The Endangered Bighorn

Written by: Tony Youngblood

Note: This story was partially published in Wheels of Times (mid 90’s) and later fully published in Old Time Trucks (’04).

The first two Bighorns were 9500’s. They were prototypes. I don’t think Chrysler could make it’s mind up on what to call the truck, either by name or number. The parts book lists the Bighorn as a DNT 1000 for the tandem axle and DN for the single axle, but behind that it is also listed as CNT950 and CN950.

Basically there were two styles of Bighorns built. The top of the line was the Custom Cab Bighorn consisting of the following options:

  • 350 Cummins
  • 13 Speed Fuller or 16 Speed Spicer. The 16 Speed Spicer had a chrome tower that covered the gear shaft lever and air lines.
  • 12,000 front axle, some with front brakes, which my truck (Tony Youngblood) has. This is very rare. Most are 38,000 rears being Reyco 101 on the ’73 and ’74 models with inboard brake drums , and Reyco 102 on the ’75 models with outboard brake drums.

Other options to keep the weight down were aluminum crossmembers, rear skid and intermediate, front bumper, hubs front and rear, differential carries, battery boxes, centerfuse drums, aluminum cab supports (which I found was only on the ’73 models,) fuel tanks, and a transmission case on Spicer transmissions. Also, the rear wheels were lightweight hi-tensile steel wheels, while the front wheels were lock rim style aluminum wheels. In these areas Dodge was trying to watch the weight of the truck.

Today’s truckers would scream bloody murder if they knew that the hood ornament alone weighed 14 pounds, but Dodge also was working on that problem. The 14 pound original Ram on the long nose was being replaced from stainless steel to a 2 pound aluminum ram. There was also a slight difference in the design of some of the Ram’s heads. I have five ram’s heads and two are different. One is chrome instead of stainless. I know this is original because I bought it from Chrysler.

The nice Bighorn also came with a 1500 Cubic inch radiator, which is one of the biggest if not the biggest radiator ever put in an over the road truck. In front of it were Kysor shutters. The shutters were built to remain open if the truck had air conditioning and it was on.

The 13 speed Fuller was usually a RTO 9513 with Rockwell SQHD rears and a 4.44 ratio. These options were offered by Dodge, but you could get a number of rear axle ratings. The ratings range from 34,000 to 44,000 with a 140,000 turnpike rating. Any ratio’s were offered with the ratings.

The front axle was mostly FF921 on 12,000 and FG on the 16,000 pounds. Shocks were also offered on the custom cab with an air suspension Western Stabilizer on the rear.

Original picture from Dodge literature

Frames were offered at any wheel base and were of heat treated Hi-Tensile Steel- 110,000 PSI on the 10 1/8 X 3 1/4 X 1/4. A 5/16″ thick frame rail was optional. There were 1810 series propeller shafts on most of the trucks I have seen. 

Exhaust systems on most Bighorns consisted of a 5″ chrome elbow starting under the vertical muffler curving around and under the rear of the cab where they connected to a flex pipe and then a solid pipe joining the turbo. The muffler was held at the top rear corner of the cab by and aluminum bracket. The lucky Bighorn owners with dual exhaust systems had a better balanced looking truck, making the cab look bigger behind the massive hood. Otherwise without the mufflers and shields the cab looked like an after thought, which was small for the hood.

Fuel tanks on the Bighorn came in 75 and 100 gallon tanks. On the ’73 and some early ’74 Bighorns, the aluminum fuel tank had a very wide step built in making it easier to get in and out of the cab. Also, the tank was made out of better shined aluminum. They narrowed the step half the width for the rest of the ’74 and ’75 Bighorns, making access a little harder and the aluminum was not as good a grade. I’ve seen one Bighorn with original 100 gallon factory fuel tanks, which are very rare. This truck is owned by Tom Corigliano. The tanks were produced by Synder Tanks.

The steering on the Bighorn came two ways. Power steering was a Ross HF-64 Box. The manual steering was a Ross 7D500. The steering wheel in the custom cab consisted of a white 20 inch wheel with the Dodge logo in the horn button. The logo was a yellowish gold color on a white background. This was the only truck ever built by Dodge with the horn button that color. The electric sea shell horns were mounted on the top left corner of the radiator. The high note or low note were not much use unless the truck was not running, but the dual Grover horns made up the difference. Also the steering column was neatly designed with an adjustment on the left side. The column had a custom suede jacket to surround it, hiding the steering shaft and turn signal wires. It looked very neat and high class. Being able to drop the steering column all the way down was also nice.

