[redwildcat17]

Looking to buy an fcp euro oil change kit, but torn as to weather to do the 5w-30 or 5w-40 luqi moly. I think I want to stick to the oem 5w-30 but have heard of lots of people running 5w-40, what would be the benefits of it?

Thanks for any advice

[Ozzie335i]

When I went with Liqui Moly 5w-30 last year I felt an immediate difference coming from the OEM stuff. Dare I say the engine felt slipperier. A weird way to put it, but I know my ride, and that is the best way I can describe it. Much smoother. I live in Texas. I have an oil cooler with a cheater thermostat. Cruising for several miles at 85 + mph with it 100 degrees out today the oil temp was 215. I see no need for 5w-40. Now if that Blackstone comes back clean I'll be one happy camper.

[redwildcat17]

Originally Posted by Ozzie335i

When I went with Liqui Moly 5w-30 last year I felt an immediate difference coming from the OEM stuff. Dare I say the engine felt slipperier. A weird way to put it, but I know my ride, and that is the best way I can describe it. Much smoother. I live in Texas. I have an oil cooler with a cheater thermostat. Cruising for several miles at 85 + mph with it 100 degrees out today the oil temp was 215. I see no need for 5w-40. Now if that Blackstone comes back clean I'll be one happy camper.

I think that's what I'm leaning towards. I don't have an aftermarket oil cooler so my temps generally sit around 240ish when fully warm, would 5w-40 keep the temps lower or what would be the advantage?

[Ozzie335i]

I cant definitively answer the temp question. But with the exact same hardware my engine felt smoother when I went from OEM to the Liqui Moly. Does smoother equate to less drag / wear / temp? For my money, yes. As the FCP deal is as cheap as it gets, is it worth it for you to give it a try? Only you can say. Give consideration to one of those drain plugs with a magnet in it. Other than a few minor metallic particles mine came up clean the other day. Was reassuring.

[Welcome to NBA Jam]

The only difference I've found with 5w40 is a significant decrease in oil consumption. I have not measured any other changes.

I have seen tuning companies recommend using 5w40 with tuned turbocharged engines. I do not know the exact reason for this.

[Will_460cs]

Hi,

It simply the viscosity at a given heat range. so 5w-40 allows for more extremes. To learn more I'd recommend looking at Bob the oil guy link below. Generally speaking a 5w-40 is more expensive oil than a 5w-30 as it has to not thin out at the higher end of the temp. ranges.

Personally I run 5w-40 in both my N53 and N55..

As a 5W-40 is a little thicker it won't slip past the valve seals and rings, it will also be a little better at higher temps.

https://www.bobistheoilguy.com/viscosity-charts/

[lwgrenier]

This has been discussed quite a bit on the rod knock tracking thread. Start from the bottom of page 2... might help you make a decision:

https://www.e90post.com/forums/showt...1513898&page=2

[redwildcat17]

Originally Posted by lwgrenier

This has been discussed quite a bit on the rod knock tracking thread. Start from the bottom of page 2... might help you make a decision:

https://www.e90post.com/forums/showt...898&page=2

Very helpful info. Pushed me in the direction of 5w-30 with all the info on the tight clearances and what not. Thanks!

[Will_460cs]

Not sure why that thread would push anyone to either of the 2 oil choices...



If you wan't to know whats going on with your engine, you need to do regular Oil Analysis, that is the only way to monitor metals, fluid and contaminants present in the oil. One of posters on that link that had an engine blow that had a recorded high iron content, iron content is crankshaft wear, so no surprise that the engine then spun bearing...

When you start pushing on an engine get the oil analysis done regularly and use the information.... Bearing don't last for ever and N class engines can and do suffer from surge problems when tracked, allot more for than S class engines..

[redwildcat17]

Originally Posted by Will_460cs

Not sure why that thread would push anyone to either of the 2 oil choices, but each to their own...

