Just what is a "hot flush"?

Mike L.

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Aug 12, 2006
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Hot trans fluid pumping through the cooler lines under pressure.
Trans coolers are designed to contract when cold to help heat the fluid quicker. They then expand when hot and allow normal flow. Blowing air or solvent through them cold will not dislodge crap in the cooler. When the trans fluid gets hot and the cooler tubes finaly expand, the crap comes out. Many times it's too late and trans valves and solenoids will act up causing problems and premature failure. Hot flush machines are a must. The one we use here at the shop costs over 6K. Money well spent and it paid for itself many times over.
 
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TheBac

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I moved this into its own thread in Trans Talk. Ive always wondered what a transmission "hot flush" was all about too. Thanks Mike. :)
 
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pavetim

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Jan 10, 2011
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I will have to see of any shops have this machine cause if I get an inglewood Trans it voids warranty if I don't get this done
 

2004LB7

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Dec 15, 2010
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I will have to see of any shops have this machine cause if I get an inglewood Trans it voids warranty if I don't get this done
some replace the lines and radiator to get around that. could be the same cost or more but look into it as an alternative if you can't find anyone with the machine