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Tranmission fluild leak

1147 Views 23 Replies 7 Participants Last post by  plplplpl
I'm trying to identify this slow leak of what seems to be AT fluid.
The area around this hose on the driver side seems to be the culprit but I didn't think there was any transmission fluid lines going to the front radiator area. This is a 2003 Pilot.
It's the smaller hose on the right.

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appreciate the response. Trying to find the part number for that hose and I can't seem to find it.

The transmission has some slippage which went away with drain and fills for about 1 year, now it came back - but suspect it's due to low fluid.
I'm about to do the transmission filter, but will probably hold off on radiator as it's a back up car and trying to not put too much into it unless necessary.

part 15? - when i look online it's a straight hose, whereas the one on the car seems molded.
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I'll take a look for sure but it is a backup car and has been a lifetime AZ car, so rust is less of a concern.
I got the part above, but it definitely is not the right part.
It's possible I'm understanding it wrong but the above diagram, seems they switched part 13 and 15.
I ordered part 15 and got a short straight tube. When looking at the car, part 13 is a straight short tube that connects to the piping that goes across the radiator.
I ended up ordering part 13 - 25212-PGK-010 as well now and will wait to replace once I get it.

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Any chance they sent you #14?

Another failure point is the pipe joint/nipple into the radiator, seen a case where it popped out of the radiator, losing all transmission fluid, happened probably due to dissimilar metals (galvanic) used between that joint and radiator. In that case, you have to change radiator.
Possible, though it looks exactly like part 13 when looking from the bottom. The part number does match all sources I checked - so it's either a part numbering error or - more likely - I'm a dumb dumb somewhere about this.
So I found the leak, it looks like it’s at this connection at the radiator. Anyone know if I can tighten this down or if this nipple would come with a new radiator?
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New radiator come with improved nip connections. Could try to tighten it down a bit but rule out the drip may be from the rubber hose connection.
seems I can no longer avoid doing the radiator. Hoses, thermostat, cap and radiator is typically what’s done all at once right?
Do I need to drain the transmission since I’ll be disconnecting these?
I’d definitely give that hose a second look. It doesn’t appear to be seated properly and the clamp doesn’t appear to have been moved at some time. If you look closely I added two red arrows to your photo.

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I tried to seat it better and can keep trying but based on the photo, it’s coming from the nipple connection rather than the hose. I already ordered the denso radiator :)
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