    With this all the way down, the driver was able to pull four screws and lay the complete dash over. The piano hinge system made the back of all the instruments and air valves available. Certified Cummins mechanics and other dealers have said that it was one of the best dash arrangements they have ever seen. There was also a wiring diagram on the back of the glove box that became visible when the dash laid over. There were plenty of gauges in the dash. They were all built by Stewart and Warner and are waterproof bi-torque gauges. Everything from voltmeter, engine oil, trans. oil, axle oil, exhaust pyrometer oil pressure, dual air, amps, fuel and water. The early speed and tachometer had the Chrysler Penstar in the center or the high beam light (in the center). A few came with electric tachometers and speedometers, but there was a lot of trouble with them.

The inside of the Custom Cab Dodge was clean and its systems were close at hand. The seats were any type offered by Bostrom with a Bostrom Viking companion seat. They were pleated and matched the color of the vinyl trim on the door, roof inserts (also pleated), back panel and the console between the two seats. The inside door grab handles were polished aluminum with a square shape. On the 1975 Bighorn the outside grab handle matched the inside grab handle. On the ’73 and ’74 they were round chrome handles on the outside which made the ’75 easier to spot. In the ceiling was a housing storing either AM or AM/FM stereo. The speakers were in the back corner of the cab, just about head level. The glass was tinted all around which along with the integral air conditioning system helped keep the cab cool. The air conditioning used the same housing in the cab as the heater. The evaporator fit in with the heater radiator. The condenser was in front of the shutters. The compressor was a York or Tec with a 3 speed switch.

Original picture from Dodge literature

Outside the cab was all class. This was the best looking and smartest designed trucks ever to hit the road. There were chrome Signal Stat bullet lights on top. An aluminum front bumper had Perlux road lamps, dual horns, stainless steel exhaust shields and a choice of cab, hood and frame color made for quite a site. Choice of four striping combinations were also available.

Appearance Items

  • Polished Aluminum: Front Bumper, Front Wheels, Batter Box Covers (early models only)
  • Polished Stainless Steel: Muffler Shields, Mirrors, Front Grille and Vertical bars
  • Chrome: Bullet Lights, Horns, Fuel tank straps

For some reason the American Bighorn came with Aluminum Front Wheels and either Reyco or Hendrickson steel buds on the rear. In Canada most Bighorns came with spoke wheels, those on the rear being Hendrickson.

The type of air lines were Aeroquip re-usable fitting with Parker-Hannefin flex-lines. Nylon lines inside of cab and in instrument panel were color coded and easy to trace.

Crossmembers were original style Dodge used in C-cabs and Cabovers with extra strength. Instead of a single crossmember in place, they took 2 and bolted them back to back with 8 bolts, hardened washers and aircraft type self locking nuts.

Filters were Air-Donaldson Cycolpak 16′ oil full flow 4 qt. Endline mounted plus bypass Fleetguard 14 qt.

Fuel CumminsDetroitWater Cummins
FleetguardAC-T 74AC-T 65Fleetguard
Four 6 VoltPrestoline 12 VoltDelco-SI 65-AMPPVC with eyeslot terminalsCircuit Breakers

The cab on the Bighorn most people think is the same as the C-cab, but it it not. Of course the doors are the same, but the firewall is different and braces inside the cab are also different. Two outside panel extensions where the 950 emblem goes, fill the space between the door and hood. Full sprayed-on closed cell foam on firewall toe board and under cab floor help keep out heat and noise. Also closed cell foam sheet between metal and floor mat along toe board and dash. Floor mat had double closed backing insulation. The cab of the Bighorn was produced by Checker Cab Company. The part number is 3731-905 where as the C-cab part number is 3731-904.

Back to the difference between the “Custom Cab” and the “Plain Jane”. The cheap Bighorn (as I call it) basically has a 290 Cummins, 10 speed Fuller, 38,000 rears on Hendrickson and 12,000 front with no brakes. There were no shocks, no aluminum crossmembers, hubs, bumper or any other weight saving items. There were no stainless steel mirrors, polished sill plates, center consoles or pleated panels. They had no power steering and the radiator was of the smaller 1200 cu. in version. Also all wheels were steel not aluminum. There was a Texas oil that had about 18 of them. I know 4 were stripped, John Ernest has 2, Asa Hall has 1, some I have stripped out, and a few still exist.

There were 261 Bighorns produced, and I believe there to be between 70-80 still in existence. Since it was a small scale production and 25 years since Dodge has built a truck the Bighorn has become a widely sought after collectible. They say in the near future a fully restored, or original unrestored Bighorn could bring around $100,000 , which is very possible. Not bad for and old truck!  

Original picture from Dodge literature

All past and present Bighorn owners will tell you they think this is the best all around truck produced by anyone. When produced it was so far ahead of its time that is would blend right in with today’s trucks. Chrysler itself was partly to blame for the down fall of the Bighorn. The dealers wouldn’t stock the or service them. The Federal Government developed an anti-skid law that Chrysler couldn’t meet to their specifications. I have been told by a Dodge Dealer owner that as Dodge was introducing the Bighorn to dealer’s in Detroit, word was being spread around that Chrysler was going to end production on all of their Heavy-Duty trucks.