Transmission fluid leak (2004)

Hi guys.

I had originally posted this on the Gen 2 subforum, when I thought it was a power steering leak, but got no reply, so reposting here now that I've discovered it's actually trans fluid.

It's leaking from one of the metal pipes that go under the front end of the truck to the trans cooling radiator.

Check out the attached pic taken under the truck. The leak comes from the lower pipe at that black plastic bracket. I've put that paper towel upstream of the bracket to make sure that the leak isn't coming from higher up. It's not.



Now my first instinct is to cut off that plastic bracket and see what the heck is going on there (rust hole most likely) and see if I can temporarily patch it with epoxy putty.

Question for you guys: Is that really just a bracket meant to keep the two lines apart or does it actually connect the ends of each line and there's liquid flowing directly through the plastic?

Second question, since those pipes are rusty as hell (gotta love North East winters!) and expensive: couldn't I just cut off those metal lines above the rusty section and replace those metal lines with high pressure hoses instead? That way they'll never rust.
Is that a stupid idea?

Thanks!

Personally it looks like the plastic connector rubbed through the metal line with the rust and all. I would ditch the plastic connector and put a rubber sleeve over the metal lines in that area. Try to clean and spray the metal lines with rust converter and paint them to make them last longer. But thats my $0.02.

Do it the right way, replace both lines. If the one that is leaking is the pressure line the only way to seal it would be to weld it. Not worth the effort. Anything else is a waste of money.

I meant to do a write up on this a little while ago but been busy with work.

My leak started after I hit some deep water and ripped off the lower fan shroud which I'm sure jarred some other stuff around underneath but it was so bad it was bound to start leaking on its own soon.

Ironically the only purpose I saw for the black plastic piece was to keep the lines separated to maybe prevent them rubbing a hole I one another, but it also hold moisture pretty well too.

This is what's was under the black plastic piece.
I could smash it with my fingers it was so corroded.

One line leads from the drivers side of the radiator to the bottom of the radiator, the other goes from the drivers side of the radiator back to a distribution block kind of deal next to the trans on the passenger side. They are lines #2 and #3 on the diagram.

The rest of both the lines were in really good shape so after I talked to a parts guy at AutoZone I bought a couple lengths of 3/8" steel line, some compression fittings, a pipe cutter, rented their tubing bender and started cutting the old crap out.

To get the lines off of the rad you need a special tool and let me tell you I bought every tool that said it would work from multiple auto parts stores and returned every one. Luckily my neighbor is a mechanic at a Ford dealer and she brought me the right one, it's made by AST part #8021. Ebay has them for between $25-30.

After that it's just a matter of bending the tubing in the needed shape which is where I failed miserably, what should have taken about 2' of tubing all together took me about 5'. A wire coat hanger as a template would have really came in handy at that point in the repair.....hind sight.

After that I tightened all the compression fittings and replaced the 3 quarts of trans fluid that had leaked out over night, it was so low that it wouldn't move at all.

That was a month and about 1000 miles ago and it hasn't leaked so much as a drop. Total cost had I not screwed up so much of the tubing would've been about $30. $60ish if I would've had to buy the line tool.

These pics are of all the repaired areas as of today.

Sorry I didn't do a write up sooner, hope this helps.

If you go the route I did make sure you rent the tubing bender if you don't own one. I asked the guy at AutoZone if you can bend it by hand like you can with brake line, which he said "oh yeah no problem it bends easily"..........no it doesn't. It kinks instantly, so I blame a few pieces of tubing on him lol.

Also I did NOT put the black plastic piece back on lol.

Great post! Thanks for sharing. I will be inspecting these lines this weekend.

Guys, thank you all so much for the advice. This is great! Thanks for the detailed writeup Mike.
Does a lot of trans oil pour out when you disconnect the lines? I've noticed that mine stops dripping when I stop the engine, so I imagine that when the engine stops the oil settles down somewhere lower than these lines, right?

So you guys think that rubber lines won't do? I saw that online auto parts stores sell reinforced rubber lines specially designed for transmission fluid. They claim to withstand 400 PSI and 300 degrees. I'm just thinking that those would be easier to install than having to bend metal lines and that they'd be rustproof. Mike, are your new lines copper or other rust resistant metal?

bertro said:

Guys, thank you all so much for the advice. This is great! Thanks for the detailed writeup Mike.
Does a lot of trans oil pour out when you disconnect the lines? I've noticed that mine stops dripping when I stop the engine, so I imagine that when the engine stops the oil settles down somewhere lower than these lines, right?

So you guys think that rubber lines won't do? I saw that online auto parts stores sell reinforced rubber lines specially designed for transmission fluid. They claim to withstand 400 PSI and 300 degrees. I'm just thinking that those would be easier to install than having to bend metal lines and that they'd be rustproof. Mike, are your new lines copper or other rust resistant metal?

Click to expand...

I didn't lose too much when I disconnected the lines but I started my repair the day after the damage to the lines happened so between sitting over night and limping my truck back home I lost about 3 quarts. You'd definitely need a drain pan.

The guy I talked to at AutoZone said the rubber hose should work but I didn't want to chance it and at the life cost of the parts i needed for the repair I couldn't complain.

Here's the exact line I used, not bad @ $7.99 for 5 ft.

And the compression union fittings.

The only other expenses I had was a tubing cutter $6.99, trans fluid about $20, and the $20 deposit for the tubing bender which I got back when I returned it. All of which I got at AutoZone.