buddy of mine just picked up an 89 crew cab duallie f 350 2wd with a 460, c6 and a gear vendors under/overdrive. when he bought it the po said he just had the trannie rebuilt but didn't want to spend the 500 to have the electronics reinstalled.

at the moment it has the wires hooked up at the tailshaft end and a "unit" mounted to the dash.

my questions are


#1 what needs to be "plugged in"?
#2 where can i find a wiring diagram?(haven't looked at the wiring situation yet)
#3 any thing i should know?



discuss............

 

There are two methods of wiring a GV unit - one with a controller and one without.

Without is easy - apply 12V to engage the unit, remove 12V to disengage the unit. Couldn't be any easier.

However... you should not engage the unit at lower speeds because there's not enough driveshaft speed to allow the internal hydraulic pump to produce any pressure, and in turn the clutch won't "bite" and instead glaze over fairly quickly. Also, the hydraulic pump generates ZERO pressure in reverse, so engaging it while going backwards and that's no good either.

That's what the control box is for - it prevents the unit from being engaged under these circumstances to avoid damage.

The white wires are for the solenoid, no attention to polarity necessary.
The yellow wires are for the signal generator, again, no attention to polarity necessary.
The red wires go to the on/off switch in the truck for operator control, and it's color coded so that the light inside the switch illuminates when the switch is closed and the control box powered.
The black wires engage/disengage the GV unit and illuminates a light in the switch when the GV unit is in overdrive.
The red wire connects to 12V and the black wire to ground, and put a 5A fuse in series with the red wire unless you insert an additional fuse in your fuse box and connect the red wire to that fuse.
The GV unit provides a speed signal to the controller box so it's compatible with any vehicle regardless of how the vehicle knows and displays how fast it's going. The GV unit is only interested in driveshaft speed anyway as it's inserted into the driveline and generates it's pump pressure off that.

You can get more information or maybe a PDF for the wiring diagram at Gear Vendors under/overdrive transmissions the most awarded auxiliary transmissions.. They're a pretty good company and I happen to really like their units.