Электромобиль GMC Sierra EV Denali тащит прицеп весом 10 тонн так же уверенно, как дизельный аналог

One image shows a large Jayco Eagle HT travel trailer behind the GMC Sierra HD AT4 diesel that Arek Bialobrzeski previously used to pull it. The other shows the same imposing camper behind his gray GMC Sierra EV Denali. That makes this a useful before-and-after comparison from one driver who has experienced the same trailer with two very different powertrains. It is not a controlled test because the route, weather, load and traffic may have changed, but it removes one of the largest variables from the usual diesel-versus-electric debate. Bialobrzeski previously identified his new truck as a 2025 Sierra EV Denali Max Range. After completing a reported 120-mile weekend trip at 70 mph, he shared his initial verdict with the GMC Sierra EV Group. “It handles a 10k lbs trailer like it’s 3k. Did a short weekend trip, 120 miles at 70 mph, did 0.7 m/kw.” He also said the electric motors’ immediate response made getting up to speed and merging onto the highway easier than it had been in the Sierra HD. His diesel truck reportedly returned approximately 8 to 9 mpg while pulling this trailer at 70 to 75 mph. His experience separates two questions that are often combined in electric-truck arguments. The first is how confidently a truck accelerates, merges, and controls a large trailer. The second is how far that truck can travel before it needs more energy. The Sierra EV appears to have answered the first question emphatically. At 0.7 mi/kWh, the second question becomes considerably more complicated. The Sierra EV Feels Stronger Even Though the Duramax Has a Higher Peak Torque Number Bialobrzeski’s reaction to the Sierra EV’s instant torque makes sense, although the specifications contain an interesting surprise. GMC rates the 2025 Sierra EV Denali Max Range at up to 760 horsepower and 785 lb-ft of torque in Max Power mode. It can accelerate from zero to 60 mph in less than 4.5 seconds and carries a maximum trailering rating of 10,000 pounds. The Extended Range version can be rated for as much as 10,500 pounds. For comparison, GMC’s current 6.6-liter Duramax turbo-diesel V8 produces 470 horsepower and 975 lb-ft of torque. The diesel has the larger peak torque figure, but the Sierra EV has considerably more horsepower and delivers its response through two electric motors without waiting for a transmission to select another ratio. That distinction helps explain why the EV can feel more effortless during an on-ramp merge even though the diesel produces a larger advertised torque number. The electric truck also brings standard all-wheel drive, a battery pack mounted within the vehicle structure, and an Air Ride Adaptive Suspension. Published tests and specifications place the Max Range Denali close to 9,000 pounds before attaching a trailer. That considerable mass, combined with immediate motor response and automatic suspension leveling, can make the truck feel planted while the trailer follows behind it. The photograph reinforces Bialobrzeski’s description. The Sierra EV appears level, composed and visually untroubled by the large Jayco. That stance should not be treated as proof that the combination is within every rating. Air suspension can sense added load and adjust the vehicle’s ride height, so a level body can hide the amount of weight pressing on the hitch. A scale ticket and the truck’s doorjamb labels remain more informative than visible rear suspension sag. The same caution applies to the claim that 10,000 pounds feels like 3,000. The Sierra EV can make the trailer feel lighter through the accelerator. It cannot turn 10,000 pounds into 3,000 pounds for the hitch, tires, trailer brakes, payload calculation, or an emergency maneuver. That is a compliment to the powertrain, rather than a reduction in the physical load. At 0.7 Mi/kWh, the Full Battery Projects to Roughly 144 Miles Bialobrzeski reported an average of 0.7 miles per kilowatt-hour while traveling approximately 70 mph. Expressed in the same format commonly used for other EV efficiency tests, that equals approximately 142.9 kWh per 100 miles. The Max Range Sierra EV uses a battery commonly reported at approximately 205 kWh. Multiplying that capacity by 0.7 mi/kWh produces a theoretical full-to-empty towing range of about 143.5 miles. GMC’s estimated unloaded range for the 2025 Max Range truck is 460 miles, so this towing projection represents approximately 31 percent of the advertised figure. That does not establish a guaranteed 144-mile range for every Jayco towing trip. Several important pieces of information are missing: Bialobrzeski did not provide his starting and ending battery percentages, elevation change, wind conditions, outside temperature, exact loaded trailer weight, or charging history. The truck’s 0.7-mi/kWh display may also have been rounded. The calculation is still useful for planning. Covering 120 miles at exactly 0.7 mi/kWh would consume approximately 171.4 kWh from the battery. If Bialobrzeski began at 100 percent, made the drive without charging, and had access to the full reported 205-kWh capacity, the math would suggest roughly 16 percent remained. That final battery percentage is an inference, not one he reported. A driver would also rarely plan a towing trip around reaching zero. Keeping a 10 percent reserve changes the picture: - Starting at 100 percent and stopping at 10 percent provides approximately 129 miles at 0.7 mi/kWh. - Starting at 80 percent and stopping at 10 percent provides approximately 100 miles. - A normal 10-to-80-percent fast-charging session replenishes enough energy for approximately 100 miles under the conditions Bialobrzeski reported. The Car Connection reports that GMC estimates approximately 40 minutes for a 10-to-80-percent session at a suitable charger. Actual charging