The GMC Envoy II, produced between 2003 and 2006, represented the second generation of GMC’s mid-size SUV offering. Built on the GMT360 platform, shared with the Chevrolet TrailBlazer and Buick Rainier, the Envoy II aimed to provide a blend of truck-based durability with improved on-road refinement. The 4.2i 24V variant, equipped with a 4.2-liter inline-six engine producing 275 horsepower and paired with a four-speed automatic transmission, occupied a significant position in the Envoy II lineup, offering a balance between power and affordability. It was positioned as a step up from the base 4.2-liter engine without the added cost of the more powerful 5.3-liter V8 option.
Technical Specifications
| Brand | GMC |
| Model | Envoy |
| Generation | Envoy II (GMT360) |
| Type (Engine) | 4.2i 24V (275 Hp) Automatic |
| Start of production | 2003 |
| End of production | 2006 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | SUV |
| Seats | 5 |
| Doors | 5 |
| Fuel consumption (urban) | 14.7 l/100 km (16 US mpg, 19.2 UK mpg, 6.8 km/l) |
| Fuel consumption (extra urban) | 10.7 l/100 km (22 US mpg, 26.4 UK mpg, 9.3 km/l) |
| Fuel consumption (combined) | 12.3 l/100 km (19.1 US mpg, 23 UK mpg, 8.1 km/l) |
| Fuel Type | Petrol (Gasoline) |
| Weight-to-power ratio | 7.6 kg/Hp, 132.3 Hp/tonne |
| Weight-to-torque ratio | 5.6 kg/Nm, 179.4 Nm/tonne |
| Power | 275 Hp @ 6000 rpm |
| Power per litre | 66.1 Hp/l |
| Torque | 373 Nm @ 3600 rpm (275.11 lb.-ft. @ 3600 rpm) |
| Maximum engine speed | 6300 rpm |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | LL8 |
| Engine displacement | 4160 cm3 (253.86 cu. in.) |
| Number of cylinders | 6 |
| Engine configuration | Inline |
| Cylinder Bore | 93 mm (3.66 in.) |
| Piston Stroke | 102 mm (4.02 in.) |
| Compression ratio | 10:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated engine |
| Valvetrain | DOHC |
| Engine oil capacity | 6.6 l (6.97 US qt | 5.81 UK qt) |
| Coolant capacity | 13.1 l (13.84 US qt | 11.53 UK qt) |
| Kerb Weight | 2079 kg (4583.41 lbs.) |
| Max. weight | 2494 kg (5498.33 lbs.) |
| Max load | 415 kg (914.92 lbs.) |
| Trunk (boot) space – minimum | 1162 l (41.04 cu. ft.) |
| Trunk (boot) space – maximum | 2268 l (80.09 cu. ft.) |
| Fuel tank capacity | 83.3 l (22.01 US gal | 18.32 UK gal) |
| Permitted trailer load with brakes (12%) | 2858 kg (6300.81 lbs.) |
| Length | 4866 mm (191.57 in.) |
| Width | 1894 mm (74.57 in.) |
| Height | 1826 mm (71.89 in.) |
| Wheelbase | 2869 mm (112.95 in.) |
| Front track | 1603 mm (63.11 in.) |
| Rear (Back) track | 1576 mm (62.05 in.) |
| Ride height (ground clearance) | 203 mm (7.99 in.) |
| Minimum turning circle (turning diameter) | 11.1 m (36.42 ft.) |
| Approach angle | 33.9° |
| Departure angle | 23° |
| Drivetrain Architecture | Rear wheel drive |
| Drive wheel | Rear wheel drive |
| Number of gears and type of gearbox | 4 gears, automatic transmission Hydra-Matic |
| Front suspension | Double wishbone |
| Rear suspension | Independent multi-link suspension |
| Front brakes | Ventilated discs |
| Rear brakes | Disc |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic Steering |
| Tires size | 245/65 R17 |
| Wheel rims size | 7.0J x 17 |
Powertrain & Engine Architecture
The heart of the Envoy II 4.2i was the LL8 engine, a 4.2-liter (253.86 cubic inches) inline-six cylinder powerplant. This engine utilized a cast iron block with aluminum cylinder heads, a configuration chosen for its balance of durability and weight savings. The engine featured a double overhead camshaft (DOHC) valvetrain with four valves per cylinder, contributing to its respectable power output. Fuel delivery was managed by a multi-port fuel injection system, providing precise fuel metering for optimal combustion. The 4.2L engine was known for its relatively smooth operation and adequate power for everyday driving. The four-speed Hydra-Matic automatic transmission was the sole transmission option for this variant. While not the most modern transmission by the mid-2000s, it provided smooth shifts and was generally reliable. The transmission’s gear ratios were tuned for a balance of acceleration and fuel economy, prioritizing usability over outright performance.
