Question about ECT vs EOT
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From: Eagle Mountian, Utah
Question about ECT vs EOT
Ok so I know the spread is not supposed to go over 15. But what about when your climbing 9% grades around 40mph. Truck heats up and the spread goes out of balance. If I were towing it would get even worse. Atm on the freeway doing 70mph its about 10-12 most of the time. Climbing grades unloaded it gets to 19-22. Is that normal for a good oil cooler? Or would a new oil cooler keep the spread below 15 on grades like that?
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From: Scio, OR
When I was driving and climbing hills last summer, I was seeing a spread of about 10-12 degree's. When I hit a hill, the ECT and EOT would go up together, with about the same spread. When I topped over the hill, the ECT would drop faster than the EOT and the spread would go well over 15 degree's, until the ECT settled and the oil caught up with this.
This is normal, in my opinion. However, I think if you're consistently pulling you should stay in that 15 degree range. It's when you suddenly stop pulling and let off that the ECT cools off much faster than the EOT and you get a bigger spread that's OK.
This is normal, in my opinion. However, I think if you're consistently pulling you should stay in that 15 degree range. It's when you suddenly stop pulling and let off that the ECT cools off much faster than the EOT and you get a bigger spread that's OK.
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Joined: Dec 2003
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From: Stuttgart, Ar
IMHO you have some restriction in your oil cooler. 19-22 spread is very borderline but keep it in perspective as to how hot the overall oil temperature gets.
Like David, I think too many people don't take into account the different rates at which the two fluids heat and cool and think they have a bad cooler just because they get a 15* temperature spread.
Like David, I think too many people don't take into account the different rates at which the two fluids heat and cool and think they have a bad cooler just because they get a 15* temperature spread.
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Joined: Oct 2010
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From: Ouray, CO
IMHO you have some restriction in your oil cooler. 19-22 spread is very borderline but keep it in perspective as to how hot the overall oil temperature gets.
Like David, I think too many people don't take into account the different rates at which the two fluids heat and cool and think they have a bad cooler just because they get a 15* temperature spread.
Like David, I think too many people don't take into account the different rates at which the two fluids heat and cool and think they have a bad cooler just because they get a 15* temperature spread.
If the t-stat is not functioning properly,
the temp spread is meaningless.
Remember we are trying to detect a restricted coolant flow through the OIL cooler to prevent overheating the EGR cooler (hot exhaust gasses with insufficient coolant flow to pull out the heat fast enough to avoid melting in the internals). So, the oil's performance @ 220* isn't the main issue with the 20* delta. But heavily loaded it's normal for the engine to get hotter and cool off at different rates as Partsman states.
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From: Green Lane, Pa.
Ok so I know the spread is not supposed to go over 15. But what about when your climbing 9% grades around 40mph. Truck heats up and the spread goes out of balance. If I were towing it would get even worse. Atm on the freeway doing 70mph its about 10-12 most of the time. Climbing grades unloaded it gets to 19-22. Is that normal for a good oil cooler? Or would a new oil cooler keep the spread below 15 on grades like that?
Depending on how the coolant temp is running their should not be that much spread driving 70 on level ground unloaded. If the coolant temp is in the high 180's low 190's and your oil temp is 10-12 higher cruising 70 you are getting a blockage. In the summer you can expect 3-4 more deg. spread.
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From: Eagle Mountian, Utah
Yeah the therm reachs 190 and pretty much sits there. Unless I climb grades, on a climb my ect will go to about 204ish and the eot will stay 218-227 range. That's while climbing, after I stop the spread goes a ton higher until it cools off.
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Hotshot
Joined: Dec 2003
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From: Stuttgart, Ar
Then I would say it's oil cooler time IF you haven't tried flushing it first
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Joined: Apr 2007
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From: Almost Heaven
I just got to try out my new oil cooler and thermostat this weekend. Traveling down I-79 empty I was running 190-192 ect and 196-200 eot. With a full load (tossed, not stacked) of firewood I was running 192 ect and 200-202 eot. Grades and all at 2000 rpm.
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