BMW E30 - Mobil 1 confusion

[michaelsvintage]

Alright, first off I would like to start by apologizing. I'm almost POSITIVE the answer to this question must be in here, but I can't get the search function to work. If you don't feel like reading all this, the question is at the end.

Just for some background...My name is Mike, and I drive a 1987 BMW 325i with around 150kmi. I currently run a vintage race shop with my Dad and occasionally get to race a 1965 Lotus Cortina as a test driver (I have Youtube videos if anyone is interested!) I live in New York and drive my car all year. The car always warms up fully when I drive it. I currently use Mobil 1 15W-50 as per the "Million Mile Challenge," good specs, and good will from my Dad. I started learning about oil yesterday perusing a BMW subforum that discussed different oil choices. I was directed to the "Motor Oil 101" listed on this site and it was a great read. I had no idea how to actually read the numbers on different oils, what they mean, conventional vs. synthetic, etc.

It inspired me to look at the Mobil Oil website and see what they recommended for my car. That is where I started to get confused.

The website suggested I use Mobil 1 0W-40 for my car. From what I read, the 0W is great for cold starting, the oil still has 1000/1100ppm of Phosphorous and Zinc, and it appears to be pretty popular. Is this a good idea for a car like mine however? I'm concerned that the motor's age and mileage, as well as my location, could mean a "thinner" oil (40 weight vs. 50) would be a bad choice under regular operating conditions. Also, is 1000/1100 enough ZDDP for an older motor such as mine? I know the 15W-50 has more, but I've read that older engines need at least 800ppm so both meet the requirement.


I'm sorry I started to ramble, but I wanted to be as complete as possible right off the bat. I hope someone can help me continue learning about how all this works!

 

[Ramblejam]

Hello, and welcome to the forum! You're to be applauded for taking the initiative to learn about all this stuff.

There's really not a universally correct answer here -- you'll find those with your car running anything from Mobil 1 0w-40, Rotella 5w-40, Delo/Delvac/Rotella 15w-40 to even good 'ol 20w-50.

How has your current 15w-50 performed? Any issues? Maintaining proper pressure?

 

[michaelsvintage]

Originally Posted By: Ramblejam
Hello, and welcome to the forum! You're to be applauded for taking the initiative to learn about all this stuff.

There's really not a universally correct answer here -- you'll find those with your car running anything from Mobil 1 0w-40, Rotella 5w-40, Delo/Delvac/Rotella 15w-40 to even good 'ol 20w-50.

How has your current 15w-50 performed? Any issues? Maintaining proper pressure?



The 15W-50 has performed fine, although I suppose I can't comment on pressure aside from it not having any low pressure warnings. No gauge, just the idiot light on the dash. The one thing I have noticed (that could be related to oil, or could be something in the charging system) is when the car is cold, the electrical system appears a bit labored at idle. For example, dash lights will brighten if I slightly raise rpm. This made me wonder if during this recent period of very cold days, the 15W-50 was proving to be just too thick at cold start. The 0W-40 would obviously be better in this case, but I just don't know enough to know if that choice would have negative consequences in the summer, or in an older motor with higher mileage. Thanks for your reply!

 

[tommygunn]

Welcome to BITOG!

What an awesome story you have. Yeah I'd love to see the Cortina!

 

[stumpypete]

I also have an e30, an 86 325e. I would go with the the Mobil 1 0w-40. It specs for newer BMWs and so will back spec for yours. It will flow easier on the cold winter mornings in NY and give your all the high temp summer coverage you'd want.

 

[Ramblejam]

Originally Posted By: michaelsvintage
The 15W-50 has performed fine, although I suppose I can't comment on pressure aside from it not having any low pressure warnings. No gauge, just the idiot light on the dash. The one thing I have noticed (that could be related to oil, or could be something in the charging system) is when the car is cold, the electrical system appears a bit labored at idle. For example, dash lights will brighten if I slightly raise rpm. This made me wonder if during this recent period of very cold days, the 15W-50 was proving to be just too thick at cold start. The 0W-40 would obviously be better in this case, but I just don't know enough to know if that choice would have negative consequences in the summer, or in an older motor with higher mileage. Thanks for your reply!


Oh, I was unaware you were running the car in winter -- Mobil 1 0w-40 would be an excellent choice, offering all the protection you need in summer, while vastly improving cold weather performance. At $25 for 5 quarts from Wal-mart, I'd get it done ASAP.

