Covering Durango grille in winter to raise engine oil temperature

wwillson

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I am trying to wrap my mind that oil and coolant temperature are not at least equal regardless of outside temperature. Does Durango have oil cooler and oil cooler thermostat?
The Durango has an engine oil cooler with a good supply of coolant coming right from the radiator. Unfortunately, no oil cooler thermostat. To me, this is a design flaw. Why run around all winter with the oil pump in high pressure mode?
 
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The Durango has an engine oil cooler with a good supply of coolant coming right from the radiator. Unfortunately, no oil cooler thermostat.
So it is fluid/fluid oil cooler (heat exchanger), not air/fluid oil radiator?
I guess they did not think this through all the way.
 

BlueOvalFitter

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I cover most of the grill on my Durango in the winter to reduce the air across the radiator, in an attempt to get the oil temp above 165F. Below 165F the oil pump is always on the high pressure side and above it's on the low pressure side. I see no need to run around constantly with 90 pounds of oil pressure. This can be a bit tricky because you can overheat engine. I've experimented for several years and know how much much of the grille needs to be covered given the ambient temperature.

I recently drove about 600 miles in one day where the outside temp didn't get above 0°F and was as low as -10°F. The pictures below show the oil temp and outside air temp after about 2 hours of driving on the interstate. The high side of the oil pump kicks in if the engine oil temp is below 165°F. I was able to keep the oil temp higher than 165, but it never got higher than 175°F. The water temperature indicator was normal or just below the entire time.

My guess is that a portion of the cold water coming from the radiator passes directly through the oil cooler.

If you cover your grille, do it a little bit at a time until you know what you can get away with.

Sorry for the blur

View attachment 44959

This is how much I covered - I figure it's about 90% of the surface area. The entire lower portion is blocked.

View attachment 44960
Mr. W, do you tow anything with said truck? And, if so, do you still block the air from entering thru the grill?
 
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I am trying to wrap my mind that oil and coolant temperature are not at least equal regardless of outside temperature. Does Durango have oil cooler and oil cooler thermostat?
Oil temp was nearly always lower than the coolant temp in my 04 F150 with the 5.4 when temps were cool - like below freezing. I always attributed that to the relatively large sump (for the time) that was very exposed to airflow under the truck. Also seemed that the typically lower oil temps meshed with the 5w20 oil it used...

In temps like we have now, (below zero), I could drive for 2+ hours and the oil.temp might break 170. Coolant temp was 190-195.

The 4.6 3v in our explorer is similar - a bit higher temps since the sump is 1 quart smaller...
 
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Fluid/Fluid
Yeah, design flaw. BMW has it on X5 and X3 with N52 engines. But, it is DME controlled thermostat and water pump ( 4 different temperature settings, 110c for cruising, 80c for hard operations and some in between). They should go with regular oil radiator and thermostat.
 
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Oil temp was nearly always lower than the coolant temp in my 04 F150 with the 5.4 when temps were cool - like below freezing. I always attributed that to the relatively large sump (for the time) that was very exposed to airflow under the truck. Also seemed that the typically lower oil temps meshed with the 5w20 oil it used...

In temps like we have now, (below zero), I could drive for 2+ hours and the oil.temp might break 170. Coolant temp was 190-195.

The 4.6 3v in our explorer is similar - a bit higher temps since the sump is 1 quart smaller...
It is cost savings. I have almost 8qt in 3ltr engine sump, but there is no way while cruising that oil temperature drops below 100c, and I just got back from skiing. Driving downhill, stick shift, braking with engine, temperature around 5 degrees, stubbornly set at 100-105c.
 
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Yeah, design flaw. BMW has it on X5 and X3 with N52 engines. But, it is DME controlled thermostat and water pump ( 4 different temperature settings, 110c for cruising, 80c for hard operations and some in between). They should go with regular oil radiator and thermostat.
It’s designed to also help heat up the oil for improved fuel economy. But yeah, my 300 never really got above 160F-170F either, didn’t seem to bother it though and it would switch over and run at ~30psi.
 
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It’s designed to also help heat up the oil for improved fuel economy. But yeah, my 300 never really got above 160F-170F either, didn’t seem to bother it though and it would switch over and run at ~30psi.
Absolutely. It is primary reason why they install that. But, they didn’t think through cooling part. IMO, some kind of thermostat control should be there, mechanical or electric.
 

OVERKILL

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Absolutely. It is primary reason why they install that. But, they didn’t think through cooling part. IMO, some kind of thermostat control should be there, mechanical or electric.
Works fine on the larger 5.7L and 6.4L engines, per the pic I posted earlier in the thread. I suspect the smaller engine just doesn't make enough heat, in which case the OP's workaround is appropriate.

I had a similar situation with my M5 during the winter months, even with a thermostatically controlled oil cooler, the oil would not get up to operating temp. The engine was of course all aluminum and had a cooling system sized for track use.
 
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Works fine on the larger 5.7L and 6.4L engines, per the pic I posted earlier in the thread. I suspect the smaller engine just doesn't make enough heat, in which case the OP's workaround is appropriate.

I had a similar situation with my M5 during the winter months, even with a thermostatically controlled oil cooler, the oil would not get up to operating temp. The engine was of course all aluminum and had a cooling system sized for track use.
Understand. It is just applying same components across the line up.
i am not questioning solution, it is tried and proven. I am not sure whether bumping viscosity would creat bit more heat, just to go over that threshold when pump is under stress.
 
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Absolutely. It is primary reason why they install that. But, they didn’t think through cooling part. IMO, some kind of thermostat control should be there, mechanical or electric.

Most heat exchangers run hot coolant through them, to keep the oil and coolant temps more equal. In case of the Durango it's strictly a cooler it seems
 
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Most heat exchangers run hot coolant through them, to keep the oil and coolant temps more equal. In case of the Durango it's strictly a cooler it seems
Yes, but, coolant will warm up much faster, so it will help getting oil to certain temperature even in really low ambient temperature. But, IMO they overdid it, or just wanted to use same parts that are made to fit largest engine they will but in vehicle. IMO this system is really good if there is some thermostatic control. In BMW this works really good, but than people are not happy bcs. it is more complex.
 
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