Pto?

[TacticalTruck]

I'm putting a swap loader on a M1078 and I need hydraulic power. Has anyone installed a PTO on the transmission of a non-winch truck?

 

[tobyS]

I'm not sure about the M1078, but I have PTO's that fit the "small" 6 bolt. They also seem to fit the M939, M35A3 and 916 with Allison. One picture I saw of the cover plate seems to be the same...but I don't have an M1078 to know for sure. Mine are mechanically engaged, not air.

I'm working on a direct mount pump but not done yet (and have no idea if you have room).

 

[Suprman]

The pto is easily swapped. I have removed them for installation on other trucks. Truck must be in neutral to engage. All transmissions have the ring gear already installed. Pto is electrically solenoid activated. First gen trucks use hand throttle up, A1 trucks get a signal to the engine computer to kick up the rpms.

 

[TacticalTruck]

Thanks guys. I figured the original surplus ones would bolt up but I haven't found any for sale. The -24P only shows the pump and not the PTO to find a part number. The bolt pattern is different from M939 series. It's 8 bolt and there's plenty of room. I was hoping some one had a Muncie part number or information towards a civi equivalent.

 

[Suprman]

Heres pic

 

[tobyS]

Heres pic
View attachment 641751

Good shi+ man! That's an entire wet kit with some reasonable tank capacity.

 

[Suprman]

MD3070PT is a 3000 series trans. Search allison 3000 series pto a few different things come up. I would check with allison have your trans serial number on hand to verify compatibility though.

 

[TacticalTruck]

I've got the Chelsea PTO mounted and I'm trying to wire it up. The Chelsea diagram shows a wire connected to the TCM which tells the transmission when it is engaged. Chelsea tells me I actually don't need this on the older transmission. I know the original PTOs will only engage in neutral and I've found the controlling relay in the wire diagram but it has two wires going to the TCM and I don't know if the 12 volt signal will even work on the 24 volt TCM. Ant Allison people out there that can give me guidance?

 

[scottmandu]

MD3070PT is a 3000 series trans. Search allison 3000 series pto a few different things come up. I would check with allison have your trans serial number on hand to verify compatibility though.

Allison lists a couple different drive gears for the 3000 series PTO..

 

[scottmandu]

I've got the Chelsea PTO mounted and I'm trying to wire it up. The Chelsea diagram shows a wire connected to the TCM which tells the transmission when it is engaged. Chelsea tells me I actually don't need this on the older transmission. I know the original PTOs will only engage in neutral and I've found the controlling relay in the wire diagram but it has two wires going to the TCM and I don't know if the 12 volt signal will even work on the 24 volt TCM. Ant Allison people out there that can give me guidance?

Transmission won't go out of 'N' with the PTO engaged and the PTO won't engage unless the Transmission is in 'N'

 

[Oxyacetylene]

Transmission won't go out of 'N' with the PTO engaged and the PTO won't engage unless the Transmission is in 'N'

Is this just how the transmission controller is programmed? The FMTV wrecker I thought had an override for this so you can engage the PTO for winch while the transmission is engaged?

 

[tobyS]

I doubt that it's much more sophisticated than an open-close switch. Where one position it's open and breaks the circuit and one position closed and makes the circuit. Do you have a continuity tester?

 

[TacticalTruck]

I spoke w/ Chelsea, and he said I could ignore it. So I did and it works fine.
The original military set up adds another relay to the power panel that communicates with the transmission.