time depends on battery temperature, charger output, starting percentage, and how long the truck can remain near its peak charging rate. This is where GMC’s advertised ability to add up to 100 miles of range in approximately 10 minutes needs towing context. The 100-mile figure represents added estimated range under favorable conditions. It does not promise 100 physical highway miles with a tall travel trailer attached. A 205-kWh battery spread across a 460-mile estimate implies roughly 2.24 miles per kWh. Bialobrzeski achieved 0.7 mi/kWh. If a charger added the same amount of energy represented by GMC’s 100-mile claim, that energy would support only about 31 miles at his reported towing efficiency. The charge port has not become slower. The truck and trailer are consuming the added energy more than three times as quickly. An Edmunds range test helps put the result in perspective. Its 2025 Sierra EV Max Range Denali traveled 507 miles while consuming 48.1 kWh per 100 miles. However, the Edmunds route averaged 40 mph and contained 60 percent city driving, making it very different from pulling a large camper at 70 mph. Bialobrzeski’s calculated 142.9 kWh per 100 miles is nearly three times that unloaded mixed-route consumption. Seventy MPH and the Jayco’s Shape May Matter More Than Its Weight The photographs show a trailer that is long, tall, and broad. Its rounded front cap helps, but the overall combination still presents an enormous surface to the air. Weight matters while accelerating and climbing. At a steady 70 mph, aerodynamic drag becomes increasingly expensive. A U.S. Department of Energy towing simulation modeled a Class 3 pickup with its frontal area doubled by a trailer. Under the modeled conditions, towing increased energy consumption by 76 percent at 60 mph on level ground. The study also found that aerodynamic loads associated with towing could add 44 percent to energy use in a fully loaded pickup. Those figures are not measurements of Bialobrzeski’s Sierra EV and Jayco, but they illustrate why trailer shape becomes so influential at highway speeds. Aerodynamic drag force rises approximately with the square of speed. Holding the wind, trailer and air density constant, increasing speed from 60 to 70 mph raises the aerodynamic portion of the load by roughly 36 percent. That does not mean the truck’s total energy consumption automatically rises by 36 percent. Rolling resistance, drivetrain losses, electrical accessories and elevation remain part of the total. However, a large travel trailer places a greater share of the burden on aerodynamics than an open utility trailer or a lower boat trailer. Bialobrzeski had hoped to achieve 1.0 mi/kWh. Moving from 0.7 to 1.0 would require a 30 percent reduction in energy consumed per mile. Reducing speed from 70 to 60 mph cuts the aerodynamic energy required per mile by approximately 26 percent. Because aerodynamics represent only part of total consumption, slowing down alone cannot guarantee 1.0 mi/kWh. It could still close a meaningful portion of the gap. Other Sierra EV reports support that possibility. One driver towing a 33-foot Keystone camper at approximately 60 mph reported between 1.0 and 1.1 mi/kWh. He observed that efficiency fell more noticeably as he approached 65 mph and described 60 to 62 mph as his preferred range. That trip projected to approximately 230 miles of towing range, although its route, weather, trailer weight and 2024 Sierra EV were different from Bialobrzeski’s combination. Another Sierra EV pulled a 28-foot Airstream 224 miles at approximately 60 to 65 mph and arrived with 14 percent remaining. That result implied roughly 260 miles of maximum towing range. The Airstream’s rounded aluminum body presents a cleaner aerodynamic problem than the large Jayco, which helps explain why trailer weight alone cannot predict EV towing range. These trips are not controlled comparisons. Together, they show how the same basic electric truck can move from approximately 144 miles of projected range to well over 200 miles depending on speed, trailer geometry and conditions. The Diesel Comparison Is Both a Cost Question and a Time Question Bialobrzeski said his diesel Sierra HD achieved approximately 8 to 9 mpg with this trailer at 70 to 75 mph. At those numbers, a 120-mile trip consumes between 13.3 and 15 gallons of diesel. The Sierra EV’s reported efficiency requires approximately 171.4 kWh from the battery to cover the same distance. The financial winner depends almost entirely on where the truck charges. At an electricity price of 20 cents per kWh, the Sierra EV’s battery-side energy cost would be approximately 28.6 cents per mile, or about $34 for 120 miles. At 40 cents per kWh, the figure rises to 57.1 cents per mile, or about $69 for the trip. At 50 cents, which is possible at some public fast chargers, the cost reaches approximately $86 before accounting for charging losses. At $4 per gallon, the diesel truck’s 8-to-9-mpg result costs approximately 44 to 50 cents per mile. At $5 per gallon, it costs approximately 56 to 63 cents per mile. Using Bialobrzeski’s reported efficiency, electricity breaks even with $4-per-gallon diesel at approximately 31 to 35 cents per kWh. With $5 diesel, the break-even electricity price rises to approximately 39 to 44 cents per kWh. Home charging can place the Sierra EV comfortably below those numbers in many regions. Long-distance towing often shifts energy purchases toward public DC chargers, where the price can approach or exceed the diesel equivalent. The 120-mile weekend trip represents one of the Sierra EV’s most favorable towing jobs. Bialobrzeski could leave home with a full battery, complete the journey without a public charging stop and potentially recharge at residential rates afterward. A 300-mile towing day would look different. Using a 10 percent reserve