The 2014 GMC Sierra and the art of towing

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CALGARY, Alta. — Southern Alberta is the ideal place to showcase the towing capabilities of the new 2014 GMC Sierra. Alberta represents an important market to GMC, accounting for a quarter of its Canadian truck sales. The southern reaches of the province provide a nice array of hills to challenge the new EcoTec3 engines. And Lundbreck, Alta. is home to the aptly named Sierra West Ranch, providing GMC with the perfect backdrop for the inaugural drives of its newest model.

The 2014 Sierra comes equipped with a new engine for quiet, efficient and capable towing as well as a full suite of trailering technologies to make the job easier, safer and more efficient for operators. About 60% of pickup owners use their trucks for trailering, according to GM customer surveys, and the redesigned Sierra was built with that in mind.

For two days in early July, I was given a nicely appointed 2014 GMC Sierra SLT 1500 crew cab to drive from Calgary to Lundbreck, Alta. There, I’d hitch on to a 30-ft. Sport Trek travel trailer – after an evening by the campfire, followed by a night in the trailer – and then pull it back to Bucars RV in Balzac, just north of Calgary.

Pulling a travel trailer weighing about 6,000 lbs behind a 2014 Sierra, I was close to the listed maximum towing capacity. However, I think GM was being modest when it set this limit, as there was ample power to maintain my speed at 95-100 km/h up even the steepest hills I encountered. And there are hills aplenty along Hwy. 22 in southern Alberta, some of them with grades of 7%. To be sure, the engine had to work hard on some of those long uphill climbs. At times, the rpm climbed to about 3,500 and fuel economy nosedived into the 28 litres per 100 km (L/100 km) range, but that’s still impressive given the hilly terrain, not to mention the fact I wasn’t being overly mindful of fuel economy; I was mashing the throttle up the hills to get a feel for the EcoTec3’s power. The previous day, hauling nothing but sailboat fuel, the Sierra averaged around 12 L/100 km on the drive south. (Published expectations are 13.3 L/100 km in the city and 9 L/100 km on-highway). Naturally, fuel economy while towing improved steadily as we reached the flatter sections of highway north of Longview.

The truck I was driving had the 5.3-litre V-8 engine under the hood, with 355 hp and 383 lb.-ft. of torque. If I was going to consistently be pulling a trailer this heavy, I’d likely have opted for the Max Trailering Package, which features a rear axle ratio of 3.73 and allows trailering of up to 12,000 lbs. That’s the beauty of the Sierra; you can virtually double the towing capacity by choosing the right combination of engine and rear differential.

The EcoTec3 engines that power the new GMC Sierra – as well as the Chevy Silverado – combine three design elements that contribute to its towing capability: direct injection; variable valve timing; and active fuel management.

Direct injection increases the compression ratios, which translates into greater horsepower and torque for pulling loads; variable valve timing acts like a racing cam to deliver maximum fuel when needed; and active fuel management slips the engine from eight-cylinder mode to four when less power is required, saving fuel.

There are three EcoTec3 engines available: a 4.3L V-6; 5.3L V-8; and a soon-to-be released 6.2L V-8, each mated to a six-speed automatic transmission. The smaller 4.3L offers towing capability at a lower price point, while the 5.3L and 6.2L offer greater versatility for pulling heavier loads.

When released, the 6.2L will be available with a whopping 420 hp and 450 lb.-ft. of torque, which when combined with 3.73 rear axle ratios will give you the ability to pull trailers weighing up to 12,000 lbs. GMC claims this will be the highest rating in the segment, making the Sierra an attractive option for those who are serious about towing.

Whatever the engine ratings, the new Sierra is chock full of features designed to improve comfort and safety while towing. Highway 22 is known for its gale-force crosswinds, which can be unsettling when pulling a trailer of any type. The Sierra’s StabiliTrak system offers trailer sway control that immediately dampens any sway resulting from crosswinds, abrupt steering inputs or oversized trailers. When the system senses trailer yaw, it intervenes by automatically applying the brakes and/or reducing engine power to bring the trailer back in line.

