I think many people would be shocked at just how high the automatic transmission temperatures can get. For about the last three years I have been studying the relationship between transmission temperatures and the diesel powered trucks. Temperatures really become a issue when towing as most would expect, but they also become a problem with city traffic, or anytime you are forced to drive slow with repeated starts. There are large amounts of heat given off with every gear change, and every time the torque converter locks-up. This heat is usually not a problem, as the truck can absorb the heat and dispense of it through normally channels (heat exchangers,coolers). Which is OK if you are simply running through the gears and getting up to highway speeds, But if you are stuck in traffic or any other place that requires very slow speeds, these constant gear changes simply overwhelm the trucks ability to maintain a safe transmission fluid temperature. And by safe fluid temperature, I mean anything under 180°. Of-coarse, adding the additional load of a trailer or heavy payload will only make these temperatures soar faster and higher.
While pulling our test trailer, I have found as few as 4 traffic red lights in a row, caused the temperature to raise into the hot zone (temps of 190° and more), that's not much margin. Also , once the transmission fluid hits 190° in stop and go traffic, the truck losses it's ability to cool the transmission. The reserve built into the trucks cooling system is compromised, and starts effecting other engine coolings systems, like water temperatures and engine oil temperatures. Also, anyone that has ever sat in traffic could see how the trucks air conditioning system is effected, it just doesn't seem to cool anymore. This is all do in part to the transmissions inability to maintain itself in slow traffic situations, during summer like weather.
The shocker wasn't how fast the towing vehicle overheated, but how much the non-towing truck was effected. Most including myself, didn't think there was an issue with a empty truck and automatic transmission fluid temperatures, but we were wrong. The empty truck mimicked the towing truck, although it took much longer for the temps to reach 190°, once there they too over-whelmed the trucks ability to cool itself. The key seems to be keeping the temps from rising above 190°, and the only way to do that is to run an axillary transmission fluid cooler.
Before I began my studies, I thought the reason I lost my first transmission was because it was weak or somehow outdated, but that was no where near the truth. What happened to my first transmission was it simply failed due to heat, it burnt itself up. Since then I have had the experience of tearing down a Dodge transmission, and they are very robust and well built pieces. But so is the Cummins, and allow it to overheat and it to will fail.
This is the reason I came out with the SUPER COOLER, it directly adds cooling capacity to the system that needs it the most, the transmission. It will not over-cool, which is a problem in it-self during winter conditions, but allows the transmission to function as normal with the safety blanket of a 2-stage auxiliary cooling system. Under normal conditions, the additional cooler helps keep temperatures down, some 25-55° cooler then the same truck without the cooler. And when you need it the most, the 2nd stage of cooling kicks in and again lowers temperatures another 25-50 °. This stage uses a electric fan, which is fully automatically controlled by a built-in thermostat. Once temperatures raise above 165°, the fan kicks on to help control any potential overheating problems. This system has worked great for me, I have been testing it for the last three years and have never had a overheating problem since. I have abused my transmission with pulling a triple axle, 16,000lb trailer under some of the most horrid conditions, with no problems at all. So, what began three years ago to prove the Dodge transmission was junk and outdated, has now turned into proving that transmission was and is still a very good and robust automatic transmission, just it needs a hand in the cooling department. And with my SUPER COOLER it's a great transmission. For more info in the SUPER COOLER visit us at
www.proweldperformanceparts.com.
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