Bottom of page 2 starts the talk about oils

[Will_460cs]

yeah I know unread all 5 pages, but its allot conjecture!


Thing is, Kinematic Viscosity is so close on 30 or 40 it makes no difference..

What am I a missing?

[Will_460cs]

If you want to know more, this is excellent:

https://www.bobistheoilguy.com/putti...nto-viscosity/


Here is My view, for what its worth:

Thing is engine failing on track at high Rpm having the nuts crashed off it, are subject to high heat - this is when a thicker oil is better as it will give you a greater level of protection.

However that thicker oil must also provide protection in more normal circumstances. So either a 5w30 or 5w40 would be fine, the latter may provide a bit more protection hence why allot of tuners may opt for it as people who tune their cars are more likely to push them harder..

[redwildcat17]

Originally Posted by Will_460cs

If you want to know more, this is excellent:

https://www.bobistheoilguy.com/putti...nto-viscosity/


Here is My view, for what its worth:

Thing is engine failing on track at high Rpm having the nuts crashed off it, are subject to high heat - this is when a thicker oil is better as it will give you a greater level of protection.

However that thicker oil must also provide protection in more normal circumstances. So either a 5w30 or 5w40 would be fine, the latter may provide a bit more protection hence why allot of tuners may opt for it as people who tune their cars are more likely to push them harder..

So basically the viscosity difference between the two is pretty minimal to the point where it shouldn't affect anything, but the thicker oil does offer increased protection in high heat? So if I'm stage 1+ and plan on going stage 2 or 2+ soon I should go with the more heat resistant oil? Sorry I'm fairly new to the whole tuning/doing my own maintenance thing.

[Will_460cs]

Originally Posted by redwildcat17

So basically the viscosity difference between the two is pretty minimal to the point where it shouldn't affect anything, but the thicker oil does offer increased protection in high heat? So if I'm stage 1+ and plan on going stage 2 or 2+ soon I should go with the more heat resistant oil? Sorry I'm fairly new to the whole tuning/doing my own maintenance thing.

No problem! If you track the car or push it hard and see some higher oil temps then a 5w-40 would be my choice, of course a quality oil is key..

Personally I would also opt for a LL04, some will say it doesn't matter because Long life isn't a requirement, However the spec i.e. LL04 will determine what other things are present in the oil, like Molybdenum, Calcium, Phosphorus, Zinc etc etc.. These are all things that make up the BMW spec... Again personal choice but it not hard to get a LL04.


Above all DO OIL Analysis, read this if you want more info...

https://www.bobistheoilguy.com/engine-oil-analysis/

[lwgrenier]

Obviously the thread was all conjecture. I run 40 weight right now (only LL01 at the store) for my DD and my car is fine. Recently sent a sample to blackstone, we’ll see how it looks. I do think I’ll switch to 30 weight next oil change only because of the tight bearing clearances. I think the majority of the people on this forum don’t track their cars or drive them insanely hard. Given that I’d rather just use 30 weight if, by chance, it could keep the rod bearings better lubricated.

[Rob09msport]

These engines are high shear so most 40s end up 30 pretty quick, long life oils shouldnt matter as any tuned car should be running short oci. Last is thinner oils shed heat quicker but thicker can hold more so take longer to get hot

[Pladi]

in today's oil, shear stability is not dependent on oil weight but the additive package. You can have 30 wight oil with better shear stability if the additives are good.. Long story short 40 weight is not necessarily better oil or offers better protection even at operating temperatures or more heat.. That use to be true.. Car manufactures including BMW are moving towards lower weight because of today's oil technology. Lower weight offers more flow and good protection.

[LiquidREVUP]

I use 5w-40 Motul 8100 x-Cess. Haven't had any issues so far.

