First Drive: 2020 Chevrolet Silverado 2500/3500HDs
Rolling into the throttle of the '20 Chevrolet 3500HD Crew Cab 4x4 dualie and feeling the power from the 6.6L Duramax diesel as it gets a 15-ton equipment trailer up to speed was a unique experience for us. It's the heaviest trailer we've pulled with a GM pickup, and it consisted of a John Deere dozer sitting on the Big Tex gooseneck beaver-tail trailer. It was daunting to see the pair in the rearview mirror, but it felt totally under control.
That is, in part, because the new Chevrolet HDs finally have the towing muscle to handle the biggest trailering jobs most of us would ever undertake with a pickup. A '20 Regular Cab 2WD longbed 3500HD Duramax-powered dualie is SAE J2807-certified up to 35,500 pounds, and the 4x4 we were driving on a closed course is rated to tow an impressive 31,400 pounds in gooseneck/fifth-wheel configuration. If we'd been on the open road, trailering such a load would require a Commercial Driver's License (CDL).
As the boost in the 6.6L turbodiesel peaks and the all-new 10-speed automatic snicks quickly and smoothly from First to Second gear, it's clear GM has learned a lot from the past decade when it comes to its heavy-duty pickups and what consumers want in a tow rig.
The new Silverados don't dominate in every towing/hauling category, but a day behind the wheel of both gas and diesel 2500/3500HDs, towing trailers of different types and sizes, leaves little doubt this newest generation will make any driver's towing experience safer and more convenient than ever before.
Bigger & Better
The '20 Silverado HDs are longer, taller, wider, more robust, and more refined than the generation they replace—it is impressive. For example, the standard 6.0L gas engine found in the '19s has been replaced by a healthy 401hp direct-injected 6.6L V-8 that makes 464 lb-ft of torque; the Allison six-speed in the Duramax has been replaced by a GM-built, Allison-approved and -branded 10-speed automatic; and the frame and drivetrain components from the transfer case to the axles are more robust than the '19s. It all adds up to a significant rise in trailering and hauling capacity across the board, so GM can claim, for now at least, the "King of Tow" crown.
As mentioned earlier, a '20 Regular Cab 2WD longbed 3500HD Duramax-powered dualie is SAE J2807-certified to tow up to 35,500 pounds. The rest of the heavy-duty '20 Silverados can now tow anywhere from 14,500 to 31,500 pounds depending on trailer type and the cab/engine configuration. In comparison, the '19 HDs were rated from 8,800 to 23,100 pounds.
Another notable change: GM is now putting each vehicle's max tow ratings on a driver-side doorjamb sticker according to the VIN, so consumers don't have to search for their truck's tow ratings.
But the new HDs we drove offer a lot more than just their ability to pull the biggest of toy haulers and equipment trailers. They offer a level of refinement, comfort, and safety features that are breaking new ground when it comes to making the task of towing easier and more convenient, regardless of one's skill level.
A New Look
Anyone who has driven an HD pickup knows seeing things in close proximity is a challenge, especially when towing a box trailer or big toy hauler. The new GM Advanced Trailering System provides a clear view in every direction.
Tapping the camera symbol on the infotainment screen brings no less than eight HD Valeo cameras online, giving the driver a choice of 15 unique views, including a "transparent" trailer view that lets you "see" through the trailer.
The multi-view system lets you zoom in on both the bed and the hitch ball, see a wide view down both the sides of the trailer, get an overhead view, a view looking down the back of the trailer (or slide-in camper), or down at the front bumper. There's even a camera option that allows you to see inside the trailer. There are no blind spots that we could see except under the truck.
The '20 Chevrolet HDs also come standard with a number of other advanced technologies that make trailering safer and more convenient. For example, the integrated brake controller allows you to store multiple trailer configurations; Tow/Haul remains on for up to four hours between key cycles and reminds you it's engaged; Auto Park Brake Assist locks the truck in place so it doesn't creep when hitching up the trailer; and Park Grade Hold Assist engages the brakes at all four wheels for parking on hills.
The new trucks also come standard with Trailer Sway Control, Proactive Rollover Avoidance, Diesel Exhaust Braking (Duramax), Auto Grade Braking, and Hill Start Assist and Hill Descent Control. Need more? An optional in-vehicle trailering app tests trailer lights and monitors trailer tire pressures among other towing-related functions.
