[allstar335is]

Hey guys iv got a 335is and my oil temp gets up to normal operating temperature 110c after about half an hour of highway driving but the issue that’s coming up is when I keep driving after that half hour and into 45mins-1hour my oil temperature will start to drop to 90c and even down to 80 iv notices. Any ideas why this might occur. Recently topped off my coolant reservoir with distilled water but no difference . Thanks

[Pladi]

chances that your temperature inside a running engine is fluctuating so fast after already reaching operating temp and driven on a highway is next to ZERO. If it went up then thats another story. So i think your sensor is not good. Thats my guess with limited information.

[allstar335is]

Originally Posted by Pladi

chances that your temperature inside a running engine is fluctuating so fast after already reaching operating temp and driven on a highway is next to ZERO. If it went up then thats another story. So i think your sensor is not good. Thats my guess with limited information.

I assume your talking about the oil temperature sensor ?

[RomKaN54]

you have 335is which means you have dual oil cooler radiators with a thermostat. with highway cruising speeds and Toronto temps im not surprised. I live in Phoenix I drop 10 degrees if i cruise highway speed for a while.

[allstar335is]

Originally Posted by romka2087

you have 335is which means you have dual oil cooler radiators with a thermostat. with highway cruising speeds and Toronto temps im not surprised. I live in Phoenix I drop 10 degrees if i cruise highway speed for a while.

So you think if I constantly push the car the oil temp will stay the same? Previously I could drive it for a couple hours and the oil temp gauge wouldn’t move. It’s odd to go from 120c and drop to 90c but if the dual radiators are working with the thermostat in this weather that makes sense.

[Phyrexia]

Seems like normal operating behavior.

I had similar experiences in my M3 (which just has one oil cooler and no oil thermostat to my knowledge). Seems normal.

How cold is it up there? At -5C ambient I'd see a marked decrease in "operating" oil temperatures, especially at higher speeds, like 90mph/150kmh and up.

[allstar335is]

Originally Posted by Phyrexia

Seems like normal operating behavior.

I had similar experiences in my M3 (which just has one oil cooler and no oil thermostat to my knowledge). Seems normal.

How cold is it up there? At -5C ambient I'd see a marked decrease in "operating" oil temperatures, especially at higher speeds, like 90mph/150kmh and up.

It’s about -5 I guess at highway speeds it could be much colder... might have to wait on a warmer day to see how the temperature fluctuates

[Phyrexia]

You might consider changing to a different oil? I'm not well versed on the N54 though.

[allstar335is]

Originally Posted by Phyrexia

You might consider changing to a different oil? I'm not well versed on the N54 though.

Just used castrol 5w40 ll-01 a week ago.. was following bmw’s long change intervals but finally said fuck it because I saw some other posts in regards to sludge build up over time and carbon as well so I’m going to be changing more frequent every 10k opposed to their 20k intervals

[Pladi]

Originally Posted by allstar335is

Just used castrol 5w40 ll-01 a week ago.. was following bmw’s long change intervals but finally said fuck it because I saw some other posts in regards to sludge build up over time and carbon as well so I’m going to be changing more frequent every 10k opposed to their 20k intervals

what 5w-40 castrol is LL-01 in GTA ? you mean 0w-40 ?

Even if you are sure its 5w-40 why would you use that when 0w-40 is available everywhere..

[Phyrexia]

Originally Posted by allstar335is

Hey guys iv got a 335is and my oil temp gets up to normal operating temperature 110c after about half an hour of highway driving but the issue that’s coming up is when I keep driving after that half hour and into 45mins-1hour my oil temperature will start to drop to 90c and even down to 80 iv notices. Any ideas why this might occur. Recently topped off my coolant reservoir with distilled water but no difference . Thanks

Something else you may consider of that you should (especially in your part of the world, in this part of the year) be running 50/50 coolant/water. You added 100% distilled water. Water cools a motor more effectively than coolant, so you could be experiencing lower coolant temps than normal, which could be contributing to lower oil temps.

I'm not sure if moving to 0w40 would help since you're already at operating temperate when this happens... But again I'm not an N54 guy. You've got those turbos to keep happy.

[allstar335is]

Originally Posted by Pladi

what 5w-40 castrol is LL-01 in GTA ? you mean 0w-40 ?

Even if you are sure its 5w-40 why would you use that when 0w-40 is available everywhere..

