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Transmission Cooler Installation Important Questions

robrileyw

New member
Hello to all, I have a 2000 Pontiac Grand Prix 3.8l w/ a 4T65E transmission that has about 82k miles on it. I will be installing an Imperial Transmission Cooler and need some reassurance on a couple things...

1) Is the transmission supply line run into the bottom of the radiator & the transmission return line coming from the top of the radiator back to the transmission??

2) Should the transmission cooler be installed in series with the factory cooling or should the cooler be installed as a stand alone transmission cooler?? (I live in upstate NY which winter temps can get as low as 20 to 30 below)

3) If installing the transmission cooler in series, what would be the appropriate routing of the complete trans cooling set up.....Should it go like this?? Transmission supply line>bottom of radiator>top of radiator>bottom of external trans cooler>top of external trans cooler>transmission return line ??

4) Should I use the stock clamps that came with the trans cooling kit or use a better alternative on all connections??

I appreciate any and all feedback on all 4 questions, Thanks ahead of time!!
 


the top line should be the tranny fluid in. the bottom is the out/back to the tranny. so come off the bottom line of the rad to the cooler, then from the cooler back to the tranny.

being up state NY id run them in series due to the cold temps up there, your tranny still needs to be warmed up, ice cold is almost as bad as super hot.

seen people use hose clamps, i dont trust that unless the hard line is flared.

had a friends car burn in my drive way from a blown off rubber line on the trans cooler line to the rad. not flared, smooth pipe. came right off sprayed all over the exhaust and fire!
 
See I'm confused, this write up says the opposite with regards to supply and return lines on grand prixs ( http://www.grandprix.net/upgrades/cooler.html )....but I'm definitely going to run the cooler in series with cold temps, and all hard lines are flared so idk if I should worry about other alternatives to regular clamps that came with the kit...

Anybody else have any feedback on the supply and return lines on a 2000 grand prix?? I guess worse comes to worse and I can just touch both lines after warmed up and should be able to figure out which is hot (supply) and cold (return)...
 
most of the time hot enters the top of a cooler, cold leaves the bottom, just like the rad.

my brother and i flushed his yukon tranny, we took the top line off put a barbed fitting on the line then a clear tube to a pail, it pumped from the top line is what im saying. just like the how to he found said.
 
Watch youtube videos of trans cooler's! It looks pretty easy and I plan on doing it in the next few months when it gets warmer out!
 
Rob,

I installed an in-series trans cooler last summer on my 2008 grand prix; hopefully I can provide you with some information:

1) You have it backwards - scotty described it correctly.

2) I live in MN and decided to go in-series so the trans can heat up quicker in the winter.

3) Your final system should be Transmission>line to top of radiator>line from bottom of radiator>your new transmission cooler>Transmission.

4) I ended up using barbed/flared copper male-to-male connectors and hose clamps to splice my cooler into the system.

If you'd like additional information on my approach feel free to ask. I found many youtube and other discussions only somewhat helpful.
 


seen people use hose clamps, i dont trust that unless the hard line is flared.

had a friends car burn in my drive way from a blown off rubber line on the trans cooler line to the rad. not flared, smooth pipe. came right off sprayed all over the exhaust and fire!
I'm glad I saw this so when I do mine I'll flare the ends so that doesn't happen.
 
Rob,

I installed an in-series trans cooler last summer on my 2008 grand prix; hopefully I can provide you with some information:

1) You have it backwards - scotty described it correctly.

2) I live in MN and decided to go in-series so the trans can heat up quicker in the winter.

3) Your final system should be Transmission>line to top of radiator>line from bottom of radiator>your new transmission cooler>Transmission.

4) I ended up using barbed/flared copper male-to-male connectors and hose clamps to splice my cooler into the system.

If you'd like additional information on my approach feel free to ask. I found many youtube and other discussions only somewhat helpful.

For future reference I had the routing messed up in the previous post the CORRECTIONS are below:

1) You have it correct.

3) Your final system should be Transmission>line to bottom of radiator>line from top of radiator>your new transmission cooler>Transmission.
 
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