Tighten or replace trans cooler line fitting at radiator
 

The top transmission cooler line leaks at the screw in fitting on the radiator. Have to get radiator hot (about 5/8 on gauge) and can see steam coming from around the fitting threads. Cannot tell the exact location of leak.

Looks like there is a square fitting on the radiator where the threaded fitting screws. It may also be leaking between the metal pipe and the fittings. Could not tell exactly.

When use wrench on fitting, plan to also use wrench on square fitting. May save the radiator. Also will be using lube fluid on threads.

Question is if cannot use wrench on square fitting, will radiator stand tightening fitting? Or removal of fitting?

I'm not sure but THINK the hose has an O-ring on the end of it. Maybe it's no good and causing the leak. Or maybe the flare has a crack in it. I'd just try tightening it first, but don't crank the hell out of it. You can bust the flare for sure if you over torque it.

Sorry to say it is probably radiator time. As inexpensive new radiators are now no radiator shops fix this type of problem. Rube is right there is an o-ring that has failed, the problem is the plastic tank and the one time use aluminum retaining tabs.

Thanks Rubehayseed and 02 LW300. That O-ring was excellent.:)

Had not expected an O-ring. Oil and filter needs to be changed so put front tires on cinder blocks in order to get under. In case you are wondering, bottom of front tires about even with rear. It’s setting on slope. After change oil and filter, start on leak.

When first looked at leaking fitting, looked like a flair fitting. Do not recall seeing any tabs on square fitting on radiator. Originally planned on tightening or taking fitting off, cutting flair off, and re-flaring, then reinstall.

But an O-ring? New plan. Remove fitting and O-ring. Install new ring and reinstall fitting.

Have looked at Weather Channel. May be this weekend before do anything.

Keep up the advice. This was excellent advice as to O-ring.

Be sure to let us know if that takes care of the leak. I'm not usually that lucky! LOL