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I googled but everytime someone asked engine oil temps people started talking about coolant temps. I'm curious what the engine oil temp should be at operating temp? After a short drive and standing idle I'm sitting at 159.8 degrees.
My engine coolant temp is 129.2... it's about 60 degrees out this morning. Thanks
Once my engine is fully warmed up ECT is around 187 to 192 degF and EOT around 190 to 198 degF. Driving at highway speeds 75+ mph for a long time EOT 194 to 200 degF depending on ambient temps and under hard throttle. At idle my EOT is usually within 1 to 4 degrees above ECT. Your temps are very low unless you haven't allowed the truck to get to full operating temperature. Maybe your thermostat is stuck open? It doesn't take long to get above 150 deg for either EOT or ECT at 60 deg ambient temps. Maybe 5 to 6 minutes according to one of my datalogs.But you said it was a short drive. How short? And at what speeds? Drive for 20 minutes and you should be around 190 degF for both EOT and ECT give or take 10 deg. I've not seen 30 deg difference between the two although my ECT often leads EOT while warming up to operating temps, after which EOT takes the lead.
Are you still referencing an '05 6.0L F-250? If so, is it still completely stock or have you made mods?
The reason why you keep seeing references to coolant temps is because the two are tied together via the engine oil cooler. With a healthy stock system, you should be seeing engine oil temperatures no more than 15*F greater than engine coolant temperatures at normal operating temperatures when doing approx 70 mph down the highway. Engine coolant acts as the cooling agent for engine oil via the engine oil cooler.
With a correctly functioning coolant thermostat, you should be seeing approx. 188-192*F engine coolant temperature (ECT) and approximately 190-207*F engine oil temperature (EOT).
Are you still referencing an '05 6.0L F-250? If so, is it still completely stock or have you made mods?
The reason why you keep seeing references to coolant temps is because the two are tied together via the engine oil cooler. With a healthy stock system, you should be seeing engine oil temperatures no more than 15*F greater than engine coolant temperatures at normal operating temperatures when doing approx 70 mph down the highway. Engine coolant acts as the cooling agent for engine oil via the engine oil cooler.
With a correctly functioning coolant thermostat, you should be seeing approx. 188-192*F engine coolant temperature (ECT) and approximately 190-207*F engine oil temperature (EOT).
What are you using to measure your temperatures?
**** I always forget to say what I drive lmao. 05 f250 all stock
What is coolant temp after a healthy run?
129 for coolant is way low. Thermostats are a known failure/maintenance item.
Oil temp tracks coolant, and should be slightly higher, at idle, maybe 5 degrees, towing, working, no more than 20.
Oil cools turbo, sheds heat into cooling system.
It's been difficult the past few days. It's about 40degress out and getting this truck to temp even when smashing is difficult. I tried again today and was only able to reach about 150 degrees coolant temp. Oil temp was 194 when I gave up. Not sure if the outside temp is making it run cold or if I'm just not driving it enough or if something els is going on.
Normally the oil temp lags behind the coolant temp until the coolant temp stabilizes. If your readings are accurate, then you have a plugged oil cooler IMO.
Normally the oil temp lags behind the coolant temp until the coolant temp stabilizes. If your readings are accurate, then you have a plugged oil cooler IMO.
Damn, is there a way to verify if it's plugged or going bad? It drives fine.
I am unsure, the truck was bought and sold a few times so no one knew the history. It's something I just started noticing because I finally got some injectors replaced and actually been able to drive the truck around. I noticed the temp gauge doesn't move at all really and that's when I started monitoring the temps.
If your temperature sensors are accurate, the way to condemn an oil cooler is to get the engine fully up to operating temperature (coolant at 190*F +/-) and with the oil temperature stabilized. If the oil is more than 15 degrees hotter than the coolant (most forum people stipulate to be driving at a constant 65 mph for this test), then your oil cooler is plugged.
Every time I have seen the oil temperature exceed the coolant temperature BEFORE the coolant has fully warmed up, the oil cooler has been plugged. You certainly may have a thermostat issue, but if your coolant is cool, then so should be the oil - IF your oil cooler is working.
There is one exception folks have discovered. That exception is if the oil cooler bypass valve has stuck open. The only way I know of to test this is to change that bypass valve out, and hope your system returns to normal. Maybe others have a better suggestion.
If your temperature sensors are accurate, the way to condemn an oil cooler is to get the engine fully up to operating temperature (coolant at 190*F +/-) and with the oil temperature stabilized. If the oil is more than 15 degrees hotter than the coolant (most forum people stipulate to be driving at a constant 65 mph for this test), then your oil cooler is plugged.
Every time I have seen the oil temperature exceed the coolant temperature BEFORE the coolant has fully warmed up, the oil cooler has been plugged. You certainly may have a thermostat issue, but if your coolant is cool, then so should be the oil - IF your oil cooler is working.
There is one exception folks have discovered. That exception is if the oil cooler bypass valve has stuck open. The only way I know of to test this is to change that out and hope your system returns to normal. Maybe others have a better suggestion.
Under normal driving conditions, about how long do you think it would take for it to get to normal temps?
It takes me every bit of 15 minutes. That includes highway driving.
Ok. I'll give it another go wth the scanner.
Is there a way I can see if someone's replaced the oil cooler before? While trying to find a oil leak I found a part number and a "China" stamp on the egr cooler so I looked that up and found it to be a doorman egr cooler. So I know that's been replaced before. What are the chances they did the oil cooler?
01-11-2019, 11:07 AM