 

[michaelsvintage]

Great everyone, thanks for the help! Glad to see another E30 fan here, too! I feel much better about changing to the 0W-40 after hearing your opinions. It sounds like my fears about summer wear and use in an older car/motor have been put to rest!

And speaking of the Cortina...here it is!

Here is the link to my Youtube channel: http://www.youtube.com/user/CarGeekSprinter/videos

I have some videos there from the few chances I get to drive. I helped build the car and I've been the guinea pig while we learn how to set up the suspension. I think this coming season will see the car really come to life! By the way, feel free to add any comments or opinions about that car and/or my driving!

 

[JHZR2]

I've run 15w-50 and 10w-40 HM in my E30 318i (M42). Both were fine. Used the 0w-40 long ago and didn't see any difference.

Personally, for E30 cars, I like 5w-40 HDEOs.

 

[Shannow]

Delo400 15W-40 was what I ran in mine...(turns out it was a 325 engine)...with a Ford filter (Ryco Z-9)

 

[djb]

The confusion stems from BMW's "Special Oil" designation.

The M20B25 engine in your e30 was original documented to use regular oil of various weights based on the expected temperature range, or BMW's 'Special Oil'.

'Special Oil' was a specific product available only through the BMW distribution system. It was apparently an early synthetic. BMW stopped providing 'Special Oil', and issued a SI bulletin to their dealers saying that BMW-LL-98 oil could be used in the older engines.

BMW-LL-98 is a specification for approximately a 5W40 synthetic oil with a heavy additive package. It's intended to last for the 15K-18K mile change interval of the 1998 and later engines. It's much better than needed for a 7.5K mile change interval in the M20. BMW-LL-01 tweaks that to about 0W40.

So basically modern oils are so much better that you can use any of them. BMW approves synthetic oil that's 0W40 or 5W40 for any weather, and regular (conventional or synthetic) oil up to 20W50 depending on the temperature. Reading between the lines, you can pretty much use any synthetic oil.

I typically run synthetic 15W50 in my 1987 325is, but not because I believe that it needs it. Lately it has been getting the NAPA synthetic 15W50, since their semi-annual $3.49/qt sale matches my change schedule.

 

[michaelsvintage]

Originally Posted By: djb
The confusion stems from BMW's "Special Oil" designation.

The M20B25 engine in your e30 was original documented to use regular oil of various weights based on the expected temperature range, or BMW's 'Special Oil'.

'Special Oil' was a specific product available only through the BMW distribution system. It was apparently an early synthetic. BMW stopped providing 'Special Oil', and issued a SI bulletin to their dealers saying that BMW-LL-98 oil could be used in the older engines.

BMW-LL-98 is a specification for approximately a 5W40 synthetic oil with a heavy additive package. It's intended to last for the 15K-18K mile change interval of the 1998 and later engines. It's much better than needed for a 7.5K mile change interval in the M20. BMW-LL-01 tweaks that to about 0W40.

So basically modern oils are so much better that you can use any of them. BMW approves synthetic oil that's 0W40 or 5W40 for any weather, and regular (conventional or synthetic) oil up to 20W50 depending on the temperature. Reading between the lines, you can pretty much use any synthetic oil.

I typically run synthetic 15W50 in my 1987 325is, but not because I believe that it needs it. Lately it has been getting the NAPA synthetic 15W50, since their semi-annual $3.49/qt sale matches my change schedule.



Oh, that's very interesting! So that's what the little chart in my owner's manual suggesting different oils for different temperatures is about. (I know that's very outdated information now, by the way) Very informative, thanks!

 

[Wilhelm_D]

Originally Posted By: michaelsvintage
..... I currently use Mobil 1 15W-50 as per the "Million Mile Challenge," good specs, and good will from my Dad. ..... The website suggested I use Mobil 1 0W-40 for my car. From what I read, the 0W is great for cold starting, the oil still has 1000/1100ppm of Phosphorous and Zinc, and it appears to be pretty popular. Is this a good idea for a car like mine however? I'm concerned that the motor's age and mileage, as well as my location, could mean a "thinner" oil (40 weight vs. 50) would be a bad choice under regular operating conditions. Also, is 1000/1100 enough ZDDP for an older motor such as mine? I know the 15W-50 has more, but I've read that older engines need at least 800ppm so both meet the requirement. ....


