I just replaced the speed sensor near the rear of the automatic tranny, and now it has a slight drip.

I assume that the little rubber o-ring (or gasket or whatyamacallit) is not seated correctly, or may be bad??? But I can't see anything crappy about it. I already threw the original one away with the bad sensor I replaced.

Where can I get a new o-ring.....Or do I need to do a form-a-gasket thing??or what?? I'd like to re-do this "once" and be done.
Anybody have an idea on this. I've never had a drip on my driveway in 20 years and this one is pissing me off.

if the 0-ring is cracked or something, shouldn't I be able to see it????

 

most of the time the o-rings tend to dry out and crack as you prolly already know, so just go the hardware store and find a new one.