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Car Buying Advice, Tips, and Reviews

A blue 2021 Ram 2500 is shown from the front towing a tractor.

Powering the Powerful 2021 Ram 2500

When you think of the words heavy-duty, you probably think of a truck that has the power and capability to do things that no other pickups could imagine doing. These are the monster trucks, the ones that are the stuff of nightmares for folks riding around in small subcompact cars. But did you ever stop to think of how these heavy-duty trucks get the power to tow large trailers and carry such heavy loads? Taking a look at the 2021 Ram 2500, you will see a heavy-duty truck that is built for those toughest jobs. But the key is what is going on inside that truck, located right behind its massive, aggressive front grille.

The 2021 Ram 2500 offers two different engines to choose from, which allows you the ability to decide on the one that works best for you and will give you the performance you desire in this heavy-duty truck. Whichever engine you choose, you are getting a rugged and powerful truck in the Ram 2500. You even have the option of the 2021 Ram 2500 Power Wagon 75th Anniversary Edition, built for off-road performance while paying homage to Ram’s legacy of great trucks.

8 Cylinders of Gasoline Power

The standard engine on the 2021 Ram 2500 truck is a 6.4-liter HEMI V8. This engine is paired with an 8HP75 8-speed automatic transmission to improve engine efficiency and give you greater control over the engine’s performance. This transmission has fully electronic operation with on-the-fly shift mapping, meaning that the shifts will be much smoother than you might expect on a heavy-duty truck.

The engine produces 410 horsepower while generating 429 pound-feet of torque. That is plenty for you to get the job done with your Ram 2500. Ram has chosen to use variable valve timing with Fuel Saver Technology cylinder deactivation for better performance while reducing emissions, which can often be a problem on heavy-duty trucks.

A blue 2021 Ram 2500 is shown from the side parked in a field at sunset.

6 Cylinders of Turbocharged Diesel Strength

Ram also offers a diesel engine option on the 2021 Ram 2500. This is a 6.7-liter Cummins Turbo Diesel I6 engine that comes paired with a 68RFE 6-speed automatic transmission. The design of this diesel engine is a pushrod 24-valve beast that produces 370 horsepower and generates an astounding 850 pound-feet of torque. That is the kind of torque that sets the 2021 Ram 2500 apart from other heavy-duty trucks in its class.

The decision to pair this engine with a 6-speed automatic transmission was a wise one on the part of Ram. The rugged 6-speed automatic transmission is electronically controlled and has been designed with gear ratios specially designed to get the most out of the 6.7-liter Cummins Turbo Diesel engine.

Acceleration Comparison

Let’s take a look at comparing the performance between these two engines on the 2021 Ram 2500 in a number of different criteria. The first is acceleration and speed. As you would probably expect, the Ram 2500 with the 6.4-liter HEMI V8 outperforms the 6.7-liter Cummins Turbo Diesel I6 in this area. However, the numbers may surprise you as they are closer than you may have expected.

Going from 0 to 60 miles per hour in your 2021 Ram 2500 with a 6.4-liter HEMI V-8 will take you about 7 seconds. While this won’t get folks to confuse your heavy-duty truck with a Dodge Charger muscle car, this is solid acceleration for a heavy-duty truck, so you won’t have to worry about getting off the light when you’re driving local roads. Surprisingly, the 2021 Ram 2500 with the 6.7-liter Cummins comes pretty close to matching that number, as it can go from 0 to 60 miles per hour in around 8 seconds. Most folks who have driven diesel trucks complain that they can be really sluggish off the light. However, the addition of a turbocharger gives you the horsepower you need as quickly as possible, getting your Ram 2500 moving faster than expected.

How about getting this truck into top gear? The Ram 2500 with the 6.4-liter HEMI V8 might be expected to be a bit faster than the one with a 6.7-liter Cummins Turbo Diesel I6. However, the truck is governed at 103 miles per hour regardless of which engine you choose. Still, unless you’re lucky enough to be driving on a freeway that’s not frequented by the highway patrol, either engine will be fine for any normal highway driving.

