As any overlander or road tripper knows, it’s important to keep unnecessary wear and tear to your hard working vehicle to a minimum. We’ve been noticing that the transmission temperature in our truck was sometimes creeping above 270° F (132° C), particularly when climbing long grades. We were concerned since these temperatures are approaching levels that could damage the transmission. After researching this issue on various Chevrolet Silverado Duramax diesel forums it became clear that we needed a larger transmission fluid cooler and from everything we read one choice stood head and shoulders above the rest: the “Mike L” cooler, now known as the
Performance Transmission Cooler sold by Pacific Performance Engineering (PPE).
The cooler is larger than the factory installed version and the increased surface area allows for better cooling. The company kindly sent us a kit, which is basically plug and play. Just remove the OEM cooler and, using the included hardware, swap in the new larger cooler. It took less than 30 minutes for a mechanic to install it and it was so easy that Eric probably could have done it himself.
The PPE cooler looks simple but it instantly delivered noticeable transmission temperature reductions in daily driving. Without the PPE cooler our temperatures in standard driving were around 180° F (82° C). Now our standard driving temperatures are usually around 150° F (65° C).
On Saturday we put our new PPE Performance Transmission Cooler to the real test when we traveled from near sea level steeply up to more than 9,000 feet (3,000 meters) along a very slow and windy road. Over the course of three hours in steep, slow conditions our transmission stayed at least 20-30° F (11-17° C) cooler than it has been on similar climbs before installing the PPE cooler. This is well within its comfort zone which is a relief for us and for our truck.
Another way to lower our transmission fluid temps even more is to install PPE’s Heavy Duty DEEP Aluminum Transmission Pan. This larger transmission fluid pan increases the transmission fluid capacity by four quarts: more fluid equals lower temperatures.
However, this pan is more than four inches deeper than the standard pan which means it would hang down about three inches below the chassis frame, reducing our road clearance. Since some of the roads we drive on require all nine plus inches of clearance that we currently have on our truck, we were afraid that this deep pan could lead to potentially catastrophic damage if we were to smash the unprotected pan on something in the middle of nowhere.
PPE does, however, make a standard profile transmission pan that’s better than the OEM pan and we will be making this vehicle upgrade as soon as visiting friends or family can bring it down to us from the US. Hint, hint.