Everything You Need to Know About the 6.2L Supercharged HEMI V8

A guy at a truck stops outside Amarillo once told me his TRX gets worse gas mileage than his old diesel truck. He said he’d still buy it again. That trade-off sums up the 6.2L HEMI well. It’s a supercharged V8 that Chrysler put in everything from the Challenger to a half-ton pickup. It’s the engine that made “700 horsepower from the factory” sound normal. Here’s what it is, what it costs to own, and where you’ll find it.

Quick specs at a glance:

Engine Specifications and Design

The 6.2L HEMI shares its basic aluminum block with the smaller 5.7L and 6.4L HEMI engines. But it’s not just a bigger version of those engines. It uses a forged steel crankshaft, forged connecting rods, and stronger pistons. These parts are built to handle boost pressure. The naturally aspirated HEMIs never see that kind of pressure.

The most important part sits on top: the supercharger. It’s an IHI twin-screw unit, 2.4 liters on the standard Hellcat engine and 2.7 liters on the Redeye and Demon. A supercharger forces extra air into the engine, which lets it burn more fuel and make more power. Before that air reaches the cylinders, it passes through an intercooler, which cools it down. Cooler air is denser and packs more oxygen, so the engine can make more power without overheating. This setup is why a basic pushrod V8 design can make supercar-level power.

Compression is lower than the naturally aspirated HEMIs, at about 9.5:1. That’s on purpose. A boosted engine already has extra pressure inside the cylinder from the supercharger, so a lower compression ratio helps prevent knock, which is when fuel ignites too early and can damage the engine. Chrysler also used stronger head bolts, a reinforced block, and bigger fuel injectors than the 6.4L, since a supercharged engine puts more stress on everything downstream of it.

Horsepower: It Depends on What You’re Driving

The same basic engine makes very different power depending on the vehicle:

• Challenger/Charger Hellcat: 707 hp, 650 lb-ft of torque
• Challenger/Charger Hellcat Redeye: 797 hp, 707 lb-ft of torque
• Challenger SRT Demon: 808 hp on regular pump gas, 840 hp with the Demon Crate kit and race fuel
• Jeep Grand Cherokee Track hawk: 707 hp, 645 lb-ft of torque
• Durango SRT Hellcat: 710 hp, 645 lb-ft of torque
• Ram 1500 TRX: 702 hp, 650 lb-ft of torque

None of that difference comes from a different engine block. It comes from tuning, pulley size, intercooler size, and exhaust design. We drove the TRX shortly after it launched. That much torque in a half-ton truck is hard to describe until you feel it yourself. Read our full TRX drive review here.

Reliability: Better Than the Horsepower Number Suggests

A 700-plus horsepower supercharged engine sounds risky on paper. Early model years did have some real problems. A few owners saw supercharger bearing failures, extra oil use, or ignition issues under heavy boost. Chrysler fixed most of these problems through production changes and updated software in later years.

The bottom end of the engine holds up well. The forged internals aren’t just a marketing detail. They’re the reason these engines can handle daily boost without breaking. Owners who tow, track their vehicle, or run mild aftermarket tunes often report six-figure mileage on the stock engine, as long as they stay on top of oil changes.

The real risk isn’t reliability. It’s the cost when something does break. A supercharger rebuild or a transmission repair on these engines is expensive. This isn’t a cheap engine to fix. Keep that in mind, especially if you’re buying used.

Fuel Economy: About What You’d Expect

Nobody buys a supercharged HEMI to save money on gas, but the numbers are still worth knowing. The Challenger Hellcat is rated around 13 mpg city and 22 mpg highway. The Ram TRX is heavier and less aerodynamic, so it’s rated much lower: 10 mpg city, 14 mpg highway, 12 mpg combined, according to EPA fuel economy estimates.. Drive either one hard, or tow with the TRX, and real-world numbers drop even further.

Here’s what that means in dollars. At $3.50 a gallon, a TRX averaging 11 mpg costs about $315 to drive 1,000 miles. A 5.7L Ram averaging 16-17 mpg costs closer to $210 for that same distance. Over a year of regular driving, that gap adds up to real money.

Some versions use cylinder deactivation, which shuts off half the cylinders during light cruising to save a little fuel. It helps some, but it won’t turn this into a fuel-efficient engine. If gas mileage matters more to you than 0-60 times, the 6.4L HEMI or a diesel option makes more sense.

What Vehicles Use the 6.2L HEMI

• Dodge Challenger SRT Hellcat, Hellcat Redeye, and Demon
• Dodge Charger SRT Hellcat and Hellcat Widebody
• Dodge Durango SRT Hellcat
• Jeep Grand Cherokee Trackhawk
• Ram 1500 TRX

Worth knowing if you’re shopping new: the current Ram TRX-successor models switched to a twin-turbo six-cylinder Hurricane engine instead of the supercharged V8. If you want the HEMI specifically in a truck, you’re now looking at the used market, and the supply keeps shrinking.

