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Discussion Starter #1
On my way home from work today I got about 2 miles from my house and noticed my trans temp gauge was in the red. Also got a notification on the dash stating "trans fluid hot". As I slowed down for the stop sign it downshifted as though it were in tow/haul mode even though tow/haul was not engaged. For the remainder of the 2 miles to get it home it acted the same way. I just got my truck back from a body shop after hitting a deer. They did replace my trans cooler and both lines going to it. Checked the fluid... its good. No leaks that I could find. Any ideas on what this could be?
 

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Could be overfull? Sounds like you were slipping bad. I would try 2 change your spin-on filter & see how much crap is on the magnet. I am betting your tranny was in a safe mode that is why it was shifting that way. Maybe the shop took your truck out for a joyride. How far did you drive before the tranny was really hot? Was the temp normal when you picked it up?
 

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I also wonder if they blead all of the air out of the trans cooler. It could be air locked. If it ran fine before the deer hit and now it does not.
 

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If the level is over the hot mark that will cause it to overheat-- also if the cooler line is plugged or crimped that will reduce the cooling.

Also check the shift linkage, it is possible that you are not going into the correct gear.
 

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sounds like they covered it all, good advice guys...... let us know what you find out
 

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Discussion Starter #6
Checked the fluid level and its not above the hot line. Changed the spin on about 5k ago. Drove to work yesterday, about 120 miles, hard and temp was fine. On the way home today it wasn't driven nearly as hard and it heated up like that less than 5 miles from home. Shift link looks good to me. Couldn't see any crimps in any lines. How do you check to see if its been bled all the way down?
 

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You are probably good on the air thing if you have driven that far without issues. I would check to make sure the spin on is fine or if there is blockage in the cooler lines.
 

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Discussion Starter #8
And what's the best way to check for a blockage in the lines?
 

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Pull them off and blow thru them. Then check the cooler itself. I would be willing to bet something got in the system. I would cross your fingers and check the spin on first. Hopefully it caught whatever it is.
 

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feels like T/H mode because your trans is in "HOT" mode.
 

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Discussion Starter #11
So I checked my spin on and it looked brand new. So I went under the hood to trace the lines. After removing my air box for a better view I found the problem... a nice brand new pair of line crimpers sitting where I couldn't see without the air box off. Line was pinched tight! Removed them and went for a ride. Seems ok now. Hope that mechanic from the body shop won't miss them too much! Thanks for all your input fellas!
 
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