Disconnected Transmission Cooler Line

2002 Yukon XL · November 12, 2013

I have a 2002 Yukon XL 1500. Last night, coming home from work, I noticed the truck having difficulty changing gears just within a few hundred yards of home; I didn't think much of it and went in the house. This morning on the way to work, I had the same difficulty until the truck stopped completely and would not move. This evening after work (I took my son's car to work), I noticed the entire right (passinger) side of the engine compartment sprayed down with ATF. I finally found the culprit: the line coming from the transmission between the right headlight and the radiator was disconnected.

The area is very cramped and lighting was an issue so I am not sure what I think I see is actually what is there. The knobbed end of the steel tube was exposed and there was some sort of plastic piece was behind it. I assumed that the plastic piece was a nut of some sort, but it did seem to have threads. I tried repeatedly to thread the plastic piece and repeatedly failed.

Questions:

1) What is the best way to expose the area so there is some room to work in? I can barely reach the area after removing the plastic cowl covering the radiator.

2) Is there threads on the plastic piece or how is the steel tube connected to the radiator?

3) How much ATF does the transmission hold?

4) I noticed ATF cooling lines advertised; does the fact that it seperated indicate a need for replacement and how difficult is that?

scooby5121 · November 13, 2013

Hopefully you did not burn your transmission.

You first would need to buy a new line for about 230.00 Cdn. dollars

Good Luck

txab · November 13, 2013

You should have this style fittings

See if the clip is still in place in the fitting. I'd pick up a new clip no matter what. You can put the clip on and insert the cooling line until it snaps in place or put the cooling line in and then put the clip on. The plastic piece you see is supposed to be somewhat of a retainer ring for the clip.

Transmission holds about 12 qts when empty. You should need at least 5 or 6 to refill. You can buy more than you need and take it back

2002 Yukon XL · November 13, 2013

Thanks txab! What I thought was a plastic piece is probably just the top to the nut shown above. Since the piece won't slide off the tubing, I assume the retaining ring is still there.

Thanks again!

Chris · November 13, 2013

Think the plastic has to move first. But, it has been a while and all my lines including those stock fittings have been swapped to -6 AN

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txab · November 13, 2013

Thanks txab! What I thought was a plastic piece is probably just the top to the nut shown above. Since the piece won't slide off the tubing, I assume the retaining ring is still there.

Thanks again!

2002 Yukon XL · November 29, 2013

Don't know how they got the camera in there to take the picture, but that was it... then. The plastic cap apparently helps keep the snap ring in place and the snap ring was missing. The fitting was about 50% wider through the fluid path due to wear than the new part, so it was for the best to replace the whole thing.

I got the part and installed it, then filled the transmission with ATF and tested the truck in my driveway; it moved in reverse and forward, I thought I was done. The next day, I got in it to go to town and the truck would not shift out of first gear. I tried manually shifting through the low gear sittings but still would not shift. I also tried driving down backroads (don't want to go above 30mph as that is 4000rpm) to see if it was something that was frozen and just needed to loosen up; still nothing. Been busy and so I haven't gotten back here (to this forum) until today but I thought the transmission was destroyed and there wasn't much point. Then someone at work said that the fact that the truck would move was promising and if the transmission was truely shot, it wouldn't move at all.

Is there anything that can be done in a driveway with scant tools that might help?