2021 GMC Yukon Denali Duramax Diesel First Drive Review: Patience Pays

Wait, you’re gonna pay me to choose this engine? Yes, please!

Has GMC got a deal for you on its full-size Yukon SUV, provided you’ve already decided to splurge on the deluxe Denali trim series: Step down from the snarling 6.2-liter gas-hog V-8 into a purring, fuel-sipping, high-tech Duramax 3.0-liter turbodiesel, and the initial purchase price drops by $1,500. Cheapskates going for the base Yukon must pay $995 to upgrade from the 5.3-liter V-8, but the EPA reckons the GMC Yukon diesel can pay that G-note back in as little as five years, estimating the annual fuel savings at $150-$200, depending on whether you go for rear- or four-wheel drive. All you have to do is be patient enough to wait about 8.5 seconds to hit the mile-a-minute mark (based on our test of a similar Chevy Suburban Duramax), up from 6.1 seconds for the 6.2-liter and 7.2-7.5 seconds for the 5.3-liter.

Now let’s be honest: How often do you plan to drive your three-ton, gilded SUV with your foot pegged to the floorboard, sippy-cups sloshing, Goldfish crackers flying, your passengers’ necks flung back from their phone-gazing stoop? Not very. These jumbotrons are most pleasurable for all aboard when they’re driven judiciously. And that’s what diesels are great at.

Sure, the 6.2-liter can summon 420 horses—143 more than the diesel—if you continue whipping it to 5,600 rpm. But for the vast majority of the time when you’re just wafting around town it’s the torque that you appreciate, and this diesel summons precisely the same 460 lb-ft of twist as the V-8. Here’s the big difference: It does so by just 1,500 rpm—2,600 rpm sooner than in the gasser. This kind of effortlessly abundant low-end oomph gives the Duramax an alluring nonchalance at its torque peak. On those rare occasions when you actually experience the gas V-8’s torque peak, you may feel overexuberant at best, antisocial at worst.

Also alleviating the need to mercilessly flog this or any other engine in GM’s current full-size SUV lineup is the marvelous Hydra-Matic 10L80 10-speed automatic, which displays a knack for instantly summoning precisely the right ratio for every driving situation. Although all gearing is shared between these engines, the programming is perfectly tailored to match this very different engine’s characteristics.

And there’s more to like about this engine than just its quiet competence and parsimony. It truly sounds terrific. The inline-six-cylinder engine configuration is naturally balanced and inherently smooth, and GM has worked some magic in quelling most of that rattling noise diesels typically make. This one is quiet at idle, and when you do mash the accelerator, it makes a pleasing roar/growl sound that—while completely different from the iconic fourth-order rumble of a V-8—is equally pleasing. We wouldn’t be surprised to learn that GM benchmarked a BMW I-6 diesel for sound, like the N57 in a 535d we said “growls like a contented lion when you tickle the throttle.”

There are some sacrifices to be made. This engine gets the lowest payload and towing ratings of the lineup, but the difference is small: The 5.3-liter V-8 ranks best with 1,702-1,792 pounds of rated payload and 8,200-8,400 pounds of towing (ranges represent 4WD-RWD); the 6.2-liter comes next at 1,616-1,671 and 8,100-8,200, and the Duramax is rated for 1,571-1,580 and 7,800-8,100. The differences between these engines’ ratings varies by just 36-400 pounds—well within the margin of overload safety engineers design into vehicles like these.

Owning a diesel also means you won’t find your fuel on every single island of every filling station forecourt, and the fuel itself is oilier and smellier than gasoline. At least these jumbo GM diesels feature capless fuel fillers, so that’s one less thing you must touch. Being a modern emissions-compliant diesel also means it requires diesel exhaust fluid (DEF), also known as AdBlue. The DEF tank holds 5.3 gallons, and forum members report using DEF at a rate of about 1 gallon per 100 gallons of diesel, so the tank should only need refilling after 10,000 miles or so. And the large fuel filler door leaves plenty of room to maneuver the little plastic hose that connects to a 2.5-gallon DEF refill bottle while fueling the diesel tank.

To sum up, we heartily endorse the Duramax engine option now available in Chevy, GMC, and Cadillac full-size SUVs. The modest cost premium over a base engine can be quickly recouped, and the discount in a Denali will pay for the Air Ride Adaptive suspension and any of six fetching metallic colors.

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