Towing Comparison

One of the biggest reasons to buy a heavy-duty truck is for towing trailers. No other pickup truck gives you the towing capability to match a heavy-duty model. This goes regardless of whether you are planning to use your 2021 Ram 2500 truck for business, pleasure, or a little bit of both. The good news is that both engines will provide you with plenty of strength for towing trailers. However, choosing to equip your Ram 2500 with a 6.7-liter Turbo Diesel will give you greater towing capacity than going with the 6.4-liter HEMI V8.

The maximum towing capacity of the 2021 Ram 2500 with the Turbo Diesel is 20,000 pounds. This is almost 2,500 pounds more than the capability of the same truck with the HEMI V8, which tops out at 17,540 pounds. No matter which cab configuration, trim, or drivetrain you choose, opting for the available Cummins I6 will allow you to tow heavier trailers.

You can see this across all trims. For example, if you choose a 2021 Ram 2500 Tradesman Crew Cab with rear-wheel drive and an 8-foot box, you will be able to tow up to 19,030 pounds with the Turbo Diesel. Choosing the exact same truck but with the HEMI V8 will allow you to tow up to 14,440 pounds. Similarly, The 2021 Ram 2500 Big Horn Mega Cab with four-wheel drive and a 6-foot 4-inch box can tow up to 13,970 pounds when equipped with the HEMI V8. This number increases to 15,700 pounds when you choose the available Turbo Diesel.

A blue 2021 Ram 2500 is shown from the front towing a tailor.

Payload Comparison

Another major reason for buying a heavy-duty truck is for carrying cargo in your pickup’s bed. Ram gives you a choice of two boxes on your 2021 Ram 2500: a 6-foot 4-inch standard bed and an 8-foot extended bed. The standard bed gives you a total of 57.5 cubic feet of space, while the extended bed has 74.7 cubic feet of cargo space.

Interestingly enough, the conventional gas engine on the Ram 2500 is better for carrying cargo than the available Turbo Diesel. This is because the smaller gasoline engine is lighter and uses up less of the truck’s maximum weight. When equipped with a 6.4-liter HEMI V8, the 2021 Ram 2500 can carry up to 4,010 pounds of payload. This number drops slightly to 3,160 pounds of payload when you choose the 6.7-liter Cummins I6.

Looking more closely, you can see that the Ram 2500 Tradesman Crew Cab with rear-wheel drive and an 8-foot box has a maximum payload capacity of 3,410 pounds when equipped with the HEMI V-8. The same truck with the Turbo Diesel can carry up to 2,500 pounds. This difference is also true for the 2021 Ram 2500 Big Horn Mega Cab with four-wheel drive and a 6-foot 4-inch box. When equipped with a HEMI V-8 engine, you can carry up to 2,940 pounds of cargo, while choosing the Turbo Diesel drops that number slightly to a 2,050-pound cargo capacity.

Price Comparison

One thing to consider is the pricing. In general, choosing to equip your 2021 Ram 2500 with an optional 6.7-liter Cummins Turbo Diesel will increase your price tag by about $10,000. You should keep in mind that the base MSRP on the 2021 Ram 2500 ranges from $35,425 for a Tradesman all the way up to $63,040 for a Limited. While the Cummins brings a lot of extra capability, that capability comes at a price.

Choosing the Right Truck

As with any other vehicle purchase, the key is to find the right truck for you. If you are looking to tow heavy equipment for work or a camper for pleasure, then you might consider buying the 2021 Ram 2500 with the 6.7-liter Cummins Turbo Diesel I6, as this will give you greater towing capability compared to the conventional gas engine. On the other hand, if you aren’t as interested in using your 2021 Ram 2500 for towing and are more concerned with payload, then choosing a model with the 6.4-liter HEMI V8 will allow you to carry more cargo than the Turbo Diesel. Finally, if your main consideration is price, then the HEMI V8 engine is your best choice. But no matter which engine you choose, you are getting a rugged, dependable heavy-duty truck that is built to do the job.