The RAM 2500/3500 Mega Cab I, specifically the 3500 model equipped with the 6.7 HO Cummins turbocharged diesel engine and automatic transmission, represents a significant offering in the heavy-duty pickup truck segment. Introduced for the 2012 model year, this configuration aimed to provide a balance of substantial towing capacity, robust performance, and a degree of everyday usability. It falls within the fourth generation (2010-2018) of the RAM heavy-duty lineup, known internally as the DS platform. This variant occupied a position above the base engine options, targeting buyers who required serious power for work or recreational towing, but didn’t necessarily need the ultimate capabilities of the higher-output Cummins variants.
Technical Specifications
| Brand | RAM |
| Model | 2500/3500 |
| Generation | 2500/3500 Mega Cab I |
| Type (Engine) | 3500 6.7 HO Cummins TD (350 Hp) Automatic |
| Start of production | 2012 |
| End of production | 2012 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Pick-up |
| Seats | 5-6 |
| Doors | 4 |
| Fuel Type | Diesel |
| Weight-to-power ratio | 9.6 kg/Hp, 104.4 Hp/tonne |
| Weight-to-torque ratio | 3.1 kg/Nm, 323.4 Nm/tonne |
| Power | 350 Hp @ 3000 rpm |
| Power per litre | 52.3 Hp/l |
| Torque | 1084 Nm @ 1500 rpm (799.52 lb.-ft. @ 1500 rpm) |
| Maximum engine speed | 3500 rpm |
| Engine Model/Code | ETJ |
| Engine displacement | 6690 cm3 (408.25 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 107 mm (4.21 in.) |
| Piston Stroke | 124 mm (4.88 in.) |
| Compression ratio | 17.3:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Turbocharger, Intercooler |
| Valvetrain | OHV |
| Engine oil capacity | 11.4 l (12.05 US qt | 10.03 UK qt) |
| Coolant | 21.4 l (22.61 US qt | 18.83 UK qt) |
| Kerb Weight | 3352 kg (7389.9 lbs.) |
| Max. weight | 4763 kg (10500.62 lbs.) |
| Max load | 1411 kg (3110.72 lbs.) |
| Trunk (boot) space – maximum | 1628 l (57.49 cu. ft.) |
| Fuel tank capacity | 129 l (34.08 US gal | 28.38 UK gal) |
| Permitted trailer load with brakes (12%) | 6260 kg (13800.94 lbs.) |
| Length | 6309 mm (248.39 in.) |
| Width including mirrors | 2009 mm (79.09 in.) |
| Height | 1882 mm (74.09 in.) |
| Wheelbase | 4077 mm (160.51 in.) |
| Front track | 1742 mm (68.58 in.) |
| Rear (Back) track | 1732 mm (68.19 in.) |
| Minimum turning circle (turning diameter) | 15.4 m (50.52 ft.) |
| Approach angle | 14.0° |
| Departure angle | 24.2° |
| Ramp-over (brakeover) angle | 15.8° |
| Drivetrain Architecture | The Internal combustion engine (ICE) drives the rear wheels of the vehicle. |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 6 gears, automatic transmission |
| Front suspension | Double wishbone |
| Rear suspension | Leaf spring |
| Front brakes | Disc |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Tires size | 245/70 R17; 265/70 R17; 275/70 R18 |
| Wheel rims size | 7.5J x 17; 8J x 17; 8J x 18 |
Powertrain & Engine Architecture
At the heart of this RAM 3500 lies the 6.7-liter Cummins inline-six diesel engine, designated the ETJ code. This engine is a robust, over-head valve (OHV) design known for its durability and low-end torque. The “HO” designation signifies a higher output version compared to the standard 6.7L Cummins offered in the 2500 series. The engine utilizes a common-rail direct fuel injection system, delivering fuel at extremely high pressures for optimized combustion. A variable geometry turbocharger with an intercooler further enhances performance by increasing air intake and reducing intake air temperature. The 6.7L Cummins is renowned for its ability to withstand significant modifications and maintain reliability. Paired with the engine is a six-speed automatic transmission, designed to handle the substantial torque output. This transmission features electronic shift control and is optimized for towing and hauling applications. The automatic transmission was chosen to broaden the appeal of the truck, offering ease of use compared to the standard manual transmissions.
Driving Characteristics
The 350 hp and 1084 lb-ft of torque delivered by this powertrain configuration translate into impressive real-world performance. While not as quick accelerating as lighter-duty trucks, the RAM 3500 with the 6.7 HO Cummins excels in situations requiring substantial pulling power. The automatic transmission provides smooth shifts, although it may not be as responsive as a manual transmission. The gear ratios are optimized for towing, prioritizing low-end grunt over outright speed. Compared to the standard 6.7L Cummins (around 305 hp), the HO version offers a noticeable increase in power, particularly at higher RPMs. However, it doesn’t match the performance of the higher-output Cummins variants (often exceeding 370 hp) which were geared towards maximum towing capacity. The substantial weight of the truck, especially in Mega Cab configuration, is always apparent, but the engine provides ample power to overcome this.
Equipment & Trim Levels
The 2012 RAM 3500 Mega Cab I with the 6.7 HO Cummins and automatic transmission was typically available in several trim levels, including STX, SLT, Laramie, and Limited. The base STX trim offered a functional interior with vinyl upholstery and basic amenities. The SLT trim added features like cloth upholstery, power windows and locks, and a basic audio system. The Laramie trim elevated the interior with leather upholstery, heated front seats, and a more advanced infotainment system. The Limited trim represented the pinnacle of luxury, offering premium leather, wood trim, and a host of convenience features. Standard equipment across most trims included air conditioning, a tilt steering wheel, and a basic instrument cluster. Optional extras included a navigation system, a premium sound system, and various towing packages.
Chassis & Braking
The RAM 3500 chassis is built around a heavy-duty frame designed to withstand the stresses of demanding work. The front suspension utilizes a double wishbone setup, while the rear suspension employs leaf springs. This configuration provides a comfortable ride, even when the truck is heavily loaded. Braking duties are handled by disc brakes on all four wheels, coupled with an Anti-lock Braking System (ABS) for enhanced safety. The rear axle ratios varied depending on the specific configuration and intended use, with options ranging from 3.73 to 4.10. Tire sizes typically ranged from 245/70R17 to 275/70R18, depending on the trim level and wheel options.
Market Reception & Comparison
The 2012 RAM 3500 with the 6.7 HO Cummins and automatic transmission was generally well-received by critics and consumers alike. It was praised for its powerful engine, comfortable ride, and spacious interior. Fuel economy, as expected for a heavy-duty diesel truck, was not a strong point, averaging around 14-17 mpg in real-world driving. Compared to the standard 6.7L Cummins, the HO version offered a noticeable performance improvement, but at a slightly higher price point. Compared to competitors like the Ford Super Duty and Chevrolet Silverado HD, the RAM 3500 was often lauded for its refined interior and comfortable ride quality. Reliability was generally good, although some owners reported issues with the turbocharger and fuel injection system.
Legacy
The 6.7 HO Cummins engine, paired with the six-speed automatic transmission, has proven to be a durable and reliable powertrain. These trucks continue to be popular on the used car market, particularly among those seeking a capable and dependable work truck. Proper maintenance, including regular oil changes and fuel filter replacements, is crucial for ensuring the longevity of this powertrain. While the 2012 model year represents an early iteration of the fourth-generation RAM heavy-duty trucks, it remains a capable and well-regarded vehicle, offering a compelling combination of power, comfort, and reliability.
