RETURN OF THE ZR2

GM GETS BACK IN THE LINEUP

Well, that didn’t take long. Only a few short years ago, the mid-size truck market was all but hanging by a thread. The Ranger, Dakota, Colorado, Canyon and B-Series had all gotten the axe and the Tacoma and Frontier were left to wither and die from a lack of attention.

Fast-forward to the present day, and a major shift has taken place. The Colorado and Canyon are back, the Ranger is on its way and the Tacoma has not just received a complete makeover, but a full out off-road trail edition that comes as close to a purebred off-roader as anything south of the Jeep Wrangler.

Well, Toyota’s monopoly of having the only true mid-size hard-core off-roader will be a short and sweet moment in automotive history. Soon it will have some very stiff competition to contend with, the return of GM’s ZR2 nameplate that will first be plastered on the Chevrolet Colorado.

GM has now officially announced the addition of the ZR2 into the line-up later this year and on paper, it looks like it might just have the Taco on the ropes.

At the heart of the special off-road focused trim is the application of Dynamic Suspensions Spool Valve (DSSVTM) damper technology, produced by Canadian suspension gurus, Multimatic.

“Our engineers have been incredibly successful developing Corvette and Camaro performance variants with broad performance envelopes,” said Mark Reuss, executive vice president, Global Product Development. “The ZR2 applies

that same philosophy to off-road performance. You can go rock crawling on Saturday, desert running on Sunday, and comfortably drive to work on Monday. This truck can do it all, and do it all well.”

Compared to deflected-disk valving common on most dampers, the ZR2 employs spool valves that offer increased precision and manufacturing repeatability along with enhanced ride and handling performance both on- and off-road.

The Colorado ZR2’s DSSV dampers are position-sensitive. Their aluminum bodies each house two spool valves providing both compression and rebound damping optimized for everyday driving. During extreme off-road use, a third, piston-mounted spool valve delivers additional, uniquely-tuned, compression damping. The front dampers also employ a separate rebound valve, which comes into play when the suspension approaches full extension.

“A traditional, deflected-disc damper only offers two force-velocity curves for tuning,” said Mark Dickens, executive director, Performance Variants, Performance Parts and Motorsports Engineering, Chevrolet. “The ZR2 dampers offer six tuning curves for the front, four at the rear. For the driver, this translates to greater confidence and control in a wider range of driving experiences.”

Designwise, the ZR2 has a more aggressive side profile, with the suspension lifted two inches for greater ground clearance compared to a Colorado Z71. The front bumper of the ZR2 has tapered

ends to increase the tire clearance when approaching obstacles. The bumper also integrates a thick, aluminum skid plate protecting the radiator and engine oil pan, while an additional shield protects the transfer case. Above the bumper, the ZR2 features a more aggressive grille and hood – with black insert – to complement the other exterior changes.

The front and rear track has been widened by 90 mm (3.5”), with new castiron control arms for greater durability in off-road situations. As a result, the ZR2 offers greater wheel travel and stability while traversing steep grades. The ZR2 also features 17 x 8 inch aluminum wheels, in a pattern exclusive to the ZR2, wrapped in 31-inch Goodyear Duratrac off-road tires.

Another important feature is the four-wheel drive system that is particularly impressive for a mid-size truck. With classexclusive, electronic-locking differentials front and rear and Chevrolet’s AutoTrac transfer case, the ZR2 offers nine drive configurations:

• 2WD

• 2WD, locked rear differential

• Auto 4WD

• Auto 4WD, locked rear differential

• 4WD Hi, locked transfer case

• 4WD Hi, locked transfer case and locked rear differential

• 4WD Lo, locked transfer case

• 4WD Lo, locked transfer case and locked rear differential

• 4WD Lo, locked transfer case, locked front and rear differentials

GM says that extensive work was done to integrate the electronic lockers and allow them to seamlessly interact with the traction control, stability control, and hill-descent control. In addition, a new “Off-Road Mode” button, in combination with the traction control switch, allows the anti-lock brakes, traction control, and stability control calibrations to be tailored to different driving conditions. Off-Road Mode also alters the throttle progression and shifts calibrations to give the driver better control and responsiveness.

The ZR2 will receive the same powertrains as the standard Colorado, with an all-new 308 hp and 275 lb-ft 3.6L V-6, mated to a Hydra-Matic eight-speed automatic. The 181 hp and 369 lb-ft Duramax diesel will be particular appealing to the off-road and provide overland community.

There is a lot of air under that chassis; this could be a good sign.

Some usual trim badging will decorate the interior along with additional offroad tech.

Canada’s own Multimatic suspension manufacturer is responsible for what could prove to be game changing suspension dynamics.

An increase in approach and departure angles is obvious.