Choosing correct viscosity for BMW M5 w/ S63TU 4.4L V8

[Bozman52]

It is not running that hot for the coolant to reach a boiling point if diluted.
Diluting coolant is standard practice on the track. I run in my BMW on track 10% coolant in summer as the track is at high altitude and heat dissipation is far more important. BMW runs cooling based on need. The more you push it, the cooler it will run bcs. DME will put the thermostat and water pump into effective mode. If you baby it, it will run hotter, as DME is putting water pump and thermostat in efficiency mode. The problem is heat over time. These engines are hot V, and any heat that can be shed off is a gain.
Audi actually recommends in the manual in S/RS models to run 10% if tracking a vehicle, meaning where extremely high temperatures are expected.

Your points about the coolant mix are intriguing. As it's near impossible to perform a coolant flush on this engine, it just isn't something I've thought about. Realistically, I'm not driving in a way that will overheat the engine, but the engine bay still gets incredibly hot, so anything I can do to bring it down a bit is an improvement. I actually installed turbo blankets (Funk Motorsports) about a year ago. They're the ones that wrap all the way around the turbos, not the blanket that just lays flat over everything. With the hot V setup of the engine, they were NOT fun to install. Absolutely no space in there.

I have come across a few guys who say to drive the car in sport plus mode exactly for the reason you stated about DMEs putting the engine into efficiency mode. I have tested this theory and can actually see the oil temps change a bit if I drive the car on the highway in standard vs sport plus mode. The temp is lower in sport plus, so I always put the car into that mode after she's warmed up properly.

 

[edyvw]

Your points about the coolant mix are intriguing. As it's near impossible to perform a coolant flush on this engine, it just isn't something I've thought about. Realistically, I'm not driving in a way that will overheat the engine, but the engine bay still gets incredibly hot, so anything I can do to bring it down a bit is an improvement. I actually installed turbo blankets (Funk Motorsports) about a year ago. They're the ones that wrap all the way around the turbos, not the blanket that just lays flat over everything. With the hot V setup of the engine, they were NOT fun to install. Absolutely no space in there.

I have come across a few guys who say to drive the car in sport plus mode exactly for the reason you stated about DMEs putting the engine into efficiency mode. I have tested this theory and can actually see the oil temps change a bit if I drive the car on the highway in standard vs sport plus mode. The temp is lower in sport plus, so I always put the car into that mode after she's warmed up properly.

Just detach lower radiator hose, and get some coolant out. Or what I do before track season, since I must run 50/50 in winter, is that I use turkey baster and pull out coolant out of reservoir, and make up with distilled water. I do that over several days until I get desired ratio.
I mean it is not magic bullet, but IMO, for those engines anything helps.

 

[TwoC400s]

I actualy emailed Ravenol and asked effectively the same questions I asked here. They weren't super responsive, and Germany ended up kicking me over to their UK entity. I was hoping for a technical person to respond, but instead got the Marketing Manager . As such, I've mostly dismissed his technical feedback, but I did also ask some questions about their "racing" fluids. Specifically, I wanted to know if they have a different detergent pack in them. Here is what he said:

Regarding our motorsport oils like REP and RUP: while they offer incredible protection under extreme conditions, they’re not really intended for regular road use. These oils are engineered for sustained high loads and temperatures in race scenarios. They also tend to have a reduced detergent/dispersant package, which can make them less ideal for long-interval, stop-start driving. Our road-focused USVO oils (like VMP) actually share some of the same base oil technology, but they’re designed specifically for real-world, road-going use — which makes them a better choice for a car like yours that sees fast road driving but not track abuse.

I'd like to think he's probably right about this stuff, as a marketing guy should be able to explain basic differences in their products, so I'm thinking to stay away from their racing oils. If I were going to do a track day, it may be good to drop some in, but perhaps not for regular oil changes.


I appreciate all your input, and the story from the Nulon tech. The longer this thread goes on the more I'm getting convinced that a Ravenol (PAO based) 5W-40 oil may be best for me. At least I can try it this oil change, get another oil analysis, and see how things look next year.

