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