Forum Discussion
Wes_Tausend
Mar 16, 2014Explorer
...
sheripoms,
The tranny cooler and engine oil cooler are similar items and could probably be interchanged in function. Both remove heat from oil. If your Tahoe will be working hard, it will benefit from upgrading both coolers.
Regular petroleum oil begans to break down around 275 degrees Fahrenheit. The oil becomes thicker and therefore less flows at the pre-set oil pressure, robbing bearings of needed cooling. In the case of auto trannies, the control valving will not work right, possibly leading to slow slipping shifts and other problems. Synthetic oils resist heat up to around 500 degrees F and are less susceptable to lube failure. Synthetic oil was developed for high heat aircraft turbine engines.
Heavier piston engine loads cause more bearing heat and require more cooling flow to remove said heat, so too thick of oil will fail in this regard. One thing to keep in mind is that some molecules are subjected to extreme heat even when the average temp is within reason. So oil continuously breaks down over time and should be changed at suggested OEM service intervals. Heavy towing requires more frequent intervals for this reason. In this way, oil does wear out.
Some years ago ('90's?), GM quit installing oil coolers in their Corvette and sent them out of the factory with Mobil 1 synthetic already installed. Most owners kept this up since the book called for it. The idea was that synthetic protected the cars during high speed road racing just as well as the former oil coolers. If it is good for a hard working Corvette, it is good for a hard working Tahoe.
Do not be afraid of synthetic weight grades. In simple terms, an oil designated as 15w40 (for example) means that the oil will not get thicker than 15 weight when cold, nor thinner than 40 weight when hot. Synthetic is simply more stable than a straight weight oil. Straight weight oils vary widely in viscosity (thinness) and are seldom used anymore. Install the seasonal oil weight that the owners manual calls for, be it synthetic or ordinary refined petroleum oil. By the way, the "w" in 15w40, or 5w20, stands for winter, the first use of such oils until it was realised that it worked better for cold starts all year.
I own a Ford V-10 that has come with a built-in oil cooler since about 1997. The engine was designed for hard work and auto trannies packaged with it all have factory tranny coolers also. Ford initially called for 5w30 oil (all season moderate climates) and then changed that to 5w20 when it became apparent that oil was not circulating fast enough, especially to the overhead cams.
Lastly, an engine that is never working at extreme heat levels won't benefit from more expensive synthetic. Consumer reports did an interesting study on this.
Wes
...
sheripoms,
The tranny cooler and engine oil cooler are similar items and could probably be interchanged in function. Both remove heat from oil. If your Tahoe will be working hard, it will benefit from upgrading both coolers.
Regular petroleum oil begans to break down around 275 degrees Fahrenheit. The oil becomes thicker and therefore less flows at the pre-set oil pressure, robbing bearings of needed cooling. In the case of auto trannies, the control valving will not work right, possibly leading to slow slipping shifts and other problems. Synthetic oils resist heat up to around 500 degrees F and are less susceptable to lube failure. Synthetic oil was developed for high heat aircraft turbine engines.
Heavier piston engine loads cause more bearing heat and require more cooling flow to remove said heat, so too thick of oil will fail in this regard. One thing to keep in mind is that some molecules are subjected to extreme heat even when the average temp is within reason. So oil continuously breaks down over time and should be changed at suggested OEM service intervals. Heavy towing requires more frequent intervals for this reason. In this way, oil does wear out.
Some years ago ('90's?), GM quit installing oil coolers in their Corvette and sent them out of the factory with Mobil 1 synthetic already installed. Most owners kept this up since the book called for it. The idea was that synthetic protected the cars during high speed road racing just as well as the former oil coolers. If it is good for a hard working Corvette, it is good for a hard working Tahoe.
Do not be afraid of synthetic weight grades. In simple terms, an oil designated as 15w40 (for example) means that the oil will not get thicker than 15 weight when cold, nor thinner than 40 weight when hot. Synthetic is simply more stable than a straight weight oil. Straight weight oils vary widely in viscosity (thinness) and are seldom used anymore. Install the seasonal oil weight that the owners manual calls for, be it synthetic or ordinary refined petroleum oil. By the way, the "w" in 15w40, or 5w20, stands for winter, the first use of such oils until it was realised that it worked better for cold starts all year.
I own a Ford V-10 that has come with a built-in oil cooler since about 1997. The engine was designed for hard work and auto trannies packaged with it all have factory tranny coolers also. Ford initially called for 5w30 oil (all season moderate climates) and then changed that to 5w20 when it became apparent that oil was not circulating fast enough, especially to the overhead cams.
Lastly, an engine that is never working at extreme heat levels won't benefit from more expensive synthetic. Consumer reports did an interesting study on this.
Wes
...
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