Anyone knows what is my transmission return line?

[chaseww111]

Hello, I'm looking for if anyone knows what transmission coolant line is my return line on my Buick 2008 Lucerne with a 3.8 engine. I have a 4t65e transmission. I have been getting many mixed reviews. Is the top line of the radiator the return line back to the transmission? I was told that the bottom line would be the feed line and the top line would be the return line. Please if anybody could confirm that I would really appreciate the help. Thank you

 

[2007LucerneCXL]

Bottom is returned, what is being done as that may help with additional information.

 

[chaseww111]

Bottom is returned, what is being done as that may help with additional information.
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Ok, l have had 3 people saying its the lower and 4 saying its the upper that is the return line. I am so confused? But you are saying its lower is the the return. I will believe you then. Even the dealership did not know. Lol..... Thank you

 

[02LTD2.0]

Hello, I'm looking for if anyone knows what transmission coolant line is my return line on my Buick 2008 Lucerne with a 3.8 engine. I have a 4t65e transmission. I have been getting many mixed reviews. Is the top line of the radiator the return line back to the transmission? I was told that the bottom line would be the feed line and the top line would be the return line. Please if anybody could confirm that I would really appreciate the help. Thank you

Why do you ask?

 

[chaseww111]

Why do you ask?

Cause i am having a trans cooler installed in front of the condenser and i would need to know the return line to hook up on it and back to return on trans. Thank you

 

[02LTD2.0]

That makes sense....thanks.

 

[chaseww111]

That makes sense....thanks.

I have been trying to get the right answer which one is the return line, and i have a alot of different answers. 6 people now say its the top radiator coolant line and 5 people are saying its the bottom radiator coolant line as the return line. Its very confusing for sure.....😡 Even the dealership does not even know....

 

[02LTD2.0]

Feed is at the top and return is at the bottom. It makes sense when you consider how things work.

 

[chaseww111]

Feed is at the top and return is at the bottom. It makes sense when you consider how things work.

I agree with you. I had 2 transmission techs and 3 mechanics said the return line is at top, 😭 i will listen to you. I guess the transmission cooler would atill work no matter what either way thank you

 

[2007LucerneCXL]

Depending if the cooler is to be a stand alone or to be used in tandem with the original radiator can make a difference in efficiency along with the style of transmission cooler. Just a note as the installation of the cooler it may be something to consider in changing the fluid and filter at the same time. There are, assuming it's the 4T65E, addtional updates that should be looked at while the transmission fluid is out.

 

[chaseww111]

Depending if the cooler is to be a stand alone or to be used in tandem with the original radiator can make a difference in efficiency along with the style of transmission cooler. Just a note as the installation of the cooler it may be something to consider in changing the fluid and filter at the same time. There are, assuming it's the 4T65E, addtional updates that should be looked at while the transmission fluid is out.

It will be used in tandem with the radiator. I guess it would then have to be definitely the return line. I would just wish i got one answer which is the return line. Many have said its the bittom radiator line and many saud its the top radiator line that is the return. I just want it right. I tried the feeling the kines when warm but that's very hard, i could not tell. Someone said to start the car up while someone puts the bottom coolant hose in a jug and seal it, so it does not splash out to see if it shoots in the jug. I guess i would yry that ...🥺

 

[2007LucerneCXL]

Top line on the radiator is the outbound, hot, line from the transmission and bottom, cool, line is the return to the transmission. Same as the coolant from the engine to the radiator.

 

[chaseww111]

Top line on the radiator is the outbound, hot, line from the transmission and bottom, cool, line is the return to the transmission. Same as the coolant from the engine to the radiator.

Great, i will do it that way. I will install the bottom line into the trans cooler then out of the trans cooler back to transmission. Thank you very much