Key Features That Set It Apart

• Forged rotating assembly: built to handle daily boost, not just occasional hard runs
• Cylinder deactivation: used on some models to soften the fuel penalty during light driving
• Upgraded oil cooling: helps manage the extra heat that comes with boost
• Launch control and line lock: useful for drag strips, less useful for daily driving or trails
• Different tuning per vehicle: the same short block delivers low-end torque in the TRX and a higher-revving feel in the Challenger

Want to see how this compares to Chrysler’s non-supercharged big V8? Check out our 6.4L HEMI Apache engine breakdown, plus a real-world fuel economy test on the 6.4L in a Power Wagon.

Real-World Example: A TRX Owner’s First 40,000 Miles

Spec sheets only tell you what an engine can do on paper. What it’s actually like to live with is a different question. A Ram 1500 TRX owner in Texas posted his first 40,000 miles of ownership on a TRX owners’ forum. He splits his driving between daily commuting and towing a 24-foot travel trailer most weekends. His story matches what we hear from other long-term 6.2L owners.

His truck is stock, no tune, no pulley swap. In 40,000 miles, he had one warranty repair: a knock sensor that triggered a check-engine light and got replaced for free at 22,000 miles. Everything else has run the way it did on day one. He changes oil every 6,000 miles with the factory synthetic oil. Spark plugs get replaced at 30,000 miles, earlier than on naturally aspirated HEMIs, since boost puts more stress on the ignition system. The original supercharger belt is still on the truck as of his last update.

Fuel economy told a rougher story. Driving solo around town, he averaged 11-12 mpg, below even the EPA’s already low city rating. Towing the trailer dropped that to 7-8 mpg. On mountain grades in New Mexico, he saw it drop to 5-6 mpg under heavy load. That’s a real number to plan a road trip’s gas budget around, not just a spec on paper.

What stood out more than the fuel bill was how the truck handled with the trailer attached. A supercharged engine doesn’t need to build RPM or wait for a turbo to spool before making power. It’s just there right away, at almost any speed. Passing another vehicle on a two-lane highway while towing is one of the more stressful things you can do behind the wheel. He said he could make the pass in third gear without downshifting. His old 5.7L-powered Ram needed two gear drops and a run-up in RPM to do the same thing.

He also flagged a few wear items for anyone shopping a used TRX. Listen for a rising whine from the supercharger, which can be an early sign of bearing wear. Check the intercooler pump, since it’s a known weak spot after 50,000 miles. And budget for tires. The factory 35-inch all-terrain tires don’t last long on a truck that puts 650 lb-ft of torque to the ground at idle. He was on his second set of tires by 35,000 miles.

None of this makes the truck a bad buy. It’s just the honest cost of owning something this powerful: a durable core engine, predictable wear items that cost more than average, and fuel bills that match what 700 horsepower actually demands.

Buying Used: What to Check

Looking at a used Hellcat-powered vehicle instead of buying new? Check these things before you sign anything.

Supercharger service history. Ask if the belt or pulley has ever been replaced. Listen for any unusual whine or rattle at idle and under boost. A supercharger rebuild is the most expensive repair this engine can need.

Modification history. These engines get tuned often, with pulley swaps, aftermarket exhausts, or upgraded intercoolers. That’s not automatically a bad sign, but a heavily modified engine has usually seen more stress than a stock one. It may also mean the factory warranty is gone. Ask the seller for a tune history if they have one.

Transmission condition. The 8HP75 automatic transmission behind these engines is generally solid, but hard launches and aggressive tunes can wear it out faster. Rough shifts or hesitation under load are worth a second look before you buy.

Cooling system. Boosted engines run hotter than naturally aspirated ones under load. Ask directly about any overheating history, especially if the vehicle has been tracked or used for towing in hot weather.

Tire wear pattern. Uneven wear can point to alignment problems from hard driving, which is common on these vehicles since it’s easy to break traction.

None of these checks are unique to the 6.2L HEMI. You’d check the same things on any high-output performance engine. They just matter more here, since so many of these vehicles get driven hard from day one.

How It Compares to the 6.4L HEMI

The question we hear most often: why not just get the naturally aspirated 6.4L instead? These two engines are built for different jobs. The 6.4L is a workhorse. It’s available in heavy-duty trucks, it’s simpler to maintain, and it’s easier on your fuel budget. The 6.2L is a performance engine that happens to live in a truck body sometimes. If you need towing capacity, heavy-duty use, and lower running costs, the 6.4L is the smarter pick. If you want a truck that can outrun sports cars off the line, nothing else in Chrysler’s lineup competes with the 6.2L.

These two engines also never really competed for the same buyer. The 6.4L lives in heavy-duty 2500 and 3500 trucks. The 6.2L was reserved for the half-ton TRX. Different trucks, different jobs. Our real-world fuel numbers from a 6.4L-powered Power Wagon give a good sense of what to expect if the 6.4L fits your needs better.

Bottom Line

The 6.2L HEMI was never meant to be subtle. It’s a brute-force answer to a simple question: how much power can a pushrod V8 make before something breaks? For most owners who stick with stock or mild bolt-ons, the answer is: not much breaks. If you want big numbers and don’t mind paying for them, at the pump now and maybe at the shop later, this engine still delivers exactly what it promises.