How trustworthy are the OEM oil temp & coolant gauges?

[ridebikes]

How trustworthy are the OEM oil temp & coolant gauges?

I was at the track yesterday, and saw the oil temp gauge pegged just beyond the "dot" between 210 and 300.

Is this safe?

[bmwfnatic]

If you are running 10w60, yea, perfectly fine.


This is what the owner's manual says about it. :P

[Estoril]

You can read the specific coolant/engine temperature on OBC display 7.0. I do that when on track in the summer, although I never am anywhere near an issue.

[ridebikes]

You can read the specific coolant/engine temperature on OBC display 7.0. I do that when on track in the summer, although I never am anywhere near an issue.

I didn't realize this was even a thing we could do, thanks for cluing me into this.

Do these instructions look about right for how to enable? https://forums.m3cutters.co.uk/threa...vice-mode.558/

It looks like non-M E46s are slightly different 🤷♂️

[enjoy_m3]

that's kind of a hassle. Just buy a 10 dollar obd bluetooth reader, download torque app, and you can read the water temp in realtime. I wish it also did it with oil temp but it's connected to the oil lever sensor so you'll need to wire up a sensor separately. But to answer your oil temp question, yes it can get up to the 3/4 dot on track days but you really don't want the oil to get that hot. An oil cooler, oil diverter valve and proper ducting will help. In my experience, running redline oil was lower in the temp gauge than motul and liqui moly.

[Obioban]

The non M gauges have a pretty large buffer in the middle. The M3 gauges are pretty accurate as stock, barely any buffer-- I wouldn't bother coding on the digital display.

And that oil temp is slightly higher than normal but fine for tracking on a hot day. I hope you're still on 10w60. If you haven't refreshed your cooling system with new stock, it might be time to start thinking about it (including the oil cooler), but that current situation isn't alarming.

[heinzboehmer]

3/4 dot (255ish) isn't crazy hot for oil on track. Those dots on the gauges are supposed to represent the operating temp under normal circumstances, so 3/4 on the gauge is still fine for the street according to BMW, let alone the track. Like the manual says in that pic above, TWS is supposed to be good up to 300 F.

Those oil temps sound about right for a hotish track day. Now, if this was on a cooler day (say, less than 60 F), I would be looking at the oil cooler to make sure it's doing its job correctly. Mostly checking to make sure there's no debris between the fins and that the thermostat is opening up fully when up to temp.

To answer your original question, the gauge is fairly accurate. Info might have been lost with M3Forum, as I can't find the thread I'm thinking of, but I do remember there being a discussion about how "buffered" the gauges on these cars were. Conclusion was that on non-Ms, there is a pretty big buffer, but that buffer is small/non-existent on the M3s.

[jet_dogg]

How many miles on your rad and oil cooler?

[Jimbo's M]

How trustworthy are the OEM oil temp & coolant gauges?

I'm in Tucson and see this temp fairly often in the summer when we get into the ambient 105F+ range, just like it is now. It's never while driving (I don't track, but have no qualms with 8K either), but after parking the car to run an errand and then coming back out to it. Soon as I start driving, it drops back down to the 230-ish range. Been okay that way for twenty summers.

[ridebikes]

How many miles on your rad and oil cooler?

I did a full OEM refresh of rad & oil cooler (+ Water pump, Tstat, expansion tank & hoses) around 12K miles ago. All BMW, no aftermarket.

I hope you're still on 10w60.

Yup, Liqui Moly 10w60

Just buy a 10 dollar obd bluetooth reader,

Not ideal for a quick glance at speed on track

Thanks everyone for the quick responses. Sounds like not much to worry about.

[Estoril]

that's kind of a hassle. Just buy a 10 dollar obd bluetooth reader, download torque app, and you can read the water temp in realtime. I wish it also did it with oil temp but it's connected to the oil lever sensor so you'll need to wire up a sensor separately. But to answer your oil temp question, yes it can get up to the 3/4 dot on track days but you really don't want the oil to get that hot. An oil cooler, oil diverter valve and proper ducting will help. In my experience, running redline oil was lower in the temp gauge than motul and liqui moly.

What is he going to display the temp on? Very few people have a hard mount for their phone.

[Obioban]

I did a full OEM refresh of rad & oil cooler (+ Water pump, Tstat, expansion tank & hoses) around 12K miles ago. All BMW, no aftermarket.



Yup, Liqui Moly 10w60



Not ideal for a quick glance at speed on track

Thanks everyone for the quick responses. Sounds like not much to worry about.

I bet if you move to TWS, you’ll be on the dot instead of past it.

[jet_dogg]

I did a full OEM refresh of rad & oil cooler (+ Water pump, Tstat, expansion tank & hoses) around 12K miles ago. All BMW, no aftermarket.



Yup, Liqui Moly 10w60



Not ideal for a quick glance at speed on track

Thanks everyone for the quick responses. Sounds like not much to worry about.

At this point the only possible culprit is the oil.

[Jimbo's M]

When I switched indy's to work on my car five years back, they used 10-60 Moly for M cars. I told them I'll stick with TWS, and that's because of this forum, and it's informed opinions over the many years. Not saying Moly sucks, I'm just sayin'. Take that for what it's worth.

[ridebikes]

Thanks guys, sounds like TWS is in the future.

Just to keep the conversation going, I did see this article on motoiq on this very topic, and the author sounded the alarm bells on 260-270 degree temps. It's clear from this forum's wisdom this guy is wrong, correct?

I was seeing 260-270*F oil temps on track, sometimes halfway through a 20 minute session. Luckily, the water cooling system seems to be overbuilt, and I never see over about 195*F water temp. However, once oil temps crept up past about 260F, oil pressure really started to suffer as a result. I’d see 5-10 psi less for a given RPM, quite suddenly, and this was enough to force me to pull off track early or at least do a full cooldown lap.

Who knows, it may be thinly veiled sponsored content by CSF