[Pladi]

Originally Posted by LiquidREVUP

I use 5w-40 Motul 8100 x-Cess. Haven't had any issues so far.

you have not had any issues so far with an oil that BMW says is ok to use ????? WOW you dont sayy

[LiquidREVUP]

Originally Posted by Pladi

you have not had any issues so far with an oil that BMW says is ok to use ????? WOW you dont sayy

Yep

[Will_460cs]

Originally Posted by Pladi

in today's oil, shear stability is not dependent on oil weight but the additive package. You can have 30 wight oil with better shear stability if the additives are good.. Long story short 40 weight is not necessarily better oil or offers better protection even at operating temperatures or more heat.. That use to be true.. Car manufactures including BMW are moving towards lower weight because of today's oil technology. Lower weight offers more flow and good protection.

Interestingly Also the GF-3 and GF-4 oils have less additives cumulatively and BMW would need to specify the OIL additives outside of GL3 and GL4 in their LLXX specification.

I am aware BMW have reduced the weight in the latest crop of engines but interestingly not for s class engines, I suspected they are not interested in longevity at high stress e.g. hard driving, track etc...

If you want to be informed then by doing regular analysis of the oil you will understand whats happening to the engine in terms of wear (metals) and if there are contaminants e.g. Silica (generally through poor air filtration), Water in the oil (phosphorous I think is the tell, Fuel in the oil (leaky injectors) TDS/Carbon (i.e. longevity of oil) etc...


This is interesting:

After the base oil has sheared or squeezed out, The last line of defense is an additive that puts down a barrier film. This additive usually has higher levels of strength against shearing so it helps keep the wear down. Alright, here’s the catch. In 96, the lubrication industry changed from the SH to SJ API rated oil by reducing the barrier lubricant additives to help preserve cat converters on cars. Why?, It appears that the manufactures / lubrication experts are concerned with contaminating the cat converters with the standard antiwear additives in the motor oils so they have reduced the levels of antiwear additives to preserve the cats. Hmmm, guess what, When they introduced the new SL GF-3 oils, They left it the same. Ok, not out of the woods yet… Now the new GF-4 oils are in the works in hopes to be introduced next year around April. Have a guess one of the things they are going to do?, YEP, reduce the current antiwear additives again.

from this article..


https://www.bobistheoilguy.com/effects-of-shearing/

This is interesting because picking viscosity is in my view the best way to prevent engine damage and the additives are a last line of defense, as such relying on the additives in a track or hard use application is in reality a gamble! Especially as additives have to be defined by the in this case BMW which means you have to get a LLXX spec oil to match... I can see in the future people dumping in 20w oil which doesn't have the right additives and engine wear increasing dramatically, this is exactly what happened with the S54 engine when people didn't run Castrol 10w60 (edge/Motorsport and Supercar), there was allot of premature bearing wear.

Ill be sticking to 5w-40 LL04 as the additives package is to BMW's specification and using OIL Analysis as my "yardstick", I'm picking 40w over 30 because my cars see some heat through driving style and unless I see anything like copper/iron in the oil analysis I know that there isn't any abnormal bearing wear.

[Ozzie335i]

I think I chose properly as I went with 5W30 for flow, as my ride has an afrermarket oil cooler to keep oil temp somewhat low in high temperature conditions. As mentioned the other day: "Cruising for several miles at 85 + mph with it 100 degrees out today the oil temp was 215." I've got the high temperature covered, so higher viscosity is unnecessary. There is a reason that when going from the Stage 2 to Stage 3 Dinan tune a larger oil cooler was required. Could it be that some discussion between BMW and Dinan took place? The big money that I spent on Dinan approved stuff in order to maintain my CPO may now finally be paying off in dividends.

As far as low temperature is concerened, the article that Will connected to mentioned cooling two different oils until one still seeped out in a test. The other came out in globs. Could globs, on a momentary basis, cause lubrication starvation and possibly cause bearing wear that over time could eventually lead to a spun bearing? Even the guys that poo pooed my bringing up that possibility can at least consider it.

Two columns need to be put into the sheet: Do you track your car? And by that I do not mean drag race. And: Do you live up north, where temps may be under 20 degrees F?