Extendable towing mirrors with forward-facing spot lamps are standard, as is an engine block heater on the Duramax (optional for the 6.6L gas) that's now integrated into the front bumper on the driver side. GM also relocated the Duramax's Diesel Exhaust Fluid (DEF) tank farther back on the frame and placed the DEF fill next to the diesel filler neck. The '20s also have a DEF fuel gauge indicator on the Driver Information Center.
Four-wheelers who plow will like the ease with which a plow package can be installed without drilling holes in the bumper or cutting up the front fascia. When the plow is removed, the Silverado HD maintains a smooth, integrated appearance without any visible hardware. The 6.6L gas engine can also be ordered with dual 220-amp alternators to handle the extra electrical demands.
The wheelbase of the Crew Cab was stretched 5.2 inches, which allows for a bigger interior with more leg and headroom for the driver and passengers, and there's an abundant amount of storage spaces throughout the Crew Cab models we drove.
The beds are made of multipiece inner panels, and the standard "short" beds are 3 inches longer and have nearly 7 inches more useable width than the '19 truck, and they include steps in front of the rear wheelwells and on the corners of the rear bumpers.
Both standard and longbeds sport a dozen fixed tie-downs, with the corner ones rated to hold up to 500 pounds. Options include a 120V outlet on the passenger side of the bed and a power up/down tailgate for those that want to rest their biceps.
The biggest change current Duramax owners will notice is the level of performance the 10-speed automatic brings to the big pickups. GM replaced the venerable Allison-built six-speed automatic with a clean-sheet, GM-built, Allison-branded 10L1000. The new automatic is a joy to drive, providing smooth, crisp, close-ratio gear splits that truly complement the pulling power of the Duramax's 910 lb-ft of torque.
"The all-new 10-speed transmission with closer gear spacing allows the engine to operate in an optimal range at all times with varying load and terrain conditions," said Jaclyn McQuaid, GMC Vehicle Chief Engineer, Heavy Duty Trucks.
The GM-built 10L1000 meets all of Allison's highest standards and is a clean-slate design inside and out, including a variable-rate pump; high-performance clutch packs and solenoids; a factory-installed PTO pump option; and a stiffer, one-piece housing that bolts directly to the transfer case instead of having to use an adapter like the "old" six-speed. All of the internals are immersed in Dexron Ultra-Low Viscosity fluid.
Unlike the previous Allison, the 10L1000 is designed to put all of the 6.6L Duramax's 910 lb-ft of torque to the ground in First gear when the transmission is in the Tow/Haul mode. When the Tow/Haul mode is off, the new 10-speed starts in Second. The low 4.54:1 First, combined with the strength of the new internal parts, gets the heaviest of loads, moving easily even with a "tall" 3.42:1 axle ratio.
There are no other axle ratios offered because the new GM 10-speed provides better acceleration and puling power with its 7.2:1 overall gear spread (the six-speed Allison was 5:1), closer gear splits, and deeper low gear than the old Allison, according to David Ames, the assistant chief engineer on the '20 Silverados.
Six forward gears with close-ratio gearing, combined with the Duramax's turbo exhaust braking, enable the driver to manually shift to a lower gear, or set cruise control, to maintain a more precise speed when descending steep grades than could ever be accomplished with the previous Allison.
We experienced all of that driving the new HDs in the mountains, using grade braking and manual downshifts while towing a mini-excavator behind a '20 Silverado 2500 LT Crew Cab 4x4 high in the Oregon Cascades. The truck maintained whatever speed we selected down 6 percent-plus grades with the 12,500-pound load in tow. The shifts were swift and velvety smooth, too.
An even bigger refinement over the Allison six-speed is that the 10L1000 locks up the torque converter in First, greatly reducing heat buildup. (The six-speed Allison didn't lock up until it was in Third, according to Ames.)
"Locking up the torque converter right away when towing is by far the biggest thing you can do to keep an automatic cool, because a lot of the heat is generated by that torque converter being open," said Ames. "So locking it up in First gear, and holding it locked, really reduces heat when towing."
Towing on Gas
The new 6.6L small-block, which has a longer stroke and 21 percent more torque than the 6.0L gas engine it replaces, also gets a transmission transplant in the form of a Hydra-Matic 6L90 six-speed automatic fitted with Tow/Haul mode. And, as with the diesels, the gassers are relegated to one axle ratio—3.73:1.
