I installed a glowshift trans temp sending unit into the test port on my 4l60e. I have it as tight as I comfortably can get it, and it still has a constant dribble of trans fluid leaking from it.

What kind of sealant can I use on this?

 

I need to get this running tonight without leaking anymore fluid, any help on what to pick up at napa

 

Maybe a white Teflon tape stuff?

 

All I had was pink, so I smeared some black rvt all over it. It worked for now..

 

It leaks because the threads are different. Teflon tape or liquid may help.

 

I use permatex high temp thread sealer, work great...

 

Yep, you're correct. I kept hearing they were the same 1/8 npt. But it sounds like the trans uses a different thread.

 

They are close, but they are straight threads vs the taper of a 1/8 npt.

Just don't over tighten and crack the case