Transmission Cooling Line Repair?

[EddieC]

2008 Tahoe: My upper transmission cooling tubing is leaking at the crimped upper connection of the short (flexible?) section with crimped connectors in the rear of the engine compartment. I question flexible because it is the short intermediate section inside what appears like a black wiring harness protector. I don't know but suspect there may be a rubber hose inside.

I previously added a hose clamp that I thought was going to be the ticket but is weeping a bit.

It appears that it would be tough to replace the entire tube from radiator to transmission because of the tough to reach fitting on the top of the transmission so the question is has anyone successfully fitted in a replacement for the flexible section and, if so, what recommendations can be shared?

Is there much pressure in that line that would require special consideration?

 

[blackelky]

Both of the lines from rockauto ac delco brand are 80$. Not a terrible job to do either

 

[EddieC]

Both of the lines from rockauto ac delco brand are 80$. Not a terrible job to do either

I'm not so concerned about the price as much as not seeing how to reach the fittings atop the tranny

 

[gooffeyguy]

When I installed a remote external trans filter I ended up cutting the hard tubes on each side of the rubber hose that's located between the front of the motor and radiator and used these TruCool 3/8 compression to 3/8 barb fittings and ran transmission hose. Also used spring style hose clamps because worm style hose clamps would cause seeping during the winter and need tightening.

 

[EddieC]

When I installed a remote external trans filter I ended up cutting the hard tubes on each side of the rubber hose that's located between the front of the motor and radiator and used these TruCool 3/8 compression to 3/8 barb fittings and ran transmission hose. Also used spring style hose clamps because worm style hose clamps would cause seeping during the winter and need tightening.

View attachment 421206

I like that! I imagine that the lines have to be pretty new/clean for the compression fittings though, right?
Mine are original from '08.

 

[gooffeyguy]

I used a tubing cutter, like used to cut copper and aluminum pipe, to cut the lines and debur the ends.

The trans lines aren't under a lot of pressure, like 30-50psi.

Derale makes these fittings also

Universal 3/8" Transmission Cooler Line to 3/8" Hose Barb Compression Fitting

Universal 3/8" Transmission Cooler Line to 3/8" Hose Barb Compression Fitting Cooling Line Radiator Adapter Fittings 3/8" Compression Fitting Kit 13032

derale.com

 

[donjetman]

I replace my cooler lines (rpo code KNP) in 2018
25999420 (2 lines in one), and 15779543.
I did it while doing the oil pump pickup tube o-ring job, etc.

 

[EddieC]

I used a tubing cutter, like used to cut copper and aluminum pipe, to cut the lines and debur the ends.

The trans lines aren't under a lot of pressure, like 30-50psi.

Derale makes these fittings also

Universal 3/8" Transmission Cooler Line to 3/8" Hose Barb Compression Fitting

Universal 3/8" Transmission Cooler Line to 3/8" Hose Barb Compression Fitting Cooling Line Radiator Adapter Fittings 3/8" Compression Fitting Kit 13032

derale.com

Is using fuel line ok?
Derale oil line price is not reasonable.

 

[gooffeyguy]

Is using fuel line ok?
Derale oil line price is not reasonable.

Don't know, I've never used fuel line for trans fluid, but I'd like to think that there is some reason they make trans line. Maybe more heat resistant. Trans fluid gets pretty hot while fuel doesn't.

 

[blackelky]

I'm not so concerned about the price as much as not seeing how to reach the fittings atop the tranny

is that a 4l60e? The 6l80 are on the side of the trans