The Mobil 1 0W-40 should provide better lubrication over a wider range of temperatures than your current motor oil. It's used with good results in many BMWs, Porsches, Mercedes, and other premium vehicles.

The easiest way to see if it works is to try it. Assuming your engine is in good mechanical condition all you should notice is easier starts and a bit more "pep" due to the decrease in friction from the 15W-50.

If oil consumption increases unacceptably, you'll know that the previous oil was masking some engine wear and can move back to the heavier motor oil.

 

[michaelsvintage]

Originally Posted By: Wilhelm_D

The Mobil 1 0W-40 should provide better lubrication over a wider range of temperatures than your current motor oil. It's used with good results in many BMWs, Porsches, Mercedes, and other premium vehicles.

The easiest way to see if it works is to try it. Assuming your engine is in good mechanical condition all you should notice is easier starts and a bit more "pep" due to the decrease in friction from the 15W-50.

If oil consumption increases unacceptably, you'll know that the previous oil was masking some engine wear and can move back to the heavier motor oil.


Thanks! I'm really looking forward to picking everything up and seeing what differences I notice! I wouldn't mind some time above freezing to do it, though...

 

[stchman]

According to the specs I have read, that car calls for 10W-40 oil. You can safely use either 10W-40, 5W-40, or 0W-40 oil as it's all 40W at operating temperature.

Walmart sells 5qt just of Mobil 1 5W-40 for a reasonable price.

 

[michaelsvintage]

Originally Posted By: stchman
According to the specs I have read, that car calls for 10W-40 oil. You can safely use either 10W-40, 5W-40, or 0W-40 oil as it's all 40W at operating temperature.

Walmart sells 5qt just of Mobil 1 5W-40 for a reasonable price.


Thank you! I decided to go for the 0W-40 due to the increased ZDDP. I did get it at Walmart though!

 

[michaelsvintage]

Changed the oil with the 0W-40 today! I realize any valvetrain noise difference will probably become more apparent in the summer, but it seems pretty much the same now up to 5k. Oil pressure came right up, startup is hard to say since the car was still pretty warm, but I'm most impressed by the difference in resistance on overrun. Letting off the throttle in fourth gear now feels like it used to in fifth. I may just be riding the high of trying something new however, so I will report back in a while!

 

[fdcg27]

My four cylinder e36 is very happy with Maxlife 10W-40.
I suspect that your six cylinder e30 would be as well.
I have run M1 15W-50 in mine and it was fine for warm weather.
I don't think I'd use it as a winter oil, though.
Unless you have really low leaks and consumption and also want to extend drains, I don't think you need to use M1 0W-40.
An overhead cam engine like the one in your car also doesn't really need a high ZDDP oil, since the valve spring pressures are not all that high, unlike those found in an old high performance pushrod engine.
Incidentally, a Lotus 'tina is awesome.
I've seen them in vintage events but have never had the luck to drive one.

 

[michaelsvintage]

Just over 500 miles now and only good news! Cold starts are amazingly easy; it's like it was 70 degrees out instead of 7. Very impressive. Not a noticeable increase in valvetrain noise thus far, no oil pressure problems, no oil comsumption yet (which just means it hasn't gotten worse), and the differences I noticed in my first test drive (lower resistance when coasting in gear, maaaaybe a bit more free-spinning motor) still hold true.

 

[TrevorS]

Good choice with the M1. Pennzoil Ultra 5w40 also meets your specs and for me has different characteristics to the M1. There's also Castrol Edge 0w40. Again it meets your spec and you may prefer it. You should get the same cold start performance from any of these oils.

For a couple of people, I changed out 15w40 to 5w30 on older vehicles and they noticed similar improvements as you have. The manufacturers allowed the lower grade.

 

[michaelsvintage]

Originally Posted By: TrevorS
Good choice with the M1. Pennzoil Ultra 5w40 also meets your specs and for me has different characteristics to the M1. There's also Castrol Edge 0w40. Again it meets your spec and you may prefer it. You should get the same cold start performance from any of these oils.

For a couple of people, I changed out 15w40 to 5w30 on older vehicles and they noticed similar improvements as you have. The manufacturers allowed the lower grade.


I'll obviously be sticking with the M1 for now, but which "different characteristics" would you expect and why might I prefer Castrol or Pennzoil?