and Bialobrzeski’s 0.7-mi/kWh result, the truck could cover approximately 129 miles from a full start, then add roughly 100 miles during each 10-to-80-percent session. Reaching 300 miles would probably require two charging stops, assuming suitable stations were positioned along the route. The diesel truck’s 8 to 9 mpg sounds painful at the pump, but refueling takes minutes and does not require the driver to locate a charger that can physically accommodate the combined truck and trailer. For regional towing, the Sierra EV can offer the lower energy cost and better driving experience. During long interstate days, charging time, station placement and pull-through access become as important as the truck’s maximum range. A 10,000-Pound Trailer Can Reach the Payload Limit Before the Tow Rating Bialobrzeski described the Jayco as a 10,000-pound trailer. If that represents its actual loaded weight, his Max Range Sierra EV is operating at its published maximum trailering rating. If 10,000 pounds is the trailer’s gross vehicle weight rating rather than its measured loaded weight, the combination may have more capacity remaining. A scale ticket would settle that question. The payload calculation deserves equal attention. Published specifications place Sierra EV Denali payload at approximately 1,450 pounds, although the driver-side label on the individual truck is the controlling number. Factory options and accessories can reduce that available capacity. GMC’s conventional-trailer guidance recommends tongue weight of roughly 10 to 15 percent of the loaded trailer weight. A 10,000-pound trailer would therefore place approximately 1,000 to 1,500 pounds on the hitch, depending on its loading and balance. GMC also directs drivers to stay below the maximum tongue weight printed on the vehicle’s Trailering Information label. Using the published 1,450-pound payload figure as an optimistic reference: - A 1,000-pound tongue weight leaves approximately 450 pounds for the driver, passengers, hitch equipment and anything carried inside the truck. - A 1,200-pound tongue weight leaves approximately 250 pounds. - A 1,500-pound tongue weight would exceed the published payload figure before adding an occupant or any other cargo. That does not establish that Bialobrzeski’s truck was overloaded. The exact trailer weight, tongue weight, truck payload label, hitch rating, axle loads and passenger weight were not supplied. It does show why a maximum tow rating never tells the entire story. The Sierra EV may accelerate with a 10,000-pound trailer more confidently than the diesel HD. The HD can still provide considerably more payload and mechanical reserve for hitch weight, passengers and cargo. The Honest HD-to-EV Trade Bialobrzeski’s 120-mile trip is a success. The Sierra EV pulled a trailer he described as weighing 10,000 pounds, traveled at normal interstate speed, and gave him a more responsive merging experience than his diesel HD. There was no report of power reduction, instability, or an unplanned charging stop. The 0.7-mi/kWh result does not erase that success. It defines the conditions under which it happened. At 70 mph with this large Jayco, the Max Range truck becomes approximately a 144-mile full-pack tow vehicle. A 10-percent reserve reduces the first leg to around 129 miles. Once fast charging begins, the normal 10-to-80-percent window supplies approximately 100 miles. Slowing toward 60 mph could improve that number meaningfully. Leaving home fully charged could keep shorter camping trips away from public chargers entirely. Access to inexpensive home electricity could also give the Sierra EV an operating-cost advantage over the HD’s reported 8 to 9 mpg. Long travel days remain the difficult assignment. Public charging can approach diesel fuel costs, a conventional charging stop can take substantially longer than a diesel refill, and many charging locations still struggle to accommodate a truck with a large camper attached. The photographs capture both sides of the transition. The Sierra HD looks like the traditional answer to a 10,000-pound travel trailer: considerable payload reserve, long-distance endurance and rapid refueling. The Sierra EV offers a quieter and more responsive answer, with enough battery for regional trips and enough motor output to make the same trailer feel surprisingly light. The electric motors can hide the trailer’s mass from the accelerator. The battery, the hitch label and the air moving around the Jayco still know exactly how large it is. Would you accept approximately 100 miles between normal fast-charging stops for the Sierra EV’s quieter and stronger towing experience, or keep the diesel HD’s 8 to 9 mpg and faster refueling? Photos: Arek Bialobrzeski via GMC Sierra EV Group. About The Author Noah Washington is an automotive journalist based in Atlanta, Georgia, covering sports cars, luxury vehicles, and performance culture. His reporting focuses on explaining the engineering, design philosophy, and real-world ownership experience behind modern vehicles. Noah has been immersed in the automotive world since his early teens, attending industry events and following the enthusiast communities that shape how cars are built and driven today. His work blends industry insight with enthusiastic storytelling, helping readers understand not just what a car is, but why it matters. Noah is also a member of the Southeast Automotive Media Association (SAMA), a professional organization for automotive journalists and industry media in the Southeast. His coverage regularly explores sports cars, luxury vehicles, and performance-driven segments of the automotive industry, including the evolving culture surrounding Formula Drift and enthusiast builds. Read more of Noah's work on his author profile page. You can also follow Noah here: Set Torque News as Preferred Source on Google