Dodge Ram Cummins Horsepower & Torque

The 5.9 and 6.7 Cummins diesel engines are common options in Dodge and Ram trucks. These two engines have powered Dodge Ram trucks since 1989. Despite only two primary engine designs for a 30 year span there are many differences. Horsepower and torque can vary wildly by Cummins model year trucks. In this guide, we discuss Ram 5.9 & 6.7 Cummins horsepower and torque by model year along with some updates that support the increases.

Horsepower & Torque Timeline

We will split this up into two sections – one for the 5.9L Cummins and the other for the 6.7L Cummins turbodiesel. The 5.9 Cummins was available from 1989 to 2007. There are two primary variants known as the 12v and 24v Cummins engines. In 2007.5, the 6.7 diesel replaced the 5.9 engine. It’s still in production to date with up to a whopping 1,000 lb-ft.

Anyways, we’ll keep it there for now. Below each horsepower and torque timeline we will discuss a few of the primary updates that allow for power and/or torque increases by model year.

Dodge 5.9 Cummins HP & TQ By Model Year

Year	HP @ RPM	Torque @ RPM	Notes
1989	160hp @ 2,500	400 lb-ft @ 1,600	First year of 12v 5.9 Cummins
1990	160hp @ 2,500	400 lb-ft @ 1,600	NA
1991	160hp @ 2,500	400 lb-ft @ 1,600	Addition of intercooler
1992	160hp @ 2,500	400 lb-ft @ 1,600	NA
1993	160hp @ 2,500	400 lb-ft @ 1,600	NA
1994	160hp @ 2,500 (auto)     175hp @2,600 (man.)	400 lb-ft @ 1,500 (auto) 420 lb-ft @ 1,500 (man.)	P7100 Bosch pump
1995	160hp @ 2,500 (auto)     175hp @2,600 (man.)	400 lb-ft @ 1,500 (auto) 420 lb-ft @ 1,500 (man.)	NA
1996	180hp @ 2,500 (auto)     215hp @ 2,600 (man.)	420 lb-ft @ 1,500 (auto) 440 lb-ft @ 1,500 (man.)	NA
1997	180hp @ 2,500 (auto)     215hp @ 2,600 (man.)	420 lb-ft @ 1,500 (auto) 440 lb-ft @ 1,500 (man.)	NA
1998	180hp @ 2,500 (auto)     215hp @ 2,600 (man.)	420 lb-ft @ 1,500 (auto) 440 lb-ft @ 1,500 (man.)	Last year of 12v Cummins
1998.5	215hp @ 2,700 (auto)     235hp @ 2,700 (man.)	420 lb-ft @ 1,600 (auto) 460 lb-ft @ 1,600 (man.)	24v 5.9 Cummins introduced
1999	215hp @ 2,700 (auto)     235hp @ 2,700 (man.)	420 lb-ft @ 1,600 (auto) 460 lb-ft @ 1,600 (man.)	NA
2000	215hp @ 2,700 (auto)     235hp @ 2,700 (man.)	420 lb-ft @ 1,600 (auto) 460 lb-ft @ 1,600 (man.)	NA
2001	235hp @ 2,700 (auto)     245hp @ 2,900 (man.)	460 lb-ft @ 1,400 (auto) 505 lb-ft @ 1,400 (man)	High output engine introduced (only for NV5600 manual trans)
2002	235hp @ 2,700 (auto)     245hp @ 2,900 (man.)	460 lb-ft @ 1,400 (auto) 505 lb-ft @ 1,400 (man)	NA
2003	235hp @ 2,700 (auto)     305hp @ 2,900 (man.)	460 lb-ft @ 1,400 (auto) 555 lb-ft @ 1,400 (man)	Bosch common rail injection
2004	235hp @ 2,700 (auto)     325hp @ 2,900 (man.)	460 lb-ft @ 1,400 (auto) 600 lb-ft @ 1,600 (man)	NA
2005	325hp @ 2,900	610 lb-ft @ 1,600	NA
2006	325hp @ 2,900	610 lb-ft @ 1,600	NA
2007	325hp @ 2,900	610 lb-ft @ 1,600	Final year of the 5.9L Cummins

Manual vs Automatic Specs

As you’ll notice the manual transmission 5.9 Cummins diesel engines offer quite a bit more torque than the automatic. That’s especially true for the 24v Cummins where the manual is 40-140 lb-ft of torque higher. These are all the same engines for each specific model year. Higher torque is simply due to software changes for the manual versions.

