Very small transmission leak.

Hey all,
So following the excellent instructions offered here I did a drain and fill on my '23 6 A/T about 3 weeks ago. It went well but last Friday when I installed my skid plate I noticed a single drop of ATF on the check fill plug and a little dampness on the pan. I wasn't sure if I had just forgotten to wipe everything down so I cleaned it up and started monitoring. As of last night the drop is back. I was wondering if someone could offer up what I might have done wrong? I did double check torque the wrench did indeed click at 15 ft/lbs. Thank you in advance!

 

Did you forget the crush washer?

If it's just a slight drip, I'd just degrease the plug and the skid below it and check again in a week and see if its still dripping

 

I don't "think" I did unless it fell off and I wasn't paying attention during the temp check process. I honestly don't know. The drain plug is dry as a bone. Is it possible I installed the crush washer upside down? Worst case I will do the fill portion of a drain and fill and be damn sure the washer is there. It just bugs the shit outta me.

 

It sounds like you didn’t install a new crush washer you should have replaced it with a new one. Install a new crush washer and then recheck.

 

That’s fair! It is very possible that on the second drain and fill I did manage to forget. I was getting frustrated with chasing the temp check and no fluid coming out of the fill check tube and I may have completely forgotten… Gonna fix it in the morning! Pretty sure I have nine or 10 of those crush washers laying around.

 

Had a small oil leak that was so small I never saw any drops nor noticed a difference on the dip stick first few days and next week after oil change. Obviously continuous checks would have alerted me.

But it was indeed the crush washer. Not sure if the trans ones are the same, but the small "film" that's on the ends of the oil crush washers had delaminated a bit causing a small leak.

 

No crush washer is no big deal (furtive look sideways), I forgot mine on my manual trans fluid change. Still sitting on one of my toolboxes 27k later.

I've never replaced a crush washer either. YMMV, don't listen to me, don't do as I do. I've always just cleaned them and the mating surfaces thoroughly, and tightened things up and then given a single whack with my copper hammer, then just a smidge extra. Hell, my current tacomas engine oil crush washer has been stuck to the oil pan since new. I just clean it and the mating surface of the oil drain plug off and way she goes.

 

Note to OP:
Have the vehicle cold and running when you remove your check plug and you might not have to do any cleanup as the fluid level will be low.

 

Got it sorted this morning. Got the truck level, added a quart of WS ATF, and did the fill portion of the drain and fill. Got about a quart out so, as expected, a very small leak. Also as expected, no crush washer to be found. Fuck, I'm an idiot. All is well now and my mind is at peace. Now hunting a replacement fill plug (It's got some VERY light rounding but if it is less than $5.00 its worth having a fresh one on hand for the next time), o-ring for the fill plug, and a handful of crush washers. Thanks for all the of the advice guys! I'll figure this all out eventually!