Before leaving the Sierra West Ranch, I activated Tow Mode via a switch on the shift lever. This modifies the transmission’s shift mapping to get the most out of the truck’s EcoTec3 engine, providing shift points that maximize power while initiating earlier downshifts to promote engine braking. When engaged, the system activates the Sierra’s Trailer Grade Braking feature, which utilizes an engine brake on downhill stretches to prevent the overheating and subsequent premature wear of the brakes. To engage the system, I just lightly tapped the brake pedal when cresting the hill and a message would soon pop up on the in-dash display, informing me the system was actively restraining the vehicle. This feature worked marvelously on my drive; I rarely had to touch the brakes on even the steepest downhill sections of road along my route. I was fully expecting to be pushed aggressively downhill by the heavy trailer, but this was not the case. Those of us who’ve pulled 53-ft. trailers know the importance of an effective engine brake, particularly in this part of the country. Novice drivers pulling too-big trailers over Rocky Mountain passes are as common as mosquitoes this time of year; I believe the towing features GMC has built into the Sierra have the potential to save lives.

Drivers who insist on using the brakes all the way down the hill will be afforded some additional forgiveness, thanks to GM’s Duralife brake rotors, which the company claims last twice as long as conventional rotors while producing less vibration. They’re less likely than some other rotors to overheat and cause a scare – or worse – on long downhill grades.

Also available on the 2014 Sierra is Hill Start Assist, which automatically engages when starting from a standstill on grades of 5% or more. The system applies the brakes for 1.5 seconds, giving the driver sufficient time to apply the gas without rolling backwards. This feature will be welcomed by drivers who plan to tow boats and have to contend with slippery launches, or those engaging in off-road hauling.

The new Sierra comes with a relocated integrated trailer brake control, which is now logically placed higher up on the instrument panel, to the left of the steering wheel.

“The integrated trailer brake controller used to be down at the bottom,” said Craig Couch, engineering program manager with GMC. Its previous location was less than ideal when struggling to regain control of an ornery trailer. Now, the gain setting can be easily adjusted without bending over, as Couch said, “Like you’re trying to find a quarter on the floor mat.”

Aside from all the towing functionality, there’s a lot to like about the Sierra from an operator’s perspective, particularly for those who’ll be using the truck for a combination of work and play. The new Sierra offers more features than have ever before been offered in a full-sized GMC pickup, and the truck I drove was equipped with most of them. Standard tie-downs in the bed help with hauling cargo and corner steps built into the bumper (deleted from the Sierra I drove) enable drivers to more easily climb up into the bed, even when the tailgate is up. The All-Terrain Package also provided some slick upgrades, including 18-inch chrome aluminum wheels, an off-road chassis package, full-feature front bucket seats and body-coloured grille surround and bumpers. 

The interior of this truck is pure luxury. Leather seats, an in-dash infotainment system with satellite radio
and navigation, Bose speakers, an intuitive dash with backlit gauges make the truck a joy to drive. The truck drives as smooth and quiet as a luxury sedan, but it’s also functional, with cleverly designed storage areas sized to accommodate commonly used business tools like smartphones, tablets and hanging folders. The Sierra offers no shortage of USB ports, power outlets, cup holders or storage areas.

It’s not an inexpensive truck. Decked out with all the bells and whistles, the truck I drove retails for north of $56,000. But GMC isn’t targeting penny-pinchers with this truck; it’s designed for the successful business owner or customer who wants a truck that screams success. With the new Sierra, GMC is courting what Sharon Sikorski, marketing manager, trucks and utilities, referred to as the “measure twice, cut once” crowd; operators who’ve achieved some measure of success in their lives or businesses and want a truck that shows it.

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  • We use to use GMC sierra for our towing service in Calgary. Due to so many modern cars and safety, we moved to Flatbed towing truck. Even though we use GMC truck for small cars or other services like lock-out or day to day operation like battery boosting.