In the past, automatics were a major limitation to torque. That’s the primary reason manual 5.9 Cummins deliver more torque. However, times have changed a lot since then. You’ll notice with the 6.7 Cummins the automatics are actually capable of a lot more torque than the manual options. Just an interesting side note.

12v to 24v Upgrade

The 12-valve versus 24-valve Cummins is a big topic when it comes to the Dodge Ram 5.9L diesel engine. Check out the previously linked article for more info. Here, we’ll simply lay out some of the basics.

24v Cummins engines came out in the middle of 1998 – hence the 1998.5 designation. As the name suggests it is a 24-valve engine instead of 12 valves. Even with its initial introduction power went up by 20hp and 20 lb-ft. By 2007, it offers an impressive 325 horsepower and 610 lb-ft.

A large part of the power improvements were due to the 4-valve per cylinder design and electronic engine management.

Other Major Changes

2001 saw the introduction of the high output 5.9 Cummins only available with the NV5600 6MT. This engine actually has some notable differences including:

• Higher compression
• Bosch fuel system updates
• Valve seat inserts
• Larger flywheel

A small compression increase and other updates allow the high output version to offer more power and torque. The fuel system notably receives updates to help flow more fuel for the power increase.

The next major change came in 2003 with the intro of Bosch high pressure common rail injection. Automatic transmission updates followed to allow the auto’s to produce similar horsepower and torque.

6.7 Cummins Horsepower & Torque Specs

Specs for 6.7 Cummins horsepower and torque by model year and transmission are as follows:

Auto vs Manual Transmissions

With the initial release of the 6.7L diesel the auto trans already has more 40 lb-ft higher torque. Eventually the manual transmission is able to peak at 660 lb-ft. By 2019 the manual would be 190 lb-ft behind the lower-end 68RFE automatic. As such, the manual was no longer offered after model year 2018.

It’s an unfortunate change for those who love manuals. However, automatic transmission technology is too good now days. Maybe the manual will reappear with the 6.7 Cummins one day. It’s hard to imagine that happening if the automatics continue to hold a 200-350+ lb-ft advantage, though.

Engine Updates

Notable changes to the 6.7 Cummins over the years include:

• 2010 – Powertrain control module (PCM) is added to control engine & trans
• 2011 – SCR emissions equipment now standard on chassis cab. New engine software
• 2013 – More software updates for power & torque improvements. SCR and DEF now standard on all Cummins 6.7L engines
• 2019 – Compact graphite iron block, new cams, updated cylinder head and valve-train, new turbo design, Bosch CP4.2 injection pump
• 2021 – Switch back to original Bosch CP3 injection pump due to high failures of CP4.2

Many updates prior to 2019 were fairly minor less the emissions changes. A lot of the 6.7 Cummins horsepower & torque improvements were due to transmissions and software changes. However, the large updates to the engine block, camshafts, valvetrain, cylinder head, and turbocharger came in 2019.

Summary

Cummins 5.9 & 6.7 turbodiesel engines are an awesome choice in Ram 2500/3500 trucks. This platform has come a long way since the initial release of the 5.9L engine. All the way from 400 lb-ft in the early days to a whopping 1,075 lb-ft of torque in 2021.

HP and torque changed a lot over the years. Many small improvements were from engine software updates, and other minor tweaks to support the new power output. One big consideration is the automatic vs manual Cummins diesel engines. With the 5.9 Cummins the manuals reigned supreme. However, manuals are no longer an option on the 2019+ 6.7L engine since they fell too far behind.

Nonetheless, these are all great engines that offer competitive horsepower and torque. It’s crazy to see the 1,000+ torque figure that seems standard now days with the proper transmission and truck.