Adding Trans Cooler LS4 Buick Super
^^^There is a Sticky dedicated to this subject.
^^^There is a Sticky dedicated to this subject.
Seen the posts that siad trans line on tranny, bottom i s low and top is high pressure. Assume best to cut line on low pressure side and splice in cooler.
High pressure out of tranny through radiator, out of radiator through Hayden cooler, back in tranny low pressur line.
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The night we went to do it there was a little confusion on my buddies face so I backed out.. he does most of my work seeing as I'm not even close to being a mechanic haha.. but yes that is what was confusing..

In the above drawing
-the RED LINE is HOT (PRESSURE OUT)from the transmission into the LOWER of the internal rad cooler
-the ORANGE LINE is less HOT OUT from the RAD COOLER to the EXTERNAL COOLER (IN PORT)
-the BLUE is from the EXTERNAL COOLER (OUT PORT) to the RETURN PORT of the transmission
In the above drawing
-the RED LINE is HOT (PRESSURE OUT)from the transmission into the LOWER of the internal rad cooler
-the ORANGE LINE is less HOT OUT from the RAD COOLER to the EXTERNAL COOLER (IN PORT)
-the BLUE is from the EXTERNAL COOLER (OUT PORT) to the RETURN PORT of the transmission
If you look at the transmission in the picture above you will notice that there are 2 fittings on the transmission.
-A horizontal one (return fluid and attaches to the upper rad cooler port)
-A vertical one (heated transmission oil out attaches to the lower rad cooler port)
BOTH lines are pressure lines and the reason for the bottom to top cooling is:
- there is all sorts of material exiting your transmission, some of it is small metal particles and some clutch material. This material likes to stick to the inside of everything as it is sometimes extremely hot. So when you shut down heat rises and will find its way to the top of the cooler and back to the pan easily and some of this material will fall to the bottom while the car sits. Now back to the start up the gush of fluid coming up from the bottom will flush the cooler somewhat forcing the particles into the pan pre filter.
If you look at the transmission in the picture above you will notice that there are 2 fittings on the transmission.
-A horizontal one (return fluid and attaches to the upper rad cooler port)
-A vertical one (heated transmission oil out attaches to the lower rad cooler port)
BOTH lines are pressure lines and the reason for the bottom to top cooling is:
- there is all sorts of material exiting your transmission, some of it is small metal particles and some clutch material. This material likes to stick to the inside of everything as it is sometimes extremely hot. So when you shut down heat rises and will find its way to the top of the cooler and back to the pan easily and some of this material will fall to the bottom while the car sits. Now back to the start up the gush of fluid coming up from the bottom will flush the cooler somewhat forcing the particles into the pan pre filter.
After you re-visit the diagram and discover that the line from the top of the rad cooler to the top of the aux cooler, it actually creates a trap to prevent the transmission internals from emptying back into the pan causing it to overfill the pan and venting out on the ground every time you turn your car off. There is 16 quarts in there and only a 4 quart sump. The same thing would happen if you were to hot in at top and cooler out at the bottom in a single rad cooler install. Now for the two coolers at once, if you live were I live it is the best practice because a cold transmission does as much damage as a hot transmission. So we and most people in a somewhat northern climate actually benefit from this situation. People in the southern climates may and should opt for the external only cooler as in the morning it is kinda warm already.
Last edited by Ill_Born_ss; Mar 14, 2013 at 06:17 AM.



live in central il 