1986 F-250 Lariat 12v Cummins 10 spd Eaton Fuller Road Ranger
1
0
Mods
1986 F-250 Lariat
Engine
1997 215 P7110 12 valve Cummins
Fully built from the ground up
all new seals and gaskets
Clevite performance H series main and rod bearings
billet oil squirters
ARP main studs
ARP rod bolts
ARP 625 head studs
polished and balanced crankshaft
Pistons bored .020 over
Mahle cast performance pistons. Early marine style big bowl 155 deg
Mahle rings and wrist pins
Billet freeze plugs
Keating machine billet front timing gear cover and tappet cover
Dual 12an breather lines with catch can
Deck was machined flat
Power Driven Diesel conical performance valve springs and chromoly retainers
Hamilton 178/208 camshaft
Hamilton 1.45" tappets
Hamilton extreme duty pushrods
Hamilton Cam bearing and bronze thrust plate
Resurfaced cylinder head
O-rings cut into the cylinder head
top hat style valve seals machined into the cylinder head
valve job
rocker arms machined for head studs
cummins .020 over head gasket
FASS 165gph fuel system
Bottom Sump installed on the fuel tank
All fuel lines upgraded to 1/2"
PDD AFC live
PDD 4000 rpm gov springs
5 x .016 PDD injectors
Torktek overflow valve
025 delivery valves
electronic fuel shutoff solenoid deleted. Cable system installed (more reliable)
DPS industrial style Fummins conversion exhaust manifold
BorgWarner S364SX-E Turbo. 64.5mm Compressor wheel Inducer Diameter. 68mm Turbine Wheel Outer Diameter
PDD performance air filter
Crazy Carls dual ram intake horn, billet intake plenum cover and grid heater delete
Sheid Diesel fuel lines
4" exhaust from the turbo to 5" stacks
PA Performance 200A 1 wire alternator
Transmission and Transfer Case
Transmission is an Eaton Fuller Road Ranger 10 speed RTO610. Completely rebuilt
1&3/4" input shaft
14" flywheel with a dual disc 1000 ft/lb rated pull style clutch. Manual adjusting type
SAE #2 bellhousing and starter
All hydraulics were removed from the truck for the clutch. I had to make a mechanical linkage with a bell crank on the frame to operate the clutch.
A substantial part of the floor had to be cutout to make room for the big transmission. I had to make a trans tunnel cover
A custom crossmember had to be fabricated to support the transmission
Onboard air is required to shift the ranges in the transmission so I decided to add air horns as well. The whole setup is from Hornblasters. Compressor, horns, wiring, and air line plumbing. The compressor can handle filling a tire and running small air tools
New shorter shift tower
The boot, valve, and shift knob came out of a Freightliner Cascadia
The transfer case is a divorced NP205 unit
Transfer case is completely rebuilt. While I was rebuilding the unit I decided to get the twin stick shift rails and install them.
JB Custom Fabrication twin stick cable operated shifters are installed. This gives the option to operate the front and rear axle independently. Front wheel drive L an H. Rear wheel drive L and H or 4x4 L and H. With low range factored in the truck really is a 20 speed
A custom crossmember and stiffener had to be custom fabricated
Input and rear output yokes were upgraded to 1410. The front output is a 1350
There is a short 16" jack shaft that joins the transmission and transfer case. The trans side is a 1710 yoke and the transfer case side is a 1410
Truck and Interior
The truck was originally a gas truck with the 460 Cu in. engine
I had to modify the fuel tank setup. There are 2 fuel tanks in the truck. It was easier to use the mid tank as the main tank where fuel is drawn from and returned to. I have the fuel pump in the rear tank wired to a switch that I can use to fill the mid tank from the rear when needed
The intercooler and radiator are off of a 1997 powerstroke.
I had to build my own front radiator support. I need the larger style for the big diesel radiator and finding one for the 6.9 IDI in good shape was nearly impossible. LMC does not make one for this year of truck. I bought a front rad support for a 97 powerstroke and grafted the parts off it i need onto the 86
I decided to upgrade the braking system to hydroboost. The powersteering pump on the Cummins is setup to run this type of system, so it made sense to upgrade.
