CUCV Neutral Switch?

[rdurh]

I'm still working on a diesel conversion on a 1979 GMC Jimmy using a 6.2L drive train out of a 1985 CUCV. The engine (6.2L J code), transmission (TH400) and transfer case (NP208) all came out of the same CUCV Blazer. I'm trying to finish up the wiring on this. The TH400 only has one wire (orange) coming out of the back of the transmission on the driver's side. There is no neutral safety switch. So I'm assuming that CUCV's didn't come with one. I'm also assuming that the orange wire is most likely the backup light switch, unless it is the neutral safety switch, in which case it isn't matching anything of the auto parts shelves to fit a TH400. I am also assuming that I can add a neutral safety switch, but to deeply into this yet.

[john8662]

IIRC the Neutral Safety Switch is in the Column in the truck in which the engine came from.

The orange wire is a mystery to me, although a TH400 I removed from a M1008 also has it.

Hopefully those in the know on this tranny will chime in. I only play with TH700's and 4L80E's and NV4500's.

J

[arveetek]

IIRC the Neutral Safety Switch is in the Column in the truck in which the engine came from.

The orange wire is a mystery to me, although a TH400 I removed from a M1008 also has it.

J

Yes, the neutral safety and backup switches are both located at the base of the steering column in the '73 to '87 style trucks. If the Jimmy had an automatic, you can use those switches already there.

The orange wire on the TH400 is probably the kick-down switch. The TH400's used behind the diesels had an electric kick-down with a switch mounted on the throttle pedal in the cab. When you mashed the pedal, the tranny would kick down into passing gear.

Casey

[rdurh]

Thanks. That makes more sense. I guess I need to find the switch for the cab to control the kick down.

The Jimmy did have a TH350 so I guess I'm lucky there just not as knowledgable about Chevy/GMC products as others.

[sidehackbob]

All TH 400s used electric kickdowns.

[john8662]

That explains it!

Thanks!

To control kickdown, you'll need the VRV for the injection pump that has the wires on it, not just the valve.

I had one somewhere.

J