Simp's M915A1 and M920 Build Thread
Picked up an 1984 M915A1 off of GSA for $3,156.00. Listed as a non runner. Truck was used at the Oklahoma State University Ranch site so basically it hauled cows. They said it had not been started in 4 or 5 years. 140,300 miles on the ODO. Rebuilt as RSMS at RRAD in 2006. Originally was tan, they went with white.
Dropped 2 small group 24 batteries in her on a 40 degree morning and she fired off on the 2nd spin. Typical 915A1 pretty much. Not much noticed to be wrong with it at first except for the junky 11R22.5 tires. Nice shaking ride home the 533 miles. Noticed on the drive home that the heater blower isn't working and that the headlight switch gets hot which is typical. Other than that. Not much else.
Truck is equipped with dual air civi air ride seats that are pretty nice. VisionAire LLC air conditioning system. It has a pretty powerful blower but it does not have any temperature adjustment which is weird to say the least. AC does work though at least. Truck also has a single pole trailer charge wire which is a nice feature for if you have a winch on the trailer to charge the batteries. They also made their own battery box top out of some 1/4" steel plate it is nice and heavy.
Project build list:
- Paint to Night Mission green: Done 10/13/19
- Install rear winch platform from a 916/920 - Planning on Installing the light 20k winch from the front of a 5ton with a Yanmar L70 diesel motor to run the pump, Since the PTO's are really a pain to add on the 915s. This will be used to winch onto the lowboy trailer it will be hauling. Not near as heavy and as much crap as the normal 45k winch so it should not add much front axle weight.
- Front Axle air brags - cut down the bump stop on the front springs and add an air bag for better ride.
- Dual Fuel Line - Done 10/13/19
- Hi Flow Injectors - More umph.
- HT4B turbocharger - More umph.
- Possible 13 spd swap - Have the clutch setup, flywheel, bellhousing and RTO16713 that came from behind a Big cam. With that setup it would pretty well run high speed at low rpms.
- 11R24s on the rear and 395s up front to run while the Allison is still in it. If i do the 13spd swap I will run 315/80/22.5s that the M916A3s run
- Add a 55gal tank from a 931 - Truck has a side frame rail mounted toolbox between the exhaust pipe and the fender. replace it with the 55gal tank to increase range with a transfer pump to pump into the main tank
- Add a pyro, boost, dual digital voltage gauge.
- Swap Alternator for a Cummins/Delco Brushless 100amp 24v unit.
- Install Bussman 100amp interverter to power the 12v side using the single voltage alternator.
- Install LED tail, turns, and headlights will probably be JW Speakers - swapping to this should limit the heat problem on the headlight switch
- cummins 8D batteries.
Will update as progress goes forward.
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Picked up an 1984 M915A1 off of GSA for $3,156.00. Listed as a non runner. Truck was used at the Oklahoma State University Ranch site so basically it hauled cows. They said it had not been started in 4 or 5 years. 140,300 miles on the ODO. Rebuilt as RSMS at RRAD in 2006. Originally was tan, they went with white.
Dropped 2 small group 24 batteries in her on a 40 degree morning and she fired off on the 2nd spin. Typical 915A1 pretty much. Not much noticed to be wrong with it at first except for the junky 11R22.5 tires. Nice shaking ride home the 533 miles. Noticed on the drive home that the heater blower isn't working and that the headlight switch gets hot which is typical. Other than that. Not much else.
Truck is equipped with dual air civi air ride seats that are pretty nice. VisionAire LLC air conditioning system. It has a pretty powerful blower but it does not have any temperature adjustment which is weird to say the least. AC does work though at least. Truck also has a single pole trailer charge wire which is a nice feature for if you have a winch on the trailer to charge the batteries. They also made their own battery box top out of some 1/4" steel plate it is nice and heavy.
Project build list:
- Paint to Night Mission green: Done 10/13/19
- Install rear winch platform from a 916/920 - Planning on Installing the light 20k winch from the front of a 5ton with a Yanmar L70 diesel motor to run the pump, Since the PTO's are really a pain to add on the 915s. This will be used to winch onto the lowboy trailer it will be hauling. Not near as heavy and as much crap as the normal 45k winch so it should not add much front axle weight.
- Front Axle air brags - cut down the bump stop on the front springs and add an air bag for better ride.
- Dual Fuel Line - Done 10/13/19
- Hi Flow Injectors - More umph.
- HT4B turbocharger - More umph.
- Possible 13 spd swap - Have the clutch setup, flywheel, bellhousing and RTO16713 that came from behind a Big cam. With that setup it would pretty well run high speed at low rpms.
- 11R24s on the rear and 395s up front to run while the Allison is still in it. If i do the 13spd swap I will run 315/80/22.5s that the M916A3s run
- Add a 55gal tank from a 931 - Truck has a side frame rail mounted toolbox between the exhaust pipe and the fender. replace it with the 55gal tank to increase range with a transfer pump to pump into the main tank
- Add a pyro, boost, dual digital voltage gauge.
- Swap Alternator for a Cummins/Delco Brushless 100amp 24v unit.
- Install Bussman 100amp interverter to power the 12v side using the single voltage alternator.
- Install LED tail, turns, and headlights will probably be JW Speakers - swapping to this should limit the heat problem on the headlight switch
- cummins 8D batteries.
Will update as progress goes forward.
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