My 2004 Hummer overheated last week after about five minutes of driving. The coolant overflow was belching out an orange/brown froth and it was shifting like hell. The transmission dipstick is a frothy pink instead of cherry red like I am used to seeing.
It seems obvious it is the transmission oil heat exchanger and the coolant tank are compromised and now being mixed...
Could it be anything else?
Any way to confirm it at a home garage?
How common is this with the 2004 H2 Hummers?
How difficult is the radiator removal job? I changed the power steering pump last year and you have to remove a ton of accessories for that job...
Former Corvette mechanic for midyears up to 82' so I have the tools.
Any help is greatly appreciated.

 

It is a very well known issue for all years. The in radiator tranny cooler has been known to cause issues resulting in what you're describing. From what I've read the antifreeze plays havoc on the tranny clutches requiring a rebuild.


Most people will bypass the tranny cooler and install a more efficient aftermarket tranny cooler in front of the radiator.


Good luck, let us know what happens!