We towed a mini-excavator along a section of highway skirting Mount Bachelor, near Bend, Oregon, with a 2500HD Crew Cab 4x4. The 5,000-foot-plus altitude and 12,000-pound trailer load was a true test of the six-speed automatic's gearing and the new V-8's 464 lb-ft of torque.
The 4.03:1 First gear and 3.73 axle gearing had no problem getting the load moving and maintaining speed at the higher altitude on more level terrain, but the 2500HD struggled when it came to maintaining 50 mph up a 6 percent grade towing near its maximum conventional towing capacity of 14,500 pounds. At sea level the small-block would probably deliver more favorable results.
Our initial observation is the 6.6L gas engine would be ideally suited for fleets that don't want to make the monetary investment in the Duramax, or consumers who will be using their '20 2500HD to regularly trailer loads that are less than 10,000 pounds.
Cooler Is Better
Transmission and chassis upgrades contributed heavily to the dramatic increase in the Chevrolet 2500/3500HDs' towing capacities. But making the cooling system more efficient and beefing up the drivetrain components were also key contributors to the rise in trailering muscle.
According to Nicola Menarini, the Director of Program Execution for the Duramax diesels, keeping the 6.6L Duramax cool under heavy load was one of the first hurdles the engineers had to overcome in getting the new SAE J2807 maximum towing certification that's significantly higher across the board than GM attained in the '19 HDs.
Better cooling was achieved by opening up the upper part of the grille, making the active hoodscoop larger and replacing the previous 25-inch fan with a massive 28-incher that now sucks air through the radiator. The new fan is driven by dual belts and has a special offset blade design to eliminate airflow-induced harmonics. GM is also offering active aero shutters on the new HDs that are said to further improve engine efficiency.
Menarini also pointed out that the 6.6L Duramax has a larger, more efficient engine oil cooler located in the block's valley. The combination of more air flowing through the radiator and engine compartment (across the oil pan), along with a higher-capacity oil cooler, resulted in lowering engine temperatures enough to pass the stringent J2807 cooling requirements leading to the higher tow ratings.
Having the gearing, torque, and cooling to handle the demands of trailering heavy loads is one thing, but those are of no relevance if the rest of the drivetrain can't handle the forces needed to get the power to the ground.
GM's engineers beefed up the size of the '20 HD's drivelines by 30 percent. While the single-rear-wheel 2500/3500HDs retain the same American Axle & Manufacturing (AAM) 11.5-inch ring gear in the rear axlehousings and 14.1x1.3-inch disc brakes as '19, the 3500 dual-rear-wheel (DRW) models now run AAM's massive rear differential with a 12-inch ring gear, tree trunk-sized 4.25-inch axletubes, and 14x1.6-inch brake rotors front and rear.
Also an option on the 4x4 HD models is GM's AutoTrac active two-speed transfer case, which electronically controls torque transfer between the front and rear differentials, seamlessly shifting between 2WD and 4WD based on road/traction conditions.
A little twist of the rotary dial on the upper left of the dash allows the driver to toggle between multiple traction modes in the 4x4s. Having AutoTrac as part of that system would be an option worth considering for off-road adventurers and those who use their new HDs for plowing snow or live in areas prone to harsher winter conditions.
Our limited time with the '20 Chevrolet HDs never afforded us the opportunity to see how the new pickups would perform off-pavement or in the snow. What was readily apparent is that GM did a commendable job making trailering with the new trucks, be it job related or recreational, simpler and safer, and the bundle of new technologies found in the '20 Silverado HDs simply makes all drivers better.
We loved the performance with the new 10-speed "Allison" coupled with the Duramax. It's a sweet power package for four-wheelers trailering their toys to any destination. We'd like to see an 8- or 10-speed automatic offered in the 6.6L gas-powered HDs for those towing at altitude or pushing those trucks' towing limits.
Overall, GM's continuing evolution of safety, comfort, and convenience features we saw on display in the '20 Chevrolet Silverado HDs make any job or journey much more pleasant. With five trim levels to choose from (Work Truck, Custom (2500HD), LT, LTZ, and High Country) across gas and diesel platforms, it should be easy to find one to fit both budget and need. Prices of the '20 Chevrolet HDs were not available at time of publication.