This leak started one week after having a used transmission put in. On the transmission it states PLW on the left side, SLW right behind the rad fans.

To me this looks like a m/t fluid fill plug but doesn't look like all the DIY pictures I see. Car is a 2001 Civic EX w/ 133,000 miles. The "new" used tranny had less than 75,000 miles on it and feels fine.

What is this part?
Can I tighten it?
Does it have a seal?

Thanks!

 

Yeah, it's the fill plug. Threads should be coated. Try tightening it A LITTLE. If that doesn't solve it buy a new one. It's number 10: http://www.hondapartscheap.com/index...MISSION%20CASE

 

I found out its a sealing screw, but i guess it could be used for a fill plug also.

Tightened it 1/8 of a turn and no leak overnight!

 

that is NOT a fill plug!! that's a plug likely to access the snap ring for one of the shafts inside the trans.
a m/t fill plug has a 17mm head and an aluminum washer seal. so yes, you can tighten that. if it still leaks, you may have to remove it and put a bit of silicone sealant on the threads and re-install, there is also a torque spec for that which you may want to follow (steel plug in an aluminum housing)

 

My bad. That's what I used to put fluid in last time. Did go in pretty slow. Should have read my manual better. lol.

Torque spec is 18 ft-lbs.

 

Update, removed the sealing screw, applied Ultra Grey and everything appears fine. Thanks!

 

yeah thats where the snap ring is located, just did an isb on this tranny and i just put some ultra gray on it and no leak. good luck