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Old 05-05-2012, 09:07 AM   #1
88Jimmy4x4
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TH350 trans to radiator cooling lines questions

okay got my engine and trans in the 76 truck finally.......I bought new radiator cooling lines and Im not sure what line goes where. My GM manual says TH350 bottom connection goes to radiator and top connection comes from radiator.

My question is on the radiator is the top connection the inlet or is that the outlet/return to trans?

inotherwords.....does the bottom line on trans go to bottom of rad.....likewise top line on trans to top conn on rad or vice-versa?

I have searched the internet and have gotten mixed reults
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Old 05-05-2012, 11:37 AM   #2
badpontiacs
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Re: TH350 trans to radiator cooling lines questions

I didnt think it mattered.
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Old 05-05-2012, 11:47 AM   #3
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Re: TH350 trans to radiator cooling lines questions

Summit labels them as what goes where and does what. I just bought some. I would imagine that cooler juice would be on the bottom of the radiator, thus the lower line would be coming from the radiator. That's just my thought process.
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Old 05-05-2012, 01:39 PM   #4
ron350
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Re: TH350 trans to radiator cooling lines questions

On my 75 model the top radiator fitting connects to the top transmission fitting.

Looks like top to top and bottom to bottom.
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Old 05-05-2012, 02:09 PM   #5
kmfb
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Re: TH350 trans to radiator cooling lines questions

mine was top of tranny to bottom of radiator and vice a versa
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Old 05-05-2012, 02:25 PM   #6
88Jimmy4x4
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Re: TH350 trans to radiator cooling lines questions

Thanks guys, seems everyone is different lol
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Old 05-29-2012, 01:17 AM   #7
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Re: TH350 trans to radiator cooling lines questions

There is a couple of ways to tell which is which, generally the pressure side of the transmission is the line from the front of the transmission which goes to the bottom radiator connection (The other is to start a cold engine, place in Drive for 10 seconds to activate the transmission pump and shut off the engine. The cooler of the two lines is the return line which should be the top radiator connection). The top line is the return line which goes to the back of of the transmission. Good luck. G.
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