Road Rage

It rarely gets mentioned here that 5w40 is an approved visosity oil for our engines, if not "preferred". Preferred is meant to be the oil the car is certified with, and produces the lowest emissions/highest fuel economy.

5w40 is the majority of what European cars mfrs. specify these days, as it flows fast, has high enough vis for sustained high speed driving on the Autobahn, Autostrada, Nurburgring, Mille Miglia, etc. Plus, it is "green" enough for the envirocons which have strong political clout.

Many Euro mfrs. actually have oil performance specs, similar to GM's for the Corvette. This is true of BMW, Merc, Audi, VW, etc. They call them LL (long life) oils and they figure prominently in the extended drain interval computer algorithms. M-B allows for up to 20K OCI's (oil hange intervals)! This is the reason that when Mercedes USA allowed customers to use lesser oils (mineral based) in the US, accelerated wear occured, and Merceds ate over $30M in damages.

A 5w40 is exclusively a synthetic or synblend as far as I have been able to determine. There will be some VI improver needed to span the range needed to meet the spec, but the quality syns use HT/HS viscosity index improvers so sheardown is not a big concern.

Here are some of the best as of this writing:
Mobil Delvac1 5w40 (a diesel/spark oil with better additives than regular M1)
Red Line 5w40
***New: Amsoil 5w40 "European Car Formula" - it has additives in the 2000-3000 series range, which is Amsoil's best additive chemistry
Mobil 1 "Euro Formula" 5w40

TYPICAL TECHNICAL PROPERTIES
AMSOIL Synthetic 5W-40 European Engine Oil AFL

Kinematic Viscosity @ 100

xviper

This thread added to the "Oil Journals".

Asura

After switching to Redline 10W-40 to see if that would reduce the amount of oil consumption on my 'loose' motor. I do feel a marked lack of pep. My local Redline distributor does not carry the 5W-40. I would try the Delvac, but the anti-Mobil sentiments coming from under my hood say otherwise.

I'll order the RL 5W-40 and see how it fares.

Boston Duce

Just to add to the 'Euro' OCI mindset;

My MB 'gararge queen' service indicator extends OCI to 2 years. Other MB's I've had went about 10K in "normal" driving before the indicator went on.

MB says it's a "flexible" indicator able to call for changes up to 12k mi., and it can "read" the oil's condition real time--optically I think. The MB dealers will not change the oil under the "free service" program before the reminder goes off. I remember getting a urgent letter from MB about using only "fully synthetic" oil for all oil changes or they would void the warranty. Dealers arround here generally use Mobil 1 0-40, but I've had one put in Castrol Syntec 5-50.

My BMW daily driver (wife's) has gone 7500 mi and no service indicator yet with 5-30 synthetic. I suspect that too will go about 10Kmi before calling for service.

Both cars came factory filled with synthetic.

Interesting that just about 10 years ago these manufactures were calling for a first service from 600-1200 miles and they would change both engine oil and diff oil at that time.

I find it hard to believe that these manufactures, responsible for engine warranties for 4 years and 50K mi, with a potential replacement cost of $50,000 (V-12 supercharged) would not do a LOT of thinking about, and testing the longer OCI. They seem to be saying that 10k mi or 24 months is ok for a "synthetic" OCI.

OCI's seem to be like baseball and religion, full of myth, tradition, and mystery.

Regards,
BD

Tugz_S2K

BTW....even though it is started in our Owners Manual, Honda Canada does not reccomend the use of 5W40 in our cars here in Canada.

Road Rage

[QUOTE]Originally posted by Boston Duce
Just to add to the 'Euro' OCI mindset;

My MB 'gararge queen' service indicator extends OCI to 2 years. Other MB's I've had went about 10K in "normal" driving before the indicator went on.

Road Rage

[QUOTE]Originally posted by Asura
After switching to Redline 10W-40 to see if that would reduce the amount of oil consumption on my 'loose' motor.

Asura

Mobil 1 was accompanied by excessive consumption and coupled with a 2-3 mpg decrease per gallon!

It you say it is superior, then I won't be biased by Mobil 1. Since you recommend it, I have not ruled it out. As an act of faith, I'll try it on the next change. Any online stores you recommend picking it up from? Part of the reason (minor concern) is that I would have to lug around the large container it comes in for routine top offs. That extra mass will surely add 1/10ths to my commute time

Ludedude

Maybe I can convince your distributor to get some 5W-40?

Asura

Might be difficult...he tends to have an unquenchable addiction to GF crack and speed. If he is ever conscious, he is usually playing poker at an indian reservation and betting the farm in exchange for a set of slicks. The only thing he is good for is domination of amateurs in U3. Other than that, he is completely useless.