Transmission fluid leaking from lower trans. cooling line @ radiator

vincentvaldez · #1 08-01-2006, 12:40 PM

Hey all, first post but I've appreciated the info and help you've provided on a bunch of other things.

Had to replace my radiator. Replaced it and all appeared fine. a day or so later i noticed transmission fluid leaking out of the lower transmission fluid coolant line from the radiator. It is leaking between the metal flange and the pipe at the compression fitting. I've tried to reseat the fitting, but it still slowly drips out between the pipe and the fitting. It was difficult to get the pipe in, but appears fully seated, the top transmission coolant line does not appear to be leaking. anyone have any experience or tips on how I can get this darn thing to stop dripping tranny fluid all over or seat the pipe better in the fitting? It doesn't seem like the spring clip on the fittings is holding it tight enough to prevent the leaking.

I'd appreciate any help. this 100 degree whether is killing me trying to get this thing fixed. Thanks.

vincentvaldez · #2 08-01-2006, 12:48 PM

i should probably add it's a 2000 4x4.. sorry

AJT1961 · #3 08-01-2006, 04:25 PM

It's a basic single-flared metal line/compression fitting set-up. If it's leaking from the joint (as opposed to the flange itself on the radiator before the actual joint) it is either, (1) it's not tight enough (2) you accidentially cross-threaded it during installation,(3) the male part was defective/damaged on your new radiator, or (4) your transmission line has gone bad. Without seeing it up close, it's hard to guess which. If tightening didn't work, I'd take it off and closely inspect the threads and the mating surfaces to see if there is any visible damage.

muddog321 · #4 08-01-2006, 05:11 PM

Just did a 98 radiator and exact same design with the C clip fittings. There is no compression fitting as such - the base screws into the plastic rad housing and then the pipe inserts and is held in by a C clip so make sure the metal line is fully inserted and the clip fully engaged - then a plastic holder snaps over the C clip to hold all together. Hope the O ring in there was not mangled or it could leak - guess GM is only place to get it - can't remember if the O ring was in the fitting or on the pipe (think on the pipe) so feel/look at it. The new C clips were not the same so I used the old ones and that may be your problem - sorry on the heat its the same eveywhere now!

AJT1961 · #5 08-01-2006, 05:30 PM

Interesting. I did my 2000 4X4 radiator about a month ago and it doesn't have that kind of C-clip set up at all. Oh well, good luck and nevermind what I said then.

RJ MALIBU · #6 08-01-2006, 06:43 PM

Had the same prob on my 97. Try putting some teflon tape between both fittings . Its the only way to stop it from leaking.

vincentvaldez · #7 08-02-2006, 08:33 AM

thanks everyone for the info.

Yeah, it wasn't leaking at the threaded connector but the push in connector with the c-clip spring fittings. I used the new fitting that came w/ the radiator. Maybe I'll try to pull the new one off and put the old one in there if i check and the pipe is pushed in as far as it goes. They appeared to be the same to me, but could be slightly different.

There is a small O-ring inside the fitting, nothing on the pipe but a chamfered / tapered end. possibly i do not have the pipe inserted enough or the clip does not hold it tight enough against the o-ring. guess trial and error will finally solve this one.

thanks for all the responses.

vincentvaldez · #8 08-02-2006, 08:35 AM

AJT - The oil cooler lines didn't have the c-clip, only the transmission cooler lines

muddog321 · #9 08-02-2006, 12:24 PM

I did oil lines on 98, 99, 01 and all had the same C clips so I am confused.
Maybe GM used whatever was cheapest that month!

AJT1961 · #10 08-02-2006, 02:07 PM

Although I do think I am getting prematurely senile from too many years of hard partying, for the life of me I don't remember anything like what you guys are describing on the tranny lines -- and I know I didn't have to remove or install any C-clips. Once it cools down around here, I'm going to have to out to take a look -- if only for my own mental health. If I find a C-clip, I'm seriously making an appointment with a neurologist.

silicon212 · #11 08-02-2006, 02:15 PM

Quote:

Originally Posted by vincentvaldez

Hey all, first post but I've appreciated the info and help you've provided on a bunch of other things.

Had to replace my radiator. Replaced it and all appeared fine. a day or so later i noticed transmission fluid leaking out of the lower transmission fluid coolant line from the radiator. It is leaking between the metal flange and the pipe at the compression fitting. I've tried to reseat the fitting, but it still slowly drips out between the pipe and the fitting. It was difficult to get the pipe in, but appears fully seated, the top transmission coolant line does not appear to be leaking. anyone have any experience or tips on how I can get this darn thing to stop dripping tranny fluid all over or seat the pipe better in the fitting? It doesn't seem like the spring clip on the fittings is holding it tight enough to prevent the leaking.

I'd appreciate any help. this 100 degree whether is killing me trying to get this thing fixed. Thanks.

Does it appear to be cross-threaded? There's a possibility that the flare on the end of the tube is damaged or has a burr on it. Check this. If you find damage, you can get a replacement end piece - that with about a foot of power steering return line should get the leak fixed.

AJT1961 · #12 08-04-2006, 02:06 AM

Mystery solved. While working on my lawn tractor today (of course the drive belt had to snap today when it's sunny and 101 degrees) I came across a sealed plastic bag of "spare parts" that came with my new radiator. In it were four plumbing-type fittings with o-rings and little protruding plastic tubes and some kind of blue and red plastic tube grippers which apparently are used on some Blazers, but not mine. The directions said they were for vehicles with "quick connect" fittings which I don't have. At least I'm not senile -- yet. Anyone needing these "spare parts" I'd be happy to mail them.

vincentvaldez · #13 08-15-2006, 12:54 PM

Thanks for the help. Got it resolved. I took out the new fittings which were included with the radiator and put the ones back in with some thread sealant. I used the new c-clips that were included with the new fittings due to the fact that the old ones were stretched from being removed. Put it all together and no more leak.

Looking at the new fittings that came w/ the radiator, the o-ring inside the fitting barely protruded from the fitting. I don't know how they'd ever make a seal on anything. cheaply made.

Thanks for all the help... anyone else who changes it and has a leak may want to consider reusing the old ones, or at least inspect the new one's thoroughly before installing.

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