Let’s be honest: no one is buying a Chevrolet Silverado HD for performance. These trucks are usually bought by customers who have a heavy trailer to tow, so things like acceleration, top speed and braking distance aren’t as important as items like towing capacity, payload or fuel economy.
That didn’t stop YouTube channel The Fast Lane Truck from comparing the real-world 0-60 mph time of the 2020 Chevrolet Silverado 2500HD with the 6.6-liter L8T V8 to the 2020 Silverado 2500HD with the 6.6-liter L5P Duramax diesel V8, though. While not an important metric in these two workhorses, the channel’s experiment is still quite useful for comparing the actual differences in performance between the two trucks—as horsepower and torque figures on paper don’t always translate into the real world how you might think.
TFL Truck assembled a 2020 Silverado HD Custom with the 6.6-liter gas V8 and a 2020 Silverado HD High Country with the Duramax diesel engine for its comparison test. The gas truck is a little bit lighter, as it’s not as well-equipped and the gas V8 is much lighter than the diesel, but the diesel has much more power and torque. If you need reminding, the L8T V8 is rated at 401 horsepower and 464 pound-feet of torque, while the L5P diesel V8 makes 445 horsepower and a meaty 910 pound-feet of torque.
Another factor affecting the results of TFL Truck‘s test is the transmission. The gas truck is stuck with a GM six-speed automatic, whereas the Duramax gets the much newer and more advanced 10-speed automatic. The location of the test is also a mile above sea level, so TFL Truck‘s results may be a bit faster than if you were at a lower geographic location.
The results? With two-wheel drive mode engaged, the gas truck accelerated from 0 to 60 mph in 9.05 seconds, while the drag from four-wheel drive lowered the time to 9.22 seconds. The diesel truck liked the four-wheel drive high mode a bit more, though, accelerating from 0 to 60 mph in 8.00 seconds with two-wheel drive and 7.90 seconds with four-wheel drive engaged. We expected the diesel truck to be quicker, but were actually impressed with the performance of the much less torque-rich gas truck. Weight is playing a big factor here, as we mentioned above.
Check out the full video embedded below to hear TFL Truck‘s complete impressions of these new heavy-duty Chevys.
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Comments
I’ll bet that the gas engine version running on 105 octane propane, will beat the diesel on acceleration. Remember that the power rating on the 6.6 gasser on different than GM rates the car engines. The car engines are all rated on 93 octane fuel, but the 6.6 is rated on regular 87 octane. The 464 pounds feet of torque on the 6.6 with 87 octane, will be about 503 pounds feet of torque on E85 gas because of it’s much higher octane, especially with the very high 10.8 to one compression ratio on the 6.6 gas engine. propane is about 7 points of octane higher than E85, so the max torque will be even higher on LPG than the 503 Lbs feet on E85. I’m just about to order a truck now, but want GM to use the running results for the data feed they can get. I’m expecting to run about 40,000 miles per year, but might sell off the truck after two years to get the heavier 6500HD medium duty version when they offer a bigger gas engine, which will also be setup as a dual-fuel gas/propane version. The air suspension option on the Silverado medium duty trucks is a big attraction. The bigger engine will also allow me to haul more weight. GM might offer the new design 8.0 liter big block or a larger LS series 6.6 liter with a longer crankshaft to get over 7 liters. Torque at a lower RPM is the secret for any work truck, and a longer stroke based on the 6.6. liter will offer that.
TruckTrend rated the old 6.0 gas at 8.5 sec 0-60 in an article dated Oct. 20, 2014.
In Aug 2008 they ran a Suburban HD 0-60 in 7.8 sec on the 3.73, 6.0, 6L90 setup.
I expected the new 6.6 liter LT engine to be faster, not slower, than the old 6.0
Are the slower times on the gas engine an elevation penalty?
A mile above sea level will make it much slower. This article has it backwards. Also, forced induction is less affected by this.
One must consider the altitude as well. Turbos help at altitude as they spool a little faster in the lighter air. German WW2 fighter used turbos in some models to overcome the pressure drop at altitude. The 6.6 gas was probably only able to pull 80% of it’s torque at that altitude.
Chevy trucks came a long way with there stylish exterior why would u ruin it now with this ugly looking style chevy u lost my business I’m worth 10 pickups a year. Not no more guess dodge will earn my business now what a drag..
Cause a portion of the market likes the snoz aggressive look. For a more traditional look there is GMC. I agree with you and if money wasn’t a factor I would buy the GMC over the Chevy in a heartbeat
Say what you want about the newest generation. I LOVE MINE!!!
At one point I managed 29.2 mpg with my Duramax!!!
It hauled out 16,000 lb fifth wheel with no effort!!!