Yes, RUP may have a decreased detergent level (but it still DOES have detergents/dispersants) compared to the road going oils, but with such low mileage annually, I wouldn't be concerned about it. Especially if your main focus is on keeping you bearings healthy. I would prioritizes anti wear over anti-deposit.

The PAO/synthetic base stock in RUP or RCS should mean at you low milage that oil will still be in good shape after a long time sitting in the sump.

 

[LordNilesStandish]

Especially if your main focus is on keeping you bearings healthy. I would prioritizes anti wear over anti-deposit.

+1
This should be primary concern for such an expensive engine.

 

[Bailes1992]

I'd order some M1 5w50 X2 from Autodoc and call it a day. It has the same add pack as the much loved M1 0w40 FS, but is a little bit thicker.

Usually pick up M1 0w40 or M1 5w50 at 4 litres for less than £40 delivered from Autodoc.

You're going to get a lot of suggestions on here for oils we don't get in the UK.

Alternatively, I used to run Fuchs Titan GT1 Flex 3 in nearly everything. If you shop around you can find it at less than £30 for 5 litres or less than £100 for 20 litres. It's a stout 5w40 with a mid SAPS add pack that carries a ton of manufacturer approvals (not just "Meets and Exceeds") including BMW LL04, Porsche C40, MB 229.52 etc.

 

[1JZ_E46]

Awesome car you have. I have had many BMWs over the years. Personally, I would run Castrol 5W-40 Euro A3/B4. Strong additive pack (you can find VOAs here) and it carries all the proper certifications... LL-01, Porsche A40, MB 229.5, etc. A "0W" oil is unnecessary.

 

[LordNilesStandish]

Awesome car you have. I have had many BMWs over the years. Personally, I would run Castrol 5W-40 Euro A3/B4. Strong additive pack (you can find VOAs here) and it carries all the proper certifications... LL-01, Porsche A40, MB 229.5, etc. A "0W" oil is unnecessary.

Do you Brits get the 0W40 Edge 'Supercar'?

 

[Hohn]

Q1: LL01 oils have greater buffering capacity for fuels which are higher in sulphur. Sulphur was lowered so DPF/OPF could be used to clean emissions. For all *intents and* purposes LL01 and LL04 have the same performance requirements so can use either obviously. Intake deposits haven't been a thing with BMW DI petrol engines for over 15 yrs and ran LL01 and later LL01fe in the US. Valves at 100k miles exhibit nominal buildup.

Q2: No difference in your climate. The biggest difference will be in HTHS. The 40 grades will be around 3.7 or higher and the 30 grades will be between 3.5-3.7. (Assuming LL01 or LL04).

Your engine just runs hot so you want avoid that 2 yr / 24k miles interval I've read about in the UK. Maybe change lesser of 1 yr or 5k miles and keep it stock.

The S63 is a crazy piece of engineering. GL and have fun with the car.

Please forgive me.

 

[Bozman52]

Do you Brits get the 0W40 Edge 'Supercar'?

I just searched for this and it does not seem to be widely available. There were some obscure places that seem to sell it, but it may be shipping from outside the UK.

 

[BMWTurboDzl]

Please forgive me.

Np. Auto correct is a pain. I obviously missed it.

 

[LordNilesStandish]

I just searched for this and it does not seem to be widely available. There were some obscure places that seem to sell it, but it may be shipping from outside the UK.

I think they dropped the 'Supercar' branding, reportedly PAO based.
https://www.castrol.com/en_gb/unite...l-edge-oils/castrol-edge.html#tab_0w-40-a3-b4
Barely a 40 though.

 

[Bozman52]

I just wanted to thank everyone who contributed to the thread. I've ended up choosing Ravenol VST 5W-40 this time around. I'll do an oil analysis on whats currently in the car (Ravenol VMP 5W-30) and post it once I have the results.