Do I have Transmisson Leak?

[hakanerdogan]

Hi everyone,

This morning I detected a red fluid on the ground before I start driving. Then I checked the transmission fluid level while engine was running, engaged to P position. And the control stick was complete dry. But when I stop the vehicle and check it again, I see fluid level is OK. But according to manuel it says check it when engine is running so I am sure that I still have fluid in it but inadequate.

And I took a picture of leaking point so you may help me to follow a solution If it is a common problem.

1997 Pathfinder, 136.000 miles, 4x4 Automatic

https://imageshack.com/i/pndfZHiZj

Thank you all.

[atraudes]

That's kind of an odd place to be leaking transmission fluid, but I suppose it's not impossible. Normally when oil is coming out of that weep hole it's motor oil because the rear main seal is leaking.

I'd check around the sides and top to see if there are any lines running into the transmission that could be the leak points.

[hakanerdogan]

That's kind of an odd place to be leaking transmission fluid, but I suppose it's not impossible. Normally when oil is coming out of that weep hole it's motor oil because the rear main seal is leaking.

I'd check around the sides and top to see if there are any lines running into the transmission that could be the leak points.

Well first I thought its from rear crankshaft seal which is no big problem but the fluid is very very bright-clean red unlike engine oil. Then I started to suspect from transmission fluid. I will get a sample from engine oil then check again.

Thanks for the post!

[Hawairish]

Could be the seals or o-rings for the front of the transmission, as part of the oil pump ("transmission oil pump", that is).

[hakanerdogan]

Could be the seals or o-rings for the front of the transmission, as part of the oil pump ("transmission oil pump", that is).

Didn't know that the transmission oil pump located there. Sounds like the transmission will be removed...

Thanks for that information.

[Hawairish]

Yep, take a look at AT-137 ("oil pump housing seal" towards the top) and AT-153 for the oil pump breakdown (seal on far left side): http://www.nicoclub.com/manuals/Pathfin ... der/at.pdf

My guess is that the leak would originate from the seal around the input shaft shown in the pic:


The pump housing is basically the input shaft cover, and this seal fits between it and the torque converter. RockAuto has it listed as both "Fluid Pump Seal" and "Torque Converter Seal" for that reason.

Here's a full breakdown of the transmission, see part "070": http://at-manuals.com/wp-content/upload ... G4RO1A.pdf

If you change that, probably a perfect time to change the rear main seal, too.

[hakanerdogan]

Yep, take a look at AT-137 ("oil pump housing seal" towards the top) and AT-153 for the oil pump breakdown (seal on far left side): http://www.nicoclub.com/manuals/Pathfin ... der/at.pdf

My guess is that the leak would originate from the seal around the input shaft shown in the pic:


The pump housing is basically the input shaft cover, and this seal fits between it and the torque converter. RockAuto has it listed as both "Fluid Pump Seal" and "Torque Converter Seal" for that reason.

Here's a full breakdown of the transmission, see part "070": http://at-manuals.com/wp-content/upload ... G4RO1A.pdf

If you change that, probably a perfect time to change the rear main seal, too.

Perfect timing, you've just posted while I was downloading all contents and looking for that. Thank you so much.

[Hawairish]

No problem, and good luck.

[hakanerdogan]

Before taking the transmission down, some mechanic adviced me to use an ATF additive, which is to stop transmission leaks. (Liqui Moly ATF Additive) And I changed the fluid (not complete flush) with Mobil ATF Dexron III.

Let's see whats gonna happen...

[Hawairish]

Yes, worth a shot. Just be sure to degrease the area and wipe clean to confirm that the leak has stopped. May have to watch it closely, since there might be some remnant fluid that still needs to clear from the weep hole.