Topic: Opel Says GM-approved 5w-40 is Fine for LNF... Thoughts?

[ChrisPrice]

Seen several threads insisting we should only use 5w-30/0w-30. Which is what Saturn and Pontiac told us to do.

To my shock, I was reading the Opel GT manual, and found that Opel approved 0w-40 and 5w-40 for the Opel GT. Page 171, to be exact.

http://www.christopherprice.net/explaining-why-the-opel-gt-can-use-5w-40-and-the-saturn-sky-pontiac-solstice-cant-but-they-really-can-3349.html

We used to only have Mobil 1 European Car Formula approved for GM-LL-A-025 (that and Saab sold an oil through dealerships, which may have just been rebadged from Mobil). Now there's dexos2 which supersedes it in 40 weight oils.

So... should we use 5w-40 in our aging Kappas? More specifically, when... aside from track days? I can see it having benefits when oil seals are starting to leak, but on hot days too, it should improve lubrication in aging engines.

Big question for me is if it should just become daily driver use at a certain mileage. I was afraid (like many) it would mess with VVT timings, but if Opel approved that oil weight... I think we can safely say now that it won't.

Surprised it's taken this long to stumble on it. Also, Opel GT's manual makes all other Kappa manuals bow in shame.

[ChrisPrice]

Just got word from Mobil that European Car Formula is being discontinued... you may want to grab it at Walmart while you can, particularly with a $10 rebate right now: https://apfco.net/secure/R8235W/Home/Entry

That means no more "cheap" GM LL-A-025 certified oil in the United States. Which means if you want to use Opel-approved 5w-40 in your Kappa LNF, you have to step up to dexos2. And none of the US oil vendors will certify their US 40 weight blends for dexos2 - so it's a crap shoot.

This is also bad news for Saab turbo diesel owners who have GM certification and need for 0w-40 LL-B-025, Mobil 1 ECF was the only GM-recommended oil out there you could drive to a store and easily get.



Edit: Looks like Liqui Moli has one 40 weight LL-B-025 oil sold with Amazon Prime today - http://amzn.to/1N04J0i (Mfg Page)

[Sly Bob]

You had me all excited about a rebate until I realized that it looks as though it's a US only thing.

[ChrisPrice]

You had me all excited about a rebate until I realized that it looks as though it's a US only thing.

It is, but no dice on 0w-40 Euro formula. Apparently Mobil had the remaining stock sent back. Every store has the newer/cheaper blend with the FS decal in tiny print on both sides. Dropped BMW LL-01 compliance too, so I certainly don't see it as an improvement... I think they just used a cheaper blend myself.

I'd still pay the extra and go with Liqui Moli 5w-40, but I have to wait for the extended warranty to lapse.

Stinks this is probably my last GM-era car I can even use 40 weight oil in. Opel has bowed to GMNA and is requiring 30 weight oil on most of their cars - in the dexos era. The diesels are the only ones they're approving for 40 weight dexos2 at this point, except for maybe Corvette.

Only way to find out if 40 weight is safe in newer GM gas engines, is to plug and pray. Not worth it in my opinion.

[Sol Asylum]

I don't understand, why do you feel the need to run 40w oil?

[ChrisPrice]

I don't understand, why do you feel the need to run 40w oil?

* For those with a tune, 40 weight might provide better long-term lubrication under high output scenarios
* Engine seal leak is almost certain to happen at some point, stepping up to 40 weight on my '03 Maxima saved me a head gasket replacement - stopped the oil leakage completely (and has for 20,000 miles and counting).
* Thicker oil may help compensate for engine wear internally as the engine ages, preventing cylinder failure
* Because Opel said we could after GMNA said we couldn't - there has to be some reason for the dissention amongst the ranks there

I'm probably leaving out a few reasons I thought of in the past, but I've pulled an all-nighter preparing for furniture to be delivered.

[TomatoSoup]

Further to SA's question...

First - to be clear - a high-mileage engine does not necessarily mean it has more wear.   A 200k engine that's only been run on long trips and/or has had regular maintenance (incl oil/filter changes with good products) can easily have less wear than a 50K motor run under "extreme" conditions (short trips, irregular maintenance, dusty/dirty conditions).

Having said that, just because an engine is worn, doesn't mean it needs thicker oil.  Larger tolerances (due to wear) are only an issue if full oil pressure cannot be maintained, in which case thicker oil might promote higher pressures and thus flow to all moving parts. 

