It's Official: 2027 Silverado Engine Specs Are Here, With 481 HP and 13,700 Pounds of Towing

Back in June, when Chevrolet revealed the next-generation Silverado, we made you a promise: no guessing at horsepower, and no repeating rumors. We said we would publish the real 2027 Silverado engine specs the moment GM made them official. Not a minute before. That moment is today. GM has released full output, towing, and payload figures for all four 2027 Silverado 1500 engines. The headline is a big one. The all-new 6.6L V8 makes 481 horsepower, the most of any Silverado ever. The all-new 5.7L V8 gives the Silverado a best-in-class 13,700-pound max tow rating. Here is everything GM announced, what it means, and what is still to come.

The 2027 Silverado engine lineup at a glance

Four engines, one truck. Every 2027 Silverado 1500 engine is paired with a 10-speed automatic transmission, and two of the four are brand new. Here are the official GM numbers for the Silverado 1500:

Official GM ratings released September 17, 2026. Maximum towing and payload vary by cab, bed, drivetrain, trim, and packages. The 13,700-lb rating requires a Double Cab or 2WD Crew Cab Short Bed with the 5.7L V8 and Max Trailering Package. Full disclosures are at the bottom of this post.

The 400 is back: the all-new 6.6L V8

If you grew up around Chevy trucks, the number 400 means something. GM's new 6.6L V8 displaces 400 cubic inches. That brings a legendary Small Block size back to the Silverado for the first time in decades. It replaces the outgoing 6.2L and makes 481 horsepower and 501 lb-ft of torque. GM says that makes it the most powerful naturally aspirated V8 in the half-ton class. It is also the most powerful engine ever offered in a Silverado, period.

It is rated to tow up to 9,700 pounds and carry up to 1,510 pounds of payload. This is the engine for people who want the most power a Silverado has ever had. Maybe that is for merging onto the 8 with a trailer behind you. Maybe it is just because a 481-horsepower truck sounds like a good idea. We agree.

The 350 returns too: the all-new 5.7L V8

The second new engine is just as significant for anyone who tows. The all-new 5.7L V8 is a 350-cubic-inch Small Block, another name that needs no introduction. It steps in for the outgoing 5.3L with 402 horsepower and 428 lb-ft of torque. Pair it with the Max Trailering Package and the Silverado 1500 earns a best-in-class maximum tow rating of 13,700 pounds. GM says no other truck in the segment tows more.

That 13,700-pound figure applies to specific configurations. You need a Double Cab in 2WD or 4WD with the standard bed, or a 2WD Crew Cab with the short bed. Both require the 5.7L and the Max Trailering Package. Other builds will be rated lower. When the order guide arrives, we will break the numbers down by configuration on our 2027 Silverado 1500 page.

All-new sixth-generation 6.6L V8 engine blocks on the line at GM's Flint Engine Operations. Look closely and you can spot the "400" cast into the block. Photo: General Motors.

What makes a sixth-generation Small Block different

Both new V8s are built on GM's sixth-generation Small Block architecture. It is the same family as the new 6.7L V8 in the 2027 Corvette. They share one detail with every Small Block since 1955: cylinder bores spaced 4.40 inches apart. More than 100 million engines have been built on that spacing. Everything else has been reworked. According to GM, the key changes are:

• More displacement. GM lengthened the piston stroke by 6 mm to grow the 5.3L into the 5.7L and the 6.2L into the 6.6L.
• Higher compression for more efficient combustion, plus larger throttle bodies and new intake manifolds with tuned runners to move more air.
• Dual-fuel injection. Direct injection and port injection work together. That lets the engine run in its best power, efficiency, and emissions window across more driving conditions.
• A new lubrication system with a continuously variable oil pump, an on-engine oil cooler, and reworked oil feed locations for more consistent oil pressure.

The first 5.7L and 6.6L engines are being built at GM's Flint Engine Operations in Michigan. More capacity is planned at Tonawanda, New York and St. Catharines, Ontario. GM says its teams expect to log more than 1.5 million miles of real-world, on-road validation before the trucks reach dealerships. You can read the full announcement on the GM newsroom.

TurboMax and Duramax got better too

The two carryover engines did not just carry over. The enhanced 2.7L TurboMax remains the standard engine. It gains 40 horsepower and 25 lb-ft of torque, for a total of 350 hp and 455 lb-ft. GM credits a new turbocharger, an upgraded fuel injection system, improved thermal management, and redesigned pistons. It keeps its best-in-class standard torque title. It now pairs with the 10-speed automatic for smoother shifts and stronger towing. It also carries the highest payload rating in the lineup at 2,340 pounds. Worth knowing if your bed does more work than your hitch does.

The Duramax 3.0L Turbo-Diesel returns as the only diesel in the half-ton class. It makes 305 horsepower and 495 lb-ft of torque with a 12,000-pound max tow rating. GM made a round of durability updates. Those include a next-generation NOx sensor, revised DEF level indicators, and updates to the pistons, turbo vanes, sealing, and fuel injectors. The big news for road-trippers is a new available 34-gallon fuel tank. Paired with the diesel, GM estimates a highway range of more than 900 miles. That is roughly San Diego to Sacramento with a few hundred miles to spare.

Standard on every 2027 Silverado engine: a 10-speed automatic

One more change worth calling out on its own. For 2027, every Silverado 1500 engine, from the TurboMax to the 6.6L V8, is matched to a 10-speed automatic transmission. No more 8-speed on the lower trims. The new 34-gallon tank is also available with the 5.7L and 6.6L V8s, not just the diesel. Long-haul V8 buyers get the extra range too.

What we still do not know

In the interest of staying your accurate source, here is what GM has not released yet:

• Pricing. MSRP by trim has not been announced. GM says it will come in a future update.
• Fuel economy. No EPA ratings yet, other than the GM-estimated 27 highway mpg behind the diesel range figure.
• The exact on-sale date. GM still says the next-generation Silverado 1500 arrives at dealerships "later this year."

The moment any of those become official, they go on our 2027 Silverado 1500 page. We keep it updated with every confirmed detail. It now has the full engine breakdown, all seven trims, the interior and tech story, and answers to the questions we hear most.

What this means if you are truck shopping in San Diego

If you tow, the 5.7L V8 just became the truck to wait for. A 13,700-pound rating covers most boats headed to Mission Bay. It covers most travel trailers headed to the desert, and most equipment trailers headed to a job site. If you want the most powerful Silverado ever built, the 6.6L is the one, and 481 horsepower speaks for itself. If you rack up highway miles, the Duramax and its 900-mile range are hard to argue with. And if you mostly haul in the bed, do not overlook the TurboMax. It quietly has the best payload rating of the four.

If you would rather not wait, the current 2026 Silverado 1500 is on our lot in La Mesa today. Our 2026 Silverado towing guide can help you match a truck to your trailer right now. Either way, our team is happy to talk through which engine fits how you actually use a truck. No pressure, just straight answers.