2002 Lesabre limited- trans cooler return line at trans location

If you can find a picture of a radiator for your vehicle, review the part of the image where the lines attach. They may have a reference number in the image. I just checked and Rock Auto does not seem to have any with reference numbers.

If you use Google for "transmission oil cooler fittings" you will see a bunch. What you need to do is to find a way to measure yours, and to determine which style of fittings are being used.
 
If you can find a picture of a radiator for your vehicle, review the part of the image where the lines attach. They may have a reference number in the image. I just checked and Rock Auto does not seem to have any with reference numbers.

If you use Google for "transmission oil cooler fittings" you will see a bunch. What you need to do is to find a way to measure yours, and to determine which style of fittings are being used.
Ok I'll try to find out. Maybe I'll post a question on this forum and see if anyone knows.
 
If you can find a picture of a radiator for your vehicle, review the part of the image where the lines attach. They may have a reference number in the image. I just checked and Rock Auto does not seem to have any with reference numbers.

If you use Google for "transmission oil cooler fittings" you will see a bunch. What you need to do is to find a way to measure yours, and to determine which style of fittings are being used.
I'm showing I have this female fitting Amazon.com: GM Genuine Parts 19130039 Automatic Transmission Fluid Cooler Line Connector : Automotive
And this male fitting
 
If those are your fittings, you now have the means to plumb it however you need to, and still be able return it to stock, all without cutting the stock lines or hoses.
 
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If those are your fittings, you now have the means to plumb it however you need to, and still be able return it to stock, all without cutting the stock lines or hoses.
Thos are the stock fitting that I have, well they are similar to what's shown in the photo. Do you know how I would fit 3/8" hose onto those fittings?
 
The adapter you need will need to have only one side with the matching threads or type of attachment. The other side can be a barbed fitting so you can attach a hose and then clamp it down. You'll want one with a single, rounded barb and enough flat surface beyond it so you can clamp it. You don't want one with multiple sharp barbs since those are intended for hoses without clamps.
 
The adapter you need will need to have only one side with the matching threads or type of attachment. The other side can be a barbed fitting so you can attach a hose and then clamp it down. You'll want one with a single, rounded barb and enough flat surface beyond it so you can clamp it. You don't want one with multiple sharp barbs since those are intended for hoses without clamps.
Thanks
 
You may want to go to either an auto parts store or a hardware store that sells hydraulic fittings.

Once you find any fitting that will properly screw onto the radiator, it will be the other gender to screw into the line.

Then all you need is for the one on the radiator to have a single hose barb, and the one on the line to have a single barb as well.

Once you have those, you will have 2 hose barbs that you can attach a hose to, then route that hose to the new cooler.

It ain't 🚀 science.
 
Has anyone put a aux cooler on their lesabre? If so how did you do it?
in front of the condensor or between the condensor and the radiator will be your best placement.
THe front offers the most room and easiest secure-method
The middle youre only method really to secure easily will be to use the zip tie things to push through the fins, , but it would be a little work to get hoses or pipes routed in there nicely and without severe bends
 
This is the only one I could find to connect the male hardline to hose. It would require cutting and possibly flaring the existing line.
A 2000 lesabre will have thread in fittings on the radiator for the cooler lines, a 2004/5 radiator will have push in adapters.
There are checkballs ... somwhere... so do not cut the lines for sure.
The threaded portions can be pushed back, and then a hose clamp used to secure past the flare/ferrule in the trans cooler lines. , but thats to bypass. If you want to do both, listen to @DrivenDaily
 
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Looks like NPSF is the thread type

"NPSF (National Pipe Straight Fuel) threads are straight and designed to pair with male NPTF (National Pipe Taper Fuel) threads. This combo creates a seal through the interference fit between the threads, often eliminating the need for additional sealants. "
Im not sure if its exactly that at the radiator but it should be similar.. i think
 
When I replaced the radiator it had a fitting that looked like this in the photo pushed into the next photo on the intake and return
 

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When I replaced the radiator it had a fitting that looked like this in the photo pushed into the next photo on the intake and return
OH
Well FYI, those clips are 1 time use and the plastic collar to retain the clips are CRITICAL to put back on when removing pipes. im not sure if you knew that.

The radiator can be threaded into with either something else or with that, and a pipe retained, and then hoses doing the rest of the work or it can be in series yada yada depends on setup. have you put a aux cooler yet?

Remember unless you spend much time outside of florida, you would not hurt your car by putting the aux cooler after radiator , which means the outlet of the radiator goes into the aux, then the outlet of the aux goes to the transmission return

With the right SAE rated hose and fuel injection clamps, you can modify your original return hose pipe assmebly easily and as long as you mind the radius of your bends and keep hoses from rubbing things you can then use a simple flaring tool to put a flare on the pipes that are smooth, the others will have ferrules to use instead of a flare. the hose clamps would just be past the ferrule, id advise 2 clamps past any ferrule or flare to be safe (spaced apart, opposed directions would provide best security)


THis same modification method can be used to repair power steering return lines which just need new rubber and not new pipes, can be used to put a power steering cooler in the return circuit(adviseable in the future too), and can repair any transmission cooler lines with leaky crimps at the transitiion from pipe to hose or old hose sections)
 
OH
Well FYI, those clips are 1 time use and the plastic collar to retain the clips are CRITICAL to put back on when removing pipes. im not sure if you knew that.

The radiator can be threaded into with either something else or with that, and a pipe retained, and then hoses doing the rest of the work or it can be in series yada yada depends on setup. have you put a aux cooler yet?

Remember unless you spend much time outside of florida, you would not hurt your car by putting the aux cooler after radiator , which means the outlet of the radiator goes into the aux, then the outlet of the aux goes to the transmission return

With the right SAE rated hose and fuel injection clamps, you can modify your original return hose pipe assmebly easily and as long as you mind the radius of your bends and keep hoses from rubbing things you can then use a simple flaring tool to put a flare on the pipes that are smooth, the others will have ferrules to use instead of a flare. the hose clamps would just be past the ferrule, id advise 2 clamps past any ferrule or flare to be safe (spaced apart, opposed directions would provide best security)


THis same modification method can be used to repair power steering return lines which just need new rubber and not new pipes, can be used to put a power steering cooler in the return circuit(adviseable in the future too), and can repair any transmission cooler lines with leaky crimps at the transitiion from pipe to hose or old hose sections)
What should I do? Just cut the hose section of the return line and plumb a line to and from the cooler? Or should I use the stock fitting and not cut anything?
 
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What should I do? Just cut the hose section of the return line and plumb a line to and from the cooler? Or should I use the stock fitting and not cut anything?
on the return line, youd want to cut off the line where it goes from hard pipe to hose , if its at a good angle/position for you to put a hose on that. you can put it anywhere you want personally. a picture of the area in front of your radiator by your subframe from above would help me advise you

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Im guessing your lesabre doesnt match the park avenue like shown here 100% , maybe it does, but this kinda picture just showing the lines in full (so 2 pics likely, to capture the lines as they come out of the radiator) and the ones engine side. also note im talking about the upper part of this photo, the bottom is the return line for hte power steering which is 100% not the same as yours (since this is a pre-tsb return line , the tsb one would probably match yours)
 
I can snap a pic tomorrow of the area. I have the splash shield off right now so I can get a good pic from underneath the car.
This is what my lines look like from above and also below
 

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This is what my lines look like from above and also below
where about you want to puyt the cooler you think do you have one ?
 
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