Z4M oil: Castrol or original BMW? Quick reply appreciated

[bananabun]

Family owns a business manufacturing engine oils for extremely heavy duty use such as 4,000 hp mining trucks. Yes, 4,000 hp. We also had OEM contracts for Mercedes and Volvo in some Asian countries.

It all comes down to the base oils and additives used in the blending process. You want a well-proven mix of PAO's and Group 3 oil that can withstand the repeated viscosity change from high temp application. Some people like to chase the 'true synthetic' standard, which is PAO's only, but it's a little overkill and doesn't make good business sense for manufacturers anyway. Manufacturers will never reveal the actual blends, but if you're in the industry then you can read between the lines in a product data sheet.

I only use Liqui Moly, and I send oil samples to Blackstone and to my 'friends' at the factory. Very, very pleased with results so far and I don't think there's any reason to shop around.

[garz747]

I stick to the old OEM castrol 10w60. Order the E46 M3 package from GETbmwparts and thats what you can get. I read the most exhaustive oil analysis research paper ive ever seen and penzzoil ultra 5w30 was rated the highest out of every oil sold in the USA. Wrong viscosity- so im happy with the castrol. The bmw turbo 10w60 is made from natural gas as well and those oils have not been rated as high.

[SaltyNC]

I ordered BMW Twin Power Turbo 5W-30 for my Z4MR...when I wasn't paying close enough attention on the website and decided I wanted a couple extra liters to go with my 10W60 oil change kit. Luckily, I have a MINI, so it won't go to waste.

Salty

[The HACK]

Originally Posted by garz747

I stick to the old OEM castrol 10w60. Order the E46 M3 package from GETbmwparts and thats what you can get.

Not anymore. Last time I ordered they sent the Shell TwinTurbo 10w-60.

[Ryan13]

I'll chime in for a few thoughts. As someone whose already blown one S54, perhaps a little firsthand experience.

When I purchased the coupe, it had 80k on the engine. Bearings had not been touched and I can't speak for all the previous maintenance. Valve cover gasket had a small leak at the back, I took the car to RRT and had them go over it completely and do any and all maintenance or repairs. I pulled the oil and sent to Blackstone. Report came back normal...presume it had 10w60 per the previous owner records.

Since the car was going straight to track duty, RRT wanted me to run Motul 300v 15w-50. I've been around these cars-engines a long time and have 2 others sitting in the garage (Z3MR and Z4MR). Without going into the excruciating details which has been hashed since the first and second gen bearings on 2001-2002 S54 engines, i was hesitant to run the an oil different than the BMW recommended 10w60. But I went with RRT suggestion and made the change...just for the coupe.

Tracked it hard for around 12 track days in the summer of 2016. Or rather in Hack's terms, around 60 x 20 minute sessions and a around 4 x 2 hour sessions (TrackDaze opens the track at 3:30 a 5:30...I wanted to see if I could do the entire session on track, sans a fuel stop).

Pulled the oil in late August for blackstone. Report back was oil was fine (probably 2000 miles to be fair), no wear indicators, could go another 2000 miles no issue. Here is where I think I made the mistake. I had purchased 6 LubeMoly kits from ECS...3 cars, 2 changes each. So, I used one of the LubeMoly 10w60 kits. 8 normal track days later (call it 25 or so 20 minute sessions), coming around a turn, I felt a slight release of power...like about half the power just went away.

You can check the other threads for details if you like, but moral of the story, I only run Motul now in all my cars...street or track. It's a double ester oil, I warm up the engines (below 3000 rims for 15-20 minutes) and my reports are all clear.

All that said, the bearings are a maintenance item, just change them every 60k miles and call it a day. Do the Vanos bolts and put in a cast Vanos hub (tabs break on the OEM), and I'm pretty certain you can beat these engines as hard as you want.

[SaltyNC]

Originally Posted by Ryan13

I only run Motul now in all my cars...street or track. It's a double ester oil, I warm up the engines (below 3000 rims for 15-20 minutes) and my reports are all clear.

Ryan, are you using Motul 10W60 for street?

Salty

[Ryan13]

Hi Salty. No, I'm using the 15w50 all the way around. I let the car warm up, but I also keep the cars indoors so rarely below 50 degrees ambient temperature. Even when it is cold outside, the car never sits long enough to cool down significantly, so I don't worry that 15w will be too thick.

At the track, I let the car warm up for 10 minutes before each session, no matter the temperature outside. Then one " medium" lap to get the everything up to temp.

I would use the Motul ester 10w60 as well. It's the ester oils in group 5 base that I'm sticking with more than any specific weight or brand. I get all the arguments about staying with the BMW recommendations, but the base stock and the breakdown of the oil is, at least to me, more important. RRT is a pure race shop with a service bay for us common folk. They made me a believer. But I wouldn't do coated bearings either, theoretically less space between bearing and crank (Randy Forbes is big on the Z3 boards) and I probably wouldn't run 0w or 5w.

