6 Even with extra coolers, deeper transmission pans and enlarged lube holes, transmissions can still suffer overheating from external sources. Custom exhaust systems can often be routed too closely to the torque converter and transmission (in effort to keep the exhaust high and out of the way) and the heat soak into the transmission can be severe enough to fry one. After all my efforts to cool my transmission down, it was obvious that the exhaust was heating up the transmission on my truck. This is why Design Engineering (DEI) makes exhaust wrap and heat shroud products. I got my hands on its new Titanium exhaust wrap, some steel locking ties (to hold the wrap), and a couple 3-foot lengths of Heat Shroud.