1st gen Tranny question

[Stroked72Blazer]

I have a (Senser?) type plug just above where the dipstick goes in. It has two male spaid plugs on it. What the heck is it? Or has someone just swapped in a later model tranny with a lockup converter or something like that?

 

[4X4HIGH]

I believe that is part of a smog device that was used early on and it works in conjuction with an electric/vacuum solenoid and vacuum lines to the distributor.

 

[Blazer1970]

4X4HIGH is correct, it is a high gear indicator switch for the TCS (transmission controlled spark) system. It indicates that the tranny is in 3rd gear. I seldom see a truck that still has the TCS system intact, so you can likely just ignore it.

 

[Stroked72Blazer]

Cool Thanks. Does anyone know the thread size so I can just put a plug in it? Is it pipe thread or regular?

 

[4X4HIGH]

I haven't seen one in a long time but I believe it is 1/8" pipe.