| I just posted a conversation I had with a ZF-certified service guy this week (one of very few in the USA). We discussed high-mileage ATF changes, process and (non)issues like varnish. Have a read:
I don't think that the reasons FOR changing the ATF would be any different for the GM tranny. I have heard (though I would question the source) that high levels of metals-based contaminants flowing through high-mileage ATF exacerbates the solenoid failures that do occur in some model years of the GM tranny. Again, I can't substantiate that.
Last edited by Makakio; 06-10-2009 at 10:49 AM.