Yea there is castrol 5w-40 ll-01 in the gta.. check your local Canadian tire .. the 0w-40 is also ll-01but European formula, the 5w-40 isn’t European formula, what’s the benifit of the 0w40 European formula ?

[Pladi]

Originally Posted by allstar335is

Yea there is castrol 5w-40 ll-01 in the gta.. check your local Canadian tire .. the 0w-40 is also ll-01but European formula, the 5w-40 isn’t European formula, what’s the benifit of the 0w40 European formula ?

non European formula is NOT LL-01...

European forumulas are 0w-30 and 0w-40

5W-40 is not approved for BMW. Not the one you buy in Canada.

Even if it was in canada with -20 degrees temp i would put 0W only because all the wear happens during cold start. You want oil to flow quickly. 5w-40 does not really do as good of a job as 0w-40

W stands for winter. the lower the number the "thinner" the oil is at cold operating temp..

[allstar335is]

Originally Posted by Pladi

non European formula is NOT LL-01...

European forumulas are 0w-30 and 0w-40

5W-40 is not approved for BMW. Not the one you buy in Canada.

Even if it was in canada with -20 degrees temp i would put 0W only because all the wear happens during cold start. You want oil to flow quickly. 5w-40 does not really do as good of a job as 0w-40

W stands for winter. the lower the number the "thinner" the oil is at cold operating temp..

I just check the castrol website. Yes it is approved LL-01
Here’s a link, check it out.. there are multiple products from castrol that are 5w-40 so pick the right one

https://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/E13A9F271142244680257FAA0072394D/$File/BPXE-AA5D4U.pdf

.. 0 is thinner for the winter but 5w suits me just fine and it works amazing so far since spring is around the corner, might consider 0w come next winter

[feuer]

Originally Posted by romka2087

you have 335is which means you have dual oil cooler radiators with a thermostat.

What?

[Phyrexia]

Originally Posted by feuer

What?

Which part do you fail to understand? 335is cars have N54s with two air->fluid radiator style oil coolers, one on either side of the car, with an oil thermostat to regulate the flow through said coolers.

[feuer]

Originally Posted by Phyrexia

Which part do you fail to understand? 335is cars have N54s with two air->fluid radiator style oil coolers, one on either side of the car, with an oil thermostat to regulate the flow through said coolers.

That would be incorrect. There is AUX coolant radiator on the left and oil radiator on the right. There aren't two oil radiators period.

[Phyrexia]

Ah indeed. As I said (third time now) I'm not well versed in N54s. I did think there was an oil cooler on either side, though.

Doesn't seem relevant to the discussion either way. Two oil coolers or one, driving at highway speeds in -5C is going to decrease oil temp.

[feuer]

Originally Posted by Phyrexia

Doesn't seem relevant to the discussion either way. Two oil coolers or one, driving at highway speeds in -5C is going to decrease oil temp.

I have the above discussed radiator setup and drive this car during -20c and oil temperature doesn't drop or fluctuate. I have posted photos in another thread
from my gauges. Is possible that the car is acting up. Eventually problem will become more obvious but usually failing thermostats do this.

[allstar335is]

Originally Posted by feuer

I have the above discussed radiator setup and drive this car during -20c and oil temperature doesn't drop or fluctuate. I have posted photos in another thread
from my gauges. Is possible that the car is acting up. Eventually problem will become more obvious but usually failing thermostats do this.

So you have a link in regards to the thread you have mentioned above, I notice in past winter driving conditions that the car would maintain normal oil temperature and not drop so it was odd when I noticed that the oil temperatures were fluctuating. Thanks for the input

[feuer]

Originally Posted by allstar335is

So you have a link in regards to the thread you have mentioned above, I notice in past winter driving conditions that the car would maintain normal oil temperature and not drop so it was odd when I noticed that the oil temperatures were fluctuating. Thanks for the input

Here you will find some photos:
http://www.e90post.com/forums/showth...3#post22723453
http://www.e90post.com/forums/showth...828362&page=54
-20c oil was 90-95. -10c oil was 100.

[allstar335is]

[QUOTE=feuer;22887514]Here you will find some photos:
http://www.e90post.com/forums/showth...3#post22723453
http://www.e90post.com/forums/showth...828362&page=54
-20c oil was 90-95. -10c oil was 100

If the thermostat is in the progress of failing do you think there might be a code in regards to it failing? Does it completely fail when it stays open or closed?