Driving Characteristics
The 275 horsepower and 373 lb-ft of torque delivered by the 4.2-liter engine and four-speed automatic provided adequate, though not exhilarating, performance. Acceleration from 0 to 60 mph was typically in the 7.5 to 8.5 second range, depending on vehicle load and road conditions. Compared to the 5.3-liter V8-equipped Envoy II, the 4.2-liter felt noticeably less powerful, particularly when towing or climbing hills. However, the 4.2-liter offered a more refined driving experience, with less engine noise and vibration. The automatic transmission’s shift points were generally well-timed, but downshifts could sometimes feel hesitant. The rear-wheel-drive configuration provided a more traditional SUV driving feel, but lacked the all-weather capability of four-wheel-drive models.
Equipment & Trim Levels
The Envoy II 4.2i typically came standard with features such as air conditioning, power windows and locks, a CD player, and cloth upholstery. Higher trim levels, such as the SLE, added features like leather upholstery, heated seats, a premium sound system, and alloy wheels. Optional extras included a sunroof, a navigation system, and a rear entertainment system. The interior design was functional and straightforward, with a focus on durability rather than luxury. The dashboard layout was typical of GM vehicles of the era, with clearly labeled controls and a relatively simple design.
Chassis & Braking
The Envoy II utilized a body-on-frame construction, providing a robust and durable chassis. The front suspension featured an independent double wishbone design, while the rear suspension employed an independent multi-link setup. This suspension configuration aimed to provide a comfortable ride and decent handling. The braking system consisted of ventilated discs at the front and solid discs at the rear. Anti-lock brakes (ABS) were standard equipment, enhancing safety and control during emergency braking situations. The steering was rack-and-pinion with hydraulic power assist, providing responsive and precise steering feel.
Market Reception & Comparison
The GMC Envoy II 4.2i was generally well-received by critics as a capable and affordable mid-size SUV. It was praised for its comfortable ride, spacious interior, and adequate power. However, some critics noted that the 4.2-liter engine felt underpowered compared to the V8 option, and the four-speed automatic transmission was beginning to feel dated. Fuel economy was average for its class, with combined fuel consumption around 19 mpg. Compared to the Chevrolet TrailBlazer, the Envoy II offered a slightly more upscale interior and exterior styling. The Buick Rainier, sharing the same platform, aimed for a more luxurious experience but at a higher price point.
Legacy
The LL8 4.2-liter inline-six engine, while not known for being a particularly groundbreaking design, proved to be a relatively reliable powerplant. Common issues included oil leaks and occasional sensor failures, but overall, the engine was considered durable and long-lasting. The four-speed Hydra-Matic transmission also had a generally good reputation for reliability. Today, the Envoy II 4.2i can be found on the used car market at relatively affordable prices. While it may not offer the latest technology or the highest levels of performance, it remains a viable option for those seeking a dependable and spacious SUV. Its simplicity and relatively low maintenance costs make it an attractive choice for budget-conscious buyers.
