4 spd to TH400

[LS5]

Hey guys need some help with the kickdown wiring..I have a 1970 that was originally a 454 m-21 4spd car,but somewhere not too long ago it was changed to a TH400 and the kickdown wiring has the typical 2 pin plug boot that goes onto the side of the tranny which was probably fine for the 4 spd.But the TH400 only has a provision for a single pin plug. The orange would be the power it needs to activate it I would assume.?? But what do I do about the Black wire????? Does it need to be looped to the orange or grounded out somewhere.???? any input would help......

PS. The car will not stay an auto for long as it will go back to a 4spd again once all the stuff is found so this is a temp fix in order to get the TH400 working fully....Darren.

[monte70car]

Darren the black wire should be a ground me think. We have that same type of 400 in our Elkie and I just ran one orange wire to the kick down switch. Leaving the black wire unhooked should be ok but if you want to feel safe make up a ground with a eyelit on one end and a male connection on the other and you should be good.

[Mike 57]

The orange wire is the kick down the black wire is TCS I believe. My 72 had a two wire connector I just connected the orange.

[LS5]

Thanks Robert and Mike,I plugged in the orange for now and works fine...but cant help but wonder about the Black wire? maybe I need to ground it out on a bellhousing bolt in order to complete or close the loop.??? Darren.

[wallaby]

Somebody might know, or it might take some examination of the wiring schematic.

I don't know the answer....but I'm wondering now if the kickdown switch inside the car sends power down to the trans, or if it acts as a ground to complete the circuit?

[monte70car]

Mark the way the kickdown switch works is it gets its juice from the fuse panel and carries the juice down to the trans. Now if Darren Chevelle has the cowl induction flapper hood the kick down switch will also carry juice to the flapper door under the hood. When you get on the car the inner door on the hood opens at the same time as the outside door and the juice from the kickdown tells the trans to down shift from 3rd to 2nd.

[Monteman1971]

Darren...I think the guys are missing the big picture here.....Did you say an original 454, 4 speed 1970 Monte??????? Or are you talking about your Chevelle?

 

We have been looking for the fabled 4 speed, 454 Monte since the crack of time!!!!!

 

Pleeeeeease let us know.

 

As far as your issue....I think the fact is that the transmission is already grounded to the car, so the ground wire is not needed.

 

Steve

[LS5]

Yes Steve, I was talking about the Chevelle. I had no intent to get hopes up it just didnt dawn on me at the time to mention it.

I will ground out the Black wire anyhow just to close the loop and as the other guys mentioned that too. Yes there has been for years the thought of a LS-6 Monte somewhere maybe out there and Definatley in the Chevelle,But haveing an LS-5 4spd Chevelle SS there has got to be a LS-5 4spd Monte SS out there somewhere you would think?

[monte70car]

I know where Pete(former president) did a story with a guy who had a Dick Harrel(sp) monte. Darren I will check my 70 Chevelle wiring book out in the garagge but I'm pretty sure its a ground on the plug.