[Coloh2hummer]

i have replaced the thermostat so, now where? Could it be the radiator clogged, should I back flush it? Also, the hummer doesn't have the trans cooler mod, is that something I should consider? Someone was saying to unclog the remote radiator tank???

[hummer_on_fumes]

The obvious thing to check is the coolant level. That will tell you if your radiator is leaking somewhere. Is the engine or trans overheating? Yes you should definitely put in a separate trans cooler. The oem radiator is a ticking time bomb to destroy your transmission when the fluids mix

[Coloh2hummer]

Ok, the trans temp gage is broken. I have checked the coolant numerous times and it hasent changed. Eng temp gage will go full hot if you keep going, I pulled over and turned the eng off. I checked the eng temp with an infrared temp checker and the gage is spot on! I guess I could check the trans temp with the infrared?

[calif phil]

What's the mileage? If over 100,000 I would buy a new quality radiator.

[tharber]

It could be anything from a bad water pump, bad radiator or bad gauge.

Tim

[Dry Heat]

It could be something else. Mine started overheating and went in creep mode. I found out the catalectic converter had gone bad and the whole system was shutting down.