5wXX vs 10wXX vs 15wXX on cold start protection

**Martz1977** · April 19th, 2013 11:03 PM

I read that delo400 is a really good oil in terms of engine protection since its loaded with additives and high tbn. But since its a 15w40, does it protect better vs 5w or 10w oils on cold starts knowing that engine wear happens during this time? Im inclined on getting delo400 right now but im not sure if the extra cost for 5w40 oil is worth it. Tnx

**rmsoriano** · April 19th, 2013 11:15 PM

Originally Posted by Martz1977

I read that delo400 is a really good oil in terms of engine protection since its loaded with additives and high tbn. But since its a 15w40, does it protect better vs 5w or 10w oils on cold starts knowing that engine wear happens during this time? Im inclined on getting delo400 right now but im not sure if the extra cost for 5w40 oil is worth it. Tnx

I think, AFAIK, the first number does not matter if you are using the engine oil here in the Philippines, di naman kasi nagwiwinter dito sa atin....

**Martz1977** · April 19th, 2013 11:30 PM

Originally Posted by rmsoriano

I think, AFAIK, the first number does not matter if you are using the engine oil here in the Philippines, di naman kasi nagwiwinter dito sa atin....

Sorry sir, But if its the case, why do we bother with multigrade? SAE 40 na lang kagad sana then lots of additives.

**niky** · April 20th, 2013 12:54 AM

Originally Posted by Martz1977

Sorry sir, But if its the case, why do we bother with multigrade? SAE 40 na lang kagad sana then lots of additives.

You've answered your own question. You buy multigrade specifically for cold engine conditions. And the lower the first number, the better suited it is for cold temperature starts, and the better it is for fuel economy (running cold with a thick sluggish oil results in poor economy).

You can even use 0w oil. What's important for hot temperature running (when the engine is warmed up) is the second number. A 5w40 would perform similarly (but not identically) to a 15w40 when the engine is warmed up. As always, check your manual to see what the recommended range is, before buying.

**Martz1977** · April 20th, 2013 08:34 AM

Originally Posted by niky

You've answered your own question. You buy multigrade specifically for cold engine conditions. And the lower the first number, the better suited it is for cold temperature starts, and the better it is for fuel economy (running cold with a thick sluggish oil results in poor economy).

You can even use 0w oil. What's important for hot temperature running (when the engine is warmed up) is the second number. A 5w40 would perform similarly (but not identically) to a 15w40 when the engine is warmed up. As always, check your manual to see what the recommended range is, before buying.

I know that that the last 2 digits would matter for normal operating temp. It was thoroughly discussed from other oil topics. However, i cant find any info on how soon a 5w or 15w oil properly lubricate an engine on a, lets say, 1.6 ltr engine. Are we talking about a few seconds only? If there is no significant diffrence, then is it more on fuel consumption during cold start up to normal operating temp?

**Martz1977** · April 20th, 2013 09:50 AM

Found this graph. Difference of 171 viscosity index for 5w vs15w *20C. Its still doesnt answer my question though on how fast oils properly lubricate during start up.

**rmsoriano** · April 20th, 2013 10:03 AM

Originally Posted by Martz1977

Sorry sir, But if its the case, why do we bother with multigrade? SAE 40 na lang kagad sana then lots of additives.

Maybe sir you are right, dapat SAE 40 na lang dito sa Philippines, but this is not what our car manual is telling us especially for new engine, maybe the Car manufacturer is just too conservative in telling us what oil to use here in the philippines, beside they don't even know in which part of the world that our car maybe used or exported. If you want to know how the first number and letter differ from each other in terms of functionality, the link below might help you,
[ame=http://www.youtube.com/watch?v=OWiQyR7PWII]esso engine oil winter conditions part 1 - YouTube[/ame].
But again, AFAIK, sae40, 0w-40, 5w-40, 10w-40 and 15w-40 oils will just flow in the same manner here in our country considering an ambient temperature of 30 degrees centigrade kahit pa cold start, kasi nga eh nakikita mo naman yung oil condition sa container nya with an ambient temperature here in the philippines, definitely, sa loob ng engine ay ganuon pa rin ang condition nya. Siguro nga ay sa additives na lang nagkakatalo ang different oil brands.

**niky** · April 20th, 2013 10:23 AM

Those oils do not flow the same at 30 degree centigrade. The "40" will refer to viscosity at operating temperatures, which are much higher.

Oils with a smaller first number will always give you smoother operation and better economy right after start-up, before the engine reaches operating temperatures.

**rmsoriano** · April 20th, 2013 10:35 AM

ok sir, thanks....

Originally Posted by niky

Those oils do not flow the same at 30 degree centigrade. The "40" will refer to viscosity at operating temperatures, which are much higher.

Oils with a smaller first number will always give you smoother operation and better economy right after start-up, before the engine reaches operating temperatures.

**MrQ5** · April 20th, 2013 11:21 AM

Originally Posted by Martz1977

I know that that the last 2 digits would matter for normal operating temp. It was thoroughly discussed from other oil topics. However, i cant find any info on how soon a 5w or 15w oil properly lubricate an engine on a, lets say, 1.6 ltr engine. Are we talking about a few seconds only? If there is no significant diffrence, then is it more on fuel consumption during cold start up to normal operating temp?

if lubrication is your concern at cold start, google oil filter operation as this really counts in flow of oil and engine wear and tear.