much the same at normal uk temps , im sure theres a chart somewhere but the 5w would just circulate better at savage freezing conditions , not a frost but extreme cold

dont worry about it .

[steveo3002]

heres a chart...see its suitable for even colder temps

https://www.motorstate.com/oilviscosity-htm/

[Baldchap]

steveo3002 said:

heres a chart...see its suitable for even colder temps

https://www.motorstate.com/oilviscosity-htm/

Didn't actually know what the exact ratings meant. Good chart, thanks (not OP).

[GreenV8S]

princeperch said:

So the lubrication properties of the thicker oil won't be inadequate for the cam chain?

It's only the cold rating which is different. Being slightly thicker when cold will make it a little harder to crank but unlikely to cause engine wear related problems.

You may find the narrower multigrade rating is a better oil overall since it will not have needed such extreme measures to achieve the viscosity range.

[princeperch]

Thanks all, appreciate the replies. Some of the blokes on the Dacia Facebook group seemed to think the cam chain was going to lunch itself due to the "wrong" oil being used..

[stevemcs]

Does it meet the Renault spec ? In all honesty the only ones that really matter are the low ash oils for diesels

[Tyre Smoke]

princeperch said:

Thanks all, appreciate the replies. Some of the blokes on the Dacia Facebook group seemed to think the cam chain was going to lunch itself due to the "wrong" oil being used..

Nasal adenoidal sock and sandal wearing types unnaturally enthusiastic about the purchase of their first brand new car, probably.

My Cerbera had a big sticker under the bonnet recommending Mobil 1 0-30. It clattered like a bag of nails until I put Millers 10-40 in.

[Evoluzione]

https://www.youtube.com/watch?v=IKdhgKUZhPA

[Inline__engine]

it is not 1980's almost any oil will work fine for an econoboxx

[princeperch]

Is there any truth whatsoever in the Dacia men's assertions that these little tce cam chain engines are extremely sensitive to thicker oil being used ?

I mean it's not a major deal for me to use a suction pump and take out the thicker oil and replace with the thinner stuff but based on what you chaps have said above I'd be wasting my time and money.

[E-bmw]

All it means is that the oil won't get quite as thin in extreme temperatures that it will likely never get to in this country, not a problem.

ETA.

EG.

5/40 - (-35) to +40 deg C
10/40 - (-30) to + 40 deg C

Edited by E-bmw on Saturday 21st November 09:47

[princeperch]

E-bmw said:

All it means is that the oil won't get quite as thin in extreme temperatures that it will likely never get to in this country, not a problem.

ETA.

EG.

5/40 - (-35) to +40 deg C
10/40 - (-30) to + 40 deg C

Edited by E-bmw on Saturday 21st November 09:47

Cheers. I understand that now. It seems the concerns articulated by others is that the thinner oil protects the engine from cam chain stretch than the thicker oil. I won't bother to change it I think.

[Evoluzione]

There could be some reason for it which is peculiar to that engine. Maybe it's an oil fed tensioner which requires a certain viscosity otherwise it over tensions the chain. If that is the case then change it

[Coin-Slot]

Frequent oil/filter changes matter far more than the difference between 5/40 10/40.

[princeperch]

I actually contacted the bloke who did the tutorial in the Dacia forum link above and who used the 10 40 oil. He assured me yesterday that the 10 40 oil was supplied by the Renault garage and that it's acceptable to use for the engine.

[steveo3002]

ah good , so everyone was right then

if you want to look after the engine , change the oil on time and keep the revs down until theres heat in the engine , red lining it up the road when cold will do more damage