[cstavaru]

Hi,

I am replacing the BMW 5W-30 with Castrol Edge Sport 0W-40 shortly. I wonder if the higher viscosity oils cause higher fuel consumption ? What about if I want my engine to last a long time, is it better to stay with 5W-30 or is 0W-40 better ?

Thanks !

[328i]

Originally Posted by cstavaru

Hi,

I am replacing the BMW 5W-30 with Castrol Edge Sport 0W-40 shortly. I wonder if the higher viscosity oils cause higher fuel consumption ? What about if I want my engine to last a long time, is it better to stay with 5W-30 or is 0W-40 better ?

Thanks !

In theory 0w40 would provide better start up protection when the car is cold, but it's hard to say without seeing the specs of the actual oil. In fact 40 might be a bit too thick, and might cause poorer fuel economy. I see you're in Europe, I would actually recommend going with Castrol 0w30 where you get the best of both worlds. It's a thick 30w so it will offer great protection when warmed up as well. For keeping your engine lasting a long time, I think shorter drain intervals are more important than anything, along with filter changes.

[cstavaru]

Originally Posted by 328i

In theory 0w40 would provide better start up protection when the car is cold, but it's hard to say without seeing the specs of the actual oil. In fact 40 might be a bit too thick, and might cause poorer fuel economy. I see you're in Europe, I would actually recommend going with Castrol 0w30 where you get the best of both worlds. It's a thick 30w so it will offer great protection when warmed up as well. For keeping your engine lasting a long time, I think shorter drain intervals are more important than anything, along with filter changes.

Well...I think I will go with 5W-30 next time...if that's what BMW uses, I suppose it must be good

However, I read on the Castrol web site that the 0W-40 has an edge on better fuel consumption in a certain test. Probably compared to other 0W-40 oils though.

[ala012]

I think 0w-40 is more suitable for our turbo car. Especially when you wot alot, you will see very high engine oil temp (higher than 245F, 120C). 0W-40 will give you more protection on wot. I actually like Mobile1 0w-40 and Castrol Edge 0w-40. I prefer Mobile1 because I heard castrol changed the fomulation of their engine oil which results Mobile1 is better.

If you are in europe, I would highly recommend ARAL 0W-40 (Made in germany) !!!! This engine oil is designed for Turbo and Direct injected car. But it's more expensive than castrol and Mobile.

In US, every BMW except M uses 5w-30. 328,335 uses same engine oil in US bmw service center. You know my point ...

[F32Fleet]

Rumor is that the BMW 5w-30 is actually Castrol TXT Softec LL01 5w-30 and I can't find the PDS on this oil since it's no longer sold (replaced by SLX??). Personally I would run the Castrol 0w-40 in a car equipped with N54/N55 if you're intending to run factory oil change intervals (10k mi +), and it's LL01 which covers you from a warrany perspective.

A best of both worlds might be the Castrol 0w-30. I don't know if they sell it in Romania, but it's a very popular LL01 oil in the US with the BMW/Audi/VW crowd.

Edge 0w-40: Pour point -53 degrees C, KV@40C is 79.3cSt, KV@100C 13.5cSt

http://www.castrol.com/liveassets/bp...syntec_usa.pdf

[cb1111]

Originally Posted by TrackRat

Just asking but how do you know that 0w-40 oils "are more suitable for our cars" and that they "will give you more protection at WOT"? Do you have any objective scientific test data to support these statement? Does this apply to all 0W-40 oils? Does this apply to all engines or just non-M BMW engines? Does this apply to just turbo and direct injection engines?

When it comes to engine oils there seems to be a lot of unsubstantiated opinions but little published objective scientific test data for people to make an informed decision. Thankfully car makers like BMW and other Euro car makers test oils and certify the oils that actually meet the engine's lubrication requirements.

As far as wear and mpg, the U.S. BMW gas engine warranty from 2006 onwards requires the use of a BMW LL-01 approved oil of 0w-30, 0w-40, 5w-30 or 5w-40 viscosity for non-M engines. That means any of the LL-01 approved oils of this viscosity should provide excellent service, i.e. good wear and mpg. In actual use, you'd be hard pressed to measure the diff in mpg between a 5w-30 and a 5w-40/0w-40 oil especially when studies have shown that personal driving habits can change the mpg as much as 30%.

Good point - OTOH, my maple syrup/Paulaner blend increases gas mileage by at least 100% - based in part on the its Kung PAO chicken base.

Why do people always want to second guess the people that designed the cars? Conspiracy theories aside, they have a vested interest in assuring that their cars run well. They want your repeat business.

[F32Fleet]

Originally Posted by cb1111

Why do people always want to second guess the people that designed the cars? Conspiracy theories aside, they have a vested interest in assuring that their cars run well. They want your repeat business.

The OP isn't. He's merely comparing one LL01-oil over another.

[AlanAZ]

I went from factory 5W30 to Mobil 1 0W40 and did not notice a change in fuel economy.

[Dackelone]

I have a US spec car here in Germany. I only use Esso SuperPlus 98 octane low sulphur gasoline.

The only thing I noticed when I switched from the US spec Molil-1 0W40 LL-1 to German Castrol S Edge 0W40 LL-4, was on cold starts, the engine sound sooo much quieter! The ticking noises were MUCH less evident with the German Castrol than with the US Mobil-1. No differnce in gas mileage. Its still in the gutter!