So you only really need to look at your oil pressures to see if you really need thicker oils.  And by the way, at that point you really shouldn't bother to care whether you are using Dexos x or anything else, 'cos your engines close to the end anyway

[Sol Asylum]

I agree with what TS posts.

Additionally lighter oils are preferred because they are easier to pump through the engine and offer less internal resistance to the various components thus increasing the performance of the engine and boosting gas mileage.  I would guess those doing a tune don't want to do something to reduce performance numbers.

There could be all kinds of reasons why Opel says something different than GMNA, just because something is in the Opel version of the Kappa manuals doesn't mean it also applies to the North American Kappas.  Is oil weight even graded the same between Europe and NA?  There could be some sort of regulation over there that makes what we call 5w30 equal to 5w40 because the actual grade was say 5w35, I don't know.  What's the tolerance on oil weights?  North America covers a much wider environmental area then Europe the average temperatures could be significantly different between the two markets that would allow an engineering team to the make the determination differently between the two.  We don't know all the variables that they do when they make these decisions.

If you have a bad head gasket putting in thicker oil doesn't solve the problem your head gasket is still bad you just slowed down the leak.

[Critterman]

If I am not mistaken we have fairly low oil pressure pumps in our engines.  I would think that thicker oil would not move through the pump and by default the rest of the engine as well as a lower viscosity oil.

[Sol Asylum]

That could be true too.  The thicker oil could cause the bypass valve to open and then you would get less oil flow to the parts that need it.

[ChrisPrice]

These concerns are why I too avoided even talking to myself about using 40 weight oil. But there is no way Opel would approve the weight, if those concerns were present.

And yes, someone asked if 40 weight oil in EU is the same as 40 weight in the USA. It is.

This isn't the first time GM engineers have disagreed on oil. Holden approved conventional 6017M oil for LS2-based engines on the Holden Commodore (and G8/Caprice)... whereas Detroit says those same engines required more premium 4718M full synthetic oil.

I'm well aware in a gasket-leak situation that you are delaying a fix, not actually repairing things with thicker oil. At the same time, it can make the difference. If you get an extra 100,000 miles out of the head gaskets, odds are something else will take the car out of service.

But I would still use dexos2/LL-A-025 40 weight oil, no matter how bad off the engine is. No need to make a bad situation worse.

Monitoring oil pressure, however, is not a bad idea to base the decision... assuming there aren't any leaks. It seems like the LNF doesn't really need it on extended track days, but I haven't monitored oil pressure enough on my car... or used it at the track (voids the extended warranty). Gives me a good reason to fire up Torque (the app) and get my OBD2 on.

[Gentleman Jack]

I use whatever is on sale. Sometimes it's a 20-40 and sometimes it's a weird bottle 70-90, but my motor always seems to run the same. This little lawn mower is impossible to kill. I should try running it on round up instead of gas. I'd get twice the weed kill!

[Wartie]

I use whatever is on sale. Sometimes it's a 20-40 and sometimes it's a weird bottle 70-90, but my motor always seems to run the same. This little lawn mower is impossible to kill. I should try running it on round up instead of gas. I'd get twice the weed kill!

Are you at the Airport again???

[Gentleman Jack]

Wartie-

I sent you a text. Let's chat.

[elff]

GJ

I have some engines where I mix the oil in with the Gas
CRAAAAAAZY

[Sol Asylum]

What if GJ mixed the oil in with the round up?

[Gentleman Jack]

GJ

I have some engines where I mix the oil in with the Gas
CRAAAAAAZY

Yeah, that is unheard of crazy!

[Powermizer]

Thicker the oil the better period. Shear strength has everything to do with oil holding up under severe conditions. Of coarse a good additive package too. Big problem is getting the oil where it is needed on a cold start. This is where more wear  comes from than anything  else if everything else is where it should be, meaning not over heating, or over fueling or not getting to operating temperature.

[Rogue]

GJ

I have some engines where I mix the oil in with the Gas
CRAAAAAAZY

I used to have a car where the oil magically mixed in with the fuel all by itself. I used the car to fog the neighborhood during mosquito season. It was an old Triumph - I know, what other kind of Triumph is there? It was a blast to drive. Nobody ever tailgated me!

[Gentleman Jack]

Thicker the oil the better period. Shear strength has everything to do with oil holding up under severe conditions. Of coarse a good additive package too. Big problem is getting the oil where it is needed on a cold start. This is where more wear  comes from than anything  else if everything else is where it should be, meaning not over heating, or over fueling or not getting to operating temperature.

I'm betting my lawn mower runs fine with 90wt instead of 10-30