4L80E fluid lines - opposite of 4L60E?
#1
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High on diesel fumes
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From: Phoenix, AZ
Are the fluid lines that come out of the 4L80E opposite of the 60E? Which goes out to the radiator and which is for fluid coming back in to the trans? My tranny runs lots hotter than the 60E did, and I'm thinking that it's because I have the fluid routed to the external coolers first then through the radiator. The tranny temp seems to always stick close to engine temp (saw 225 towing this weekend, and thats about where coolant temp was too), where as before it rarely got above 165 or 170 or so.
#7
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High on diesel fumes
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From: Phoenix, AZ
Originally Posted by Vince @ FLT
What year is your case? All center lube cases the front line is pressure. If it is an early case bottom line is pressure. Good luck! 

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#9
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High on diesel fumes
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From: Phoenix, AZ
Originally Posted by parish8
you can tell wich line is the feed by starting the truck when cold and puting your hands on the lines. see wich one gets warm first. thats the feed line.
Duhhhh I can't believe I didn't remember that. Thanks for reminding me!
#10
Originally Posted by parish8
you can tell wich line is the feed by starting the truck when cold and puting your hands on the lines. see wich one gets warm first. thats the feed line.
You are correct about the lines getting warm. I never look at it that way but that is a good idea.



How come you never went when I was there?