What oil?

[digger]

every time someone brings up engineers I always think about their structural or mechanical ones who developed our RACP, exhaust hub tabs, and rod bearing (early pre LCI cars, and of course BMW blamed manufacturing, which may have been true). There is engineering and then there is engineering within the corporate arena and sometimes, well..... lol.

My sentiments exactly.

[0-60motorsports]

After my Next oil change of Castrol Supercar i'll be switching to MOTUL 10w60 as its easily locally available where i have to import the Castrol.

[lemoose]

tl;dw but those recommendations take into remain consistent given higher piston speeds/loads across?

[oceansize]

I don't care about oil and I'm dumb so I just use 10w-60, but I will say every time someone brings up engineers I always think about their structural or mechanical ones who developed our RACP, exhaust hub tabs, and rod bearing (early pre LCI cars, and of course BMW blamed manufacturing, which may have been true). There is engineering and then there is engineering within the corporate arena and sometimes, well..... lol.

[IamFODI]

Not following either of bmw m or whoever came up with other guide blindly / as a blanket rule

We are blind.

[digger]

Option 3 being?

Not following either of bmw m or whoever came up with other guide blindly / as a blanket rule

[IamFODI]

How about option 3 that not following 1 or 2 blindly

Option 3 being?

[digger]

Two possibilities here. Either

1. These guidelines show that BMW M's choice of viscosity grade was way off base, implying that M's engineers were unaware of this longstanding industry-standard knowledge; or

2. The M division knew something we don't.

Which seems more likely to you?

How about option 3 that not following 1 or 2 blindly

[IamFODI]

More salt on the wounds, Sorry guys lol


My ACL STD, measured at .002



Here are some recommended rod bearing oil clearances for various oil viscosities:

.0015 to .0018 for 5W-20 or 20W

.002 to .0024 for 5W-30 or 30W

.0025 to .0029 for 10W-40 or 40W

.0030 to .004 for 20W-50 or 50W

.0041 to .005 for 10W-60 or 60W



Video below


https://www.youtube.com/watch?v=aB-lf4kokSQ

Two possibilities here. Either

1. These guidelines show that BMW M's choice of viscosity grade was way off base, implying that M's engineers were unaware of this longstanding industry-standard knowledge; or

2. The M division knew something we don't.

Which seems more likely to you?

[BL92]

More salt on the wounds, Sorry guys lol


My ACL STD, measured at .002



Here are some recommended rod bearing oil clearances for various oil viscosities:

.0015 to .0018 for 5W-20 or 20W

.002 to .0024 for 5W-30 or 30W

.0025 to .0029 for 10W-40 or 40W

.0030 to .004 for 20W-50 or 50W

.0041 to .005 for 10W-60 or 60W



Video below

[prostcfc]

edit: looks like this deal is over


I just got Castrol Edge 10w60 for $8 /qt from Autozone
The page shows $12 /qt, but it will have the lower price once you add it to the cart.

They will also give you free no-rush shipping -- not sure if there is a minimum for this, as I bought 24 quarts 😬

Is this the one? Sorry, new to the platform and pictures between sites certainly aren't consistent. I think it's part number 15E99B?

https://www.autozone.com/motor-oil-and-transmission-fluid/engine-oil/p/castrol-edge-full-synthetic-engine-oil-10w-60-1-quart/1151725_0_0?searchText=10w60

[elbert]

edit: looks like this deal is over


I just got Castrol Edge 10w60 for $8 /qt from Autozone
The page shows $12 /qt, but it will have the lower price once you add it to the cart.

They will also give you free no-rush shipping -- not sure if there is a minimum for this, as I bought 24 quarts 😬

[BL92]

I have been using Motul 300V 10w40 for about 10 years.

Could you provide more info? Interval changes ? Wear, Noises, RB condition, Oil pump etc etc

[BL92]

Most of it is; some of it isn't (sorry, Tbone).

Viscosity is the most important single aspect of a lubricant, so viscosity grade is very important. However, Tbone is right that you do NOT want to choose engine oil based on that alone because there are other differences that can matter.

The "TWS shears down to an xW-40" thing is many years old, based on rare occurrences, and even those cases it was often suspect (fuel dilution wasn't always ruled out). The factory oil's formulation has been updated several times since then and hasn't been shown to shear lower than xW-50 in years.

He's right that some of Red Line 5W-50's viscometrics are comparable to those of an old version of Castrol TWS. We don't know how that compares to modern formulations because not all the info is published.

He's right that one can't conclude cold start performance based on viscosity grade. It depends how cold you're talking about.

Red Line's products aren't lightly additized. Their race oils are light on detergent additives, but we're not talking about those here (hopefully). However, it's a VERY safe bet that Castrol/BMW's additive package is better suited for street use.

He's right that Castrol/BMW oil will be friendlier to cats than Red Line's (or basically anything from Penrite, from what I'm seeing), while retaining more than enough anti-wear properties that you don't have to worry about it.




The people who built this engine – the only ones who have a complete picture of what it needs – strongly advise sticking to the factory oil. This isn't like other engines, where they write a spec and say everything that meets the spec is fine; they're saying "you really should use this exact particular oil." And as BMW has gone back and back-specced more modern and thinner oils for so many of its older vehicles to simplify its supply chains, they haven't touched this one – except for that one time they released a confusingly worded bulletin and then immediately retracted it.

If you're going to insist on rolling the dice and deviating from that, at least stick to what your favorite lube manufacturer recommends. AFAICT, the only engine oil Penrite recommends for this engine is their 10 Tenths Premium 10W-60, and they actually go out of their way to say it's the only one you should choose.

Love your work, Brilliant write up, thank you

[ac427]

I have been using Motul 300V 10w40 for about 10 years.