The thing you have to remember is the coolant temperature sending unit reads the temps coming out of the motor. The coolant temps coming out of the radiator is going to be quite a bit less than that, and the oil cooler is the first thing to get coolant. It gets the absolute coldest possible coolant.
Oil cooling
- Thread starter super diesel
- Start date
The thing you have to remember is the coolant temperature sending unit reads the temps coming out of the motor. The coolant temps coming out of the radiator is going to be quite a bit less than that, and the oil cooler is the first thing to get coolant. It gets the absolute coldest possible coolant.
I don't have post cooler temps (no gauge sensor there). My vote is "serious doubt that the stock oil cooler/heater is up to snuff when were pulling loads or pushing it past the design specs GM had in mind it for". Why would I think this? Why would they not install a EGT gauge in our trucks as well? There is some proof here that the stock oil cooler/heater is found wanting. The stock oil cooler/heater is trying to maintain a certain temp with the engine oil. At some point the heat exchanger can't keep up. Remember. It only takes once to unknowingly (if you don't have an accurate gauge) start breaking the oil down, and then from that point your constantly driving around unaware that it has been compromised in it's ability to lubricate and protect the motor as well as fresh oil that hasn't been compromised. Your not looking at instant breakdown in most cases, but the wear does become a factor. Just bringing the reality.
Maybe I missed it but I haven't read in this thread (or the other twins related oil cooling threads) about what type of coolant you are all running? Oil viscosity has been discussed briefly but nothing about running a high quality higher heat transfer coolant? Wouldn't running a more performance based coolant work more efficiently keeping temps more reasonable?
You raise a good point and it is exactly the reason I stay away from DexCool. I am running Detroit Power Cool now...no more electrolysis or costly refills:thumb:
So I took my oil cooler off to look inside. The port on the top is direct from the motor, pre filter and pre cooler, seems this is the best place to measure oil temps. I had my oil temp probe in the port in front of the oil filter at a angle towards the driver side tire. This port is after the oil goes through the filter and cooler.
This makes me wonder how hot my oil really was when my gauge was reading 256*. At the time it propmted me to change my oil and send a sample to blackstone.
Here is the UOA.
This makes me wonder how hot my oil really was when my gauge was reading 256*. At the time it propmted me to change my oil and send a sample to blackstone.
Here is the UOA.
Wow this is a real good thread. Michael, I've ran Eisenhower pass numerous times with a 13ft drop in camper, sometimes towing another camper behind it. Something I never would have thought about. There was one time my BOV malfunctioned and I had a huge boost leak running up the west side. This caused the coolant to hit about 240°F by the time I was to the top. Got stopped in traffic after that and noted my oil pressure was almost touching the red tick mark 
I'll definitely have to get a gauge on mine here as soon as taxes get back.
I'll definitely have to get a gauge on mine here as soon as taxes get back.
Here is an article (LONG) Michael, Killerbee, had written about oil cooling, the DMAX, and such..
http://killerbeeperformance.com/download/oil-eoc/OIL COOLING.pdf
Also, a link to the tech data for his kit and pricing.
http://killerbeeperformance.com/oil-cooling/td-eoc-pricing/
http://killerbeeperformance.com/download/oil-eoc/OIL COOLING.pdf
Also, a link to the tech data for his kit and pricing.
http://killerbeeperformance.com/oil-cooling/td-eoc-pricing/
Yes, agreed on the top port for the best location. I use this port too, so I put a Tee there to get the sensor in the game.
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Michael, I've ran Eisenhower pass numerous times with a 13ft drop in camper, sometimes towing another camper behind it. Something I never would have thought about. There was one time my BOV malfunctioned and I had a huge boost leak running up the west side. This caused the coolant to hit about 240°F by the time I was to the top. Got stopped in traffic after that and noted my oil pressure was almost touching the red tick mark
Another OUCH!!! I once blew a boost boot off coming up the west side. Black smoke everywhere! I pulled off right away and was luckily able to fix it before continuing on.
Any of you that are reading oil temps at or below coolant temp (when at operating temp) are taking the measurement from the wrong spot.
This could be very correct. Never seen the oil temps bellow what the ECT was in a fully warmed up vehicle yet.
I read that sometime back. Interesting. Thanks for posting Brandon.
I didnt know i put it in the wrong hole until after I was out of beer.
http://www.duramaxdiesels.com/forum/showthread.php?t=24994&highlight=oil+temp+sensor
http://www.duramaxdiesels.com/forum/showthread.php?t=24994&highlight=oil+temp+sensor
I don't think mine is there, been 2 years since I installed it.... so I will be moving it. Are all the ports the same threads? (take that plug out and switch it real quickly)....
Thanks Brian, due for an oil change so I'll switch them then and report back temp differences...