All the info I've come across and talking to people like Randy, Thayer, and Lang is that the only way you can really "fix" the problem is to grind the journals down, put in wider shells, and magnaflux the crank to straighten it. I know this discussion is about oil and I don't mean to dredge up rod bearings...but in our world, oil and rod bearings can't really be separated. Flow at startup is really far down the list for me since I do a good warmup. BMW decided we needed a thick molecule to absorb/cushion the crank's rotation, rather than fixing the problem. They tried a different bearing in late 2001 for a few months, but went back to the original (or at least original specs) and changed the oil. M3 guys got a recall, Z3 guys got nothing.

[SaltyNC]

Ryan,

There was an interesting discussion some time back about laser treating the surface of the bearings. Basically, the idea was to create many millions of micro nooks and crannies for the oil to sit in. The WPC treatment is similar, but different and probably superior due to other benefits from micro peening. At least with WPC and laser surfacing, there wouldn't be any additional thickness. I'm going for the WPC treated bearings when the time comes very soon.

And I agree, the main reason we talk about oil around here is looking for correlation/causation for bearing wear and engine failures. :-)

Good info on micro peening and WPC:
http://www.superstreetonline.com/how...wpc-treatment/

Salty

[StickMon]

So sticking with 10W-60, it seems we're left with:
1a) Castrol (Edge TWS - Limited supply left)
1b) Castrol (Edge Supercar - as used in Koenigseggeggeggeggegg
2) BMW TwinPower Turbo (Shell)
3) Liqui-Moly
4) Red Line
5) Motul 7100 4T

[yousefnjr]

Originally Posted by StickMon

Thanks. I didn't know there was a "Castrol Edge Supercar".
Could be a contender for my next change, especially if our filters are on Amazon.

https://www.amazon.com/gp/aw/d/B0080...p_2_2?pi=SS115

[yousefnjr]

Originally Posted by SaltyNC

... micro peen ...

Sorry I’m 11 years old

[StickMon]

Originally Posted by yousefnjr

https://www.amazon.com/gp/aw/d/B0080...p_2_2?pi=SS115

Thanks!
Figured they were. I was just too busy (or lazy) to look.

[ZAR4MC]

Originally Posted by bananabun

Family owns a business manufacturing engine oils for extremely heavy duty use such as 4,000 hp mining trucks. Yes, 4,000 hp. We also had OEM contracts for Mercedes and Volvo in some Asian countries.

It all comes down to the base oils and additives used in the blending process. You want a well-proven mix of PAO's and Group 3 oil that can withstand the repeated viscosity change from high temp application. Some people like to chase the 'true synthetic' standard, which is PAO's only, but it's a little overkill and doesn't make good business sense for manufacturers anyway. Manufacturers will never reveal the actual blends, but if you're in the industry then you can read between the lines in a product data sheet.

I only use Liqui Moly, and I send oil samples to Blackstone and to my 'friends' at the factory. Very, very pleased with results so far and I don't think there's any reason to shop around.

+1 for the LiquiMoly Racetech... our S54's seems happy with it...

[Ryan13]

I would probably do the WPC bearings as well just for the theory that the micropores would help retain oil film. I don't know that hardening the material would create any value in a sacrificial part like the bearing...after all, we want wear at/on the shell vs wear on the crank. For the benefit of reduced friction, hopefully there won't be any friction to reduce, it the two parts are touching, that's when there would be friction, and if there is friction, got a bigger problem.

I need to correct one statement...the bearings were changed in October 2001 - February 2002. Lot of failures in that range.

If the mods allow posting of links to other sites, then enjoy.

Oil
http://www.m3forum.net/m3forum/showthread.php?t=295656

Bearings
http://members.roadfly.com/jason/m3engines.htm

[SaltyNC]

This is getting off the original thread, but this is an interesting discussion of bearings. A good number of S65 and S85 guys are using BE bearings that have greater clearance and a coating. Field data is still not plentiful. BE Bearings makes a set for the S54, as well. I had found these a couple of months back when my lead levels spiked on my oil analysis. I'm still considering the BE bearings as an alternative to the WPC treated bearings.

http://www.hotrod.com/articles/selec...gine-bearings/

https://www.bebearings.com/Overview.html

Salty

[elerner61]

After considering how I use my car (All year round, Northeast Winter time cold starts that are often below freezing, no autocrossing/track use but spirited drives) I think I'm going to stay with the Castrol. The inferior cold start characteristics of the Liqui Moly is the deciding factor for me.

[Andyh1]

Considering I'm in Houston and my Z4M is a weekend car only (no tracking).
I've stuck with Liqui Molly 10w60 plus I add a can of lubro Molly MoS2.
I run this oil combo on my wife's E70 X5 and my mom's E53 X5.
Engines running much smoother.
I'll run my first oil analysis at the end of the year on the Z4M to see where I am.
Mileage is 28K

[Finnegan]

Originally Posted by yousefnjr

[IMG]http://replygif.net/i/593.gif[/IMG]

Sorry IÂ’m 11 years old

Dude, lol!!!!


And generally, great discussion! I too run the 15-50 oil. I live in a relatively warm area, and follow all of the same procedure as discussed above.