The entire under carriage is coated with Eastwood Undercarriage paint
4' Lift kit. 35x12.5 tires
All gauges are Autometer except for the Tach. The Tach is a Stewart Warner unit that uses a magnetic signal to count the teeth on the flywheel
Instead of messing around with the mechanical speedometer cable I decided to use a GPS speedometer from Autometer
The Gauges include- Pyrometer, oil temp, boost, lift pump fuel pressure, oil pressure, water temp, voltage, air pressure
New carpet for an automatic truck. I just cut the holes for the shifters where i needed them
Engine
1997 215 P7110 12 valve Cummins
Fully built from the ground up
all new seals and gaskets
Clevite performance H series main and rod bearings
billet oil squirters
ARP main studs
ARP rod bolts
ARP 625 head studs
polished and balanced crankshaft
Pistons bored .020 over
Mahle cast performance pistons. Early marine style big bowl 155 deg
Mahle rings and wrist pins
Billet freeze plugs
Keating machine billet front timing gear cover and tappet cover
Dual 12an breather lines with catch can
Deck was machined flat
Power Driven Diesel conical performance valve springs and chromoly retainers
Hamilton 178/208 camshaft
Hamilton 1.45" tappets
Hamilton extreme duty pushrods
Hamilton Cam bearing and bronze thrust plate
Resurfaced cylinder head
O-rings cut into the cylinder head
top hat style valve seals machined into the cylinder head
valve job
rocker arms machined for head studs
cummins .020 over head gasket
FASS 165gph fuel system
Bottom Sump installed on the fuel tank
All fuel lines upgraded to 1/2"
PDD AFC live
PDD 4000 rpm gov springs
5 x .016 PDD injectors
Torktek overflow valve
025 delivery valves
electronic fuel shutoff solenoid deleted. Cable system installed (more reliable)
DPS industrial style Fummins conversion exhaust manifold
BorgWarner S364SX-E Turbo. 64.5mm Compressor wheel Inducer Diameter. 68mm Turbine Wheel Outer Diameter
PDD performance air filter
Crazy Carls dual ram intake horn, billet intake plenum cover and grid heater delete
Sheid Diesel fuel lines
4" exhaust from the turbo to 5" stacks
PA Performance 200A 1 wire alternator
Transmission and Transfer Case
Transmission is an Eaton Fuller Road Ranger 10 speed RTO610. Completely rebuilt
1&3/4" input shaft
14" flywheel with a dual disc 1000 ft/lb rated pull style clutch. Manual adjusting type
SAE #2 bellhousing and starter
All hydraulics were removed from the truck for the clutch. I had to make a mechanical linkage with a bell crank on the frame to operate the clutch.
A substantial part of the floor had to be cutout to make room for the big transmission. I had to make a trans tunnel cover
A custom crossmember had to be fabricated to support the transmission
Onboard air is required to shift the ranges in the transmission so I decided to add air horns as well. The whole setup is from Hornblasters. Compressor, horns, wiring, and air line plumbing. The compressor can handle filling a tire and running small air tools
New shorter shift tower
The boot, valve, and shift knob came out of a Freightliner Cascadia
The transfer case is a divorced NP205 unit
Transfer case is completely rebuilt. While I was rebuilding the unit I decided to get the twin stick shift rails and install them.
JB Custom Fabrication twin stick cable operated shifters are installed. This gives the option to operate the front and rear axle independently. Front wheel drive L an H. Rear wheel drive L and H or 4x4 L and H. With low range factored in the truck really is a 20 speed
A custom crossmember and stiffener had to be custom fabricated
Input and rear output yokes were upgraded to 1410. The front output is a 1350
There is a short 16" jack shaft that joins the transmission and transfer case. The trans side is a 1710 yoke and the transfer case side is a 1410
Truck and Interior
The truck was originally a gas truck with the 460 Cu in. engine
I had to modify the fuel tank setup. There are 2 fuel tanks in the truck. It was easier to use the mid tank as the main tank where fuel is drawn from and returned to. I have the fuel pump in the rear tank wired to a switch that I can use to fill the mid tank from the rear when needed
The intercooler and radiator are off of a 1997 powerstroke.
I had to build my own front radiator support. I need the larger style for the big diesel radiator and finding one for the 6.9 IDI in good shape was nearly impossible. LMC does not make one for this year of truck. I bought a front rad support for a 97 powerstroke and grafted the parts off it i need onto the 86
I decided to upgrade the braking system to hydroboost. The powersteering pump on the Cummins is setup to run this type of system, so it made sense to upgrade.
The entire under carriage is coated with Eastwood Undercarriage paint
4' Lift kit. 35x12.5 tires
All gauges are Autometer except for the Tach. The Tach is a Stewart Warner unit that uses a magnetic signal to count the teeth on the flywheel
Instead of messing around with the mechanical speedometer cable I decided to use a GPS speedometer from Autometer
The Gauges include- Pyrometer, oil temp, boost, lift pump fuel pressure, oil pressure, water temp, voltage, air pressure
New carpet for an automatic truck. I just cut the holes for the shifters where i needed them
Comments
The plate with lifting eye on the trans tower location: Is that mount home made? Is it normal to use that are as a lift location?
Asking because I’m not seeing much in the way for lift locations on the Cummins 335 with 10spd.
B
Burl
July 25, 2025