[77newell]

What Chester said about heat limits is consistent with what I've learned from Allison sources. The temperature limit at which the transmission begins to limit operations is 270 degrees as measured in the sump. the temperature reported on our dash gauges is the temperature before the fluid goes to the cooler and is almost certainly the hottest point in the circulation, and is certainly hotter than the sump. I've heard that 350 or 375 is OK on our dash gauges, though frankly that would freak me out. It's nice to know the transmission itself has a temperature sensor linked to the ECU to warn us via the "check trans" light before things get expensive.