Chevrolet has introduced the all-new ’19 Silverado 1500 with a fresh, smaller engine, and it has also added to the off-road capabilities of the midsize Colorado pickup. We had the opportunity to drive the new four-cylinder Silverado and the dirt-savvy Colorado ZR2 Bison in Arizona. Come along as we give you details and first drive impressions of these two trucks.
A fascinating feature in the ’19 Chevy lineup is the availability of a four-cylinder engine in the fullsize Silverado. Its 2.7L displacement is similar in size to what you might typically find in a midsize pickup. However, Chevy packs the intake charge of this engine with a turbocharger and does some other tricks to derive 310 hp and 348 lb-ft of torque from this new powerplant that’s built in Spring Hill, Tennessee. That peak torque runs from about 1,500 to 4,000 rpm. The ’19 Silverado also sheds weight with this engine, resulting in a 380-pound decrease compared to an ’18 Silverado with the 4.3L V-6 engine.
The engineers started with a clean slate, building the new truck-specific engine with an aluminum block and cylinder head. The dual-overhead cam valvetrain uses four valves per cylinder, with an interesting twist. The action combines the Tri-power valvetrain with continuously variable valve timing, variable valve lift, and Active Fuel Management (cylinder deactivation). Solenoid actuators above the camshafts, along with the use of three cam profiles, allow the engine computer to vary the engine performance on the fly based on the performance demands at the time. Intake air is forced as needed using a dual-volute turbocharger with electronically controlled wastegate, combined with an intercooling system. The advanced turbo design can effectively benefit engine performance at low rpm and build further from there.
We drove a 2.7L turbo Silverado backed with its eight-speed automatic over city streets and highways and found it pleasantly responsive to throttle input, with little indication of turbo lag. This Silverado 4WD was outfitted with a 3.42:1 axle ratio. It pulled well up to highway speeds, even tackling 6 percent mountain grades with slight downshifting and more gentle input from the turbocharger.
Unloaded, we were impressed with the performance of the truck. Conceptually, Chevy’s goal was to build an engine that could go from sipping fuel running on two of its four cylinders when cruising by adjusting cam timing and fuel delivery, but then pull similar to a small V-8 engine when the forced induction was fully utilized. The 2.7L turbo engine acts like two different engines during low- and high-rpm operation. For those consumers that don’t haul heavy loads much or tow regularly, this truck may fill the bill for a pickup with good power combined with top-line fuel efficiency.
On the midsize, off-road side of things, Chevy is upping their game on the ZR2-edition Colorado by introducing the Bison. The ZR2 itself offers outstanding off-road capability with front and rear locking differentials and tuned Multimatic spool valve shocks. Designed in conjunction with American Expedition Vehicles (AEV), the Bison is now the top-of-the-line Colorado, incorporating more extras from the factory that enthusiasts might seek in the aftermarket after purchasing a truck.
AEV designed many of the upgrades on the Bison. Most notable at first glance are the front and rear stamped-steel bumpers. The front has replaceable corners with foglights and is designed to easily accept a Warn or ComeUp winch. The rear bumper includes recovery points, knock-out panels for additional lighting, and nerf tubes that protect the bed corners. Less visible are the five skidplates that protect all the vital areas under the truck. Chevy wanted durable protection underneath, but also wanted to stick to a tight weight budget at the same time. AEV opted to design relatively thin, but stiff, skidplates that are hot-stamped from boron-alloy steel, resulting in light skidplates that are far harder to dent, spring back from most impacts, and do not easily gouge as they slide over rocks they contact. When speaking with AEV President Dave Harriton, he stressed that each of the Bison factory upgrades is fully compliant with the engine cooling and crash impact standards used to test the Colorado.
The Bison is available with the V-6 gas engine and eight-speed automatic transmission, or the 2.8L Duramax diesel engine combined with a six-speed automatic. You can choose whether you prefer the brisker acceleration of the gas powerplant or the torquey pull and extended driving range of the diesel powerplant. Bison is also available in both Crew Cab and extended cab models. We slipped behind the wheel and drove the Bison on surface streets, highways, and off-road. The on-road suspension behavior is tuned much to our liking. It’s slightly firm, as an off-road truck should be, so handling on the street is comfortable without excessive sway. On dirt, the amazing Multimatic shocks soak up ruts and bumps on two-track roads and smooth out as speed increases. We also had the opportunity to tackle some mild rockcrawling in the Bison and left impressed with what the truck could do. The IFS flexes well, and combined with the articulation of the rear axle and locking differentials, we could walk the truck through some good obstacles.
As an aside, Chevy has more exciting news regarding the Colorado. The company just released a line of race-proven parts for the ZR2 based on performance testing on Chad Hall’s desert race truck. Upgrade parts include race-tuned shocks, jounce bumpstops, A-arms, rear traction bar, steel driveshaft, exhaust, and other parts allowing owners to build their own high-performance truck using factory components. There is also an optional AEV snorkel designed specifically for the Colorado. Overall, the Bison is quite capable straight off the dealer lot, plus there is the capability for any ZR2 owner to push to higher performance levels if desired.
Engine: 2.7L turbocharged DOHC I-4
Bore & stroke (in): 3.63 x 4.01
Block material: 380 T5 cast aluminum (cast-iron cylinder inserts)
Cylinder head material: 356 T5 cast aluminum
Compression ratio: 10.0:1
Firing order: 1-3-4-2
Ignition system: High-energy coil-on-plug
Max engine speed: 6,100 rpm
Horsepower (hp @ rpm): 310 @ 5,600
Torque (lb-ft @ rpm): 348 @ 1,500-4,000
Manufacturing location: Spring Hill, Tennessee
Vehicle: 2019 Chevy Colorado ZR2 Bison
Package price: $5,750
Bison upgrades include: front and rear steel bumpers, high-strength boron steel skidplates, wider fender flares (can clear 33-inch tires), Dual Sport wheels, rear differential skidplate, flow-through “Chevrolet” Bow Tie, AEV logo headrests and floor mats