The 24-valve Cummins engine refers primarily to the 5.9L and 6.7L inline-six turbo diesel engines used in Dodge Ram trucks and other applications. These engines are known for their durability, power, and popularity among diesel enthusiasts. Here’s a breakdown:
In this article:
- What is a 24 valves Cummins Engine?
- What is a cummins ISB(24 valve)?
- 24-Valve Cummins Overview:
- Generations and Key Differences:
- Why 24 Valves Matter:
- 🛠️ Popular Uses
- Are 24V Cummins still a good engine?
- How much power does a 24V Cummins make?
- What are some common problems with a 24-valve Cummins Engine?
- FAQ Section:
What is a 24 valves Cummins Engine?
A 24-valve Cummins engine is a turbocharged inline-six diesel engine with four valves per cylinder, totaling 24 valves. It offers improved airflow and efficiency over the earlier 12-valve version. Commonly found in Dodge Ram trucks, it’s known for durability, towing power, and tunability.
What is a cummins ISB(24 valve)?
The Cummins ISB (24-valve) is a turbocharged inline-6 diesel engine from Cummins’ Interact System B series. It features 24 valves (4 per cylinder) for better airflow, fuel efficiency, and emissions control. Commonly found in Dodge Ram trucks (1998.5–present), it’s known for reliability and strong torque output.
24-Valve Cummins Overview:
Engine Type:
- Inline-6 (I6) Turbo Diesel
- Valvetrain: 4 valves per cylinder × 6 cylinders = 24 valves
Generations and Key Differences:
1. 5.9L 24-Valve Cummins (1998.5–2007):
Commonly known as:
- ISB 5.9 (for “Interact System B”)
🔹 Features:
- Introduced in 1998.5, replacing the earlier 12-valve 5.9L.
- Uses an electronic VP44 injection pump (1998.5–2002)
- Switched to Common Rail Fuel Injection (2003–2007)
- Horsepower: ~235–325 hp
- Torque: ~460–610 lb-ft
- Known for a balance of performance and reliability.
2. 6.7L 24-Valve Cummins (2007.5–present)
Commonly known as:
- ISB 6.7
🔹 Features:
- Increased displacement for emissions and power.
- Common rail injection.
- Equipped with EGR, DPF, and later SCR for emissions.
- Integrated exhaust brake (from factory).
- Horsepower: ~350–420+ hp
- Torque: ~650–1,075 lb-ft (varies by year/model)
- Modern versions support high towing and payload capacities.
Why 24 Valves Matter:
- More valves = better airflow, resulting in:
- Improved efficiency
- Higher power output
- Cleaner emissions (especially in common rail versions)
🛠️ Popular Uses
- Dodge/Ram 2500, 3500, 4500, 5500
- School buses
- Medium-duty trucks
- Industrial and agricultural machinery
Are 24V Cummins still a good engine?
Yes, 24-valve Cummins engines are still considered very good engines, especially for those seeking durability, torque, and tunability.
Also Read: Why 24 valve cummins engine is best.
How much power does a 24V Cummins make?
The power output of a 24-valve Cummins engine depends on the engine model year and configuration. Here’s a breakdown:
🔧 5.9L 24-Valve Cummins (1998.5–2007)
📌 1998.5–2002 (VP44 Injection Pump):
- Horsepower: 215–245 hp
- Torque: 420–505 lb-ft
📌 2003–2007 (Common Rail Injection):
- Horsepower: 235–325 hp
- Torque: 460–610 lb-ft
🔧 6.7L 24-Valve Cummins (2007.5–Present)
- Horsepower: 350–420+ hp (varies by year and tuning)
- Torque: 610–1,075 lb-ft (newest high-output models)
However With performance upgrades (tuning, injectors, turbo, etc.), both 5.9L and 6.7L versions can exceed:
Torque: 1,000–2,000+ lb-ft
Horsepower: 500–1,000+ hp
What are some common problems with a 24-valve Cummins Engine?
- VP44 or injector failures
- Weak lift pump
- EGR/DPF problems (6.7L)
- Head gasket issues (tuned engines)
Also Read: Common problems with 24 valve cummins engine in detail.
Also Read: Rebuilding 24 valves cummins engine.
FAQ Section:
What is a 24-valve Cummins engine?
A turbocharged inline-6 diesel engine with 4 valves per cylinder, totaling 24 valves.
What vehicles use the 24V Cummins?
Primarily Dodge/Ram 2500 and 3500 trucks from 1998.5 to present.
What displacement is the 24-valve Cummins?
Either 5.9L or 6.7L, depending on the model year.
What does “ISB” stand for?
Interact System B – Cummins’ designation for electronic-controlled B-series engines.
Is the 24V Cummins turbocharged?
Yes, all 24-valve Cummins engines are factory turbocharged.
How much horsepower does a 24V Cummins make?
Between 215–420+ hp depending on year and model.
How much torque does it produce?
Ranges from 420–1,075 lb-ft depending on model and year.
Is the 24V Cummins good for towing?
Yes, it’s excellent for towing due to its high torque and durability.
Can it be tuned for more power?
Yes, both 5.9L and 6.7L models are highly tunable with aftermarket support.
How long does a 24V Cummins last?
With maintenance, 400,000+ miles is common.
What are common problems with the 5.9L 24V?
VP44 pump failure, lift pump issues, and injector problems.
What problems occur in the 6.7L version?
Mainly EGR/DPF issues, turbo actuator failures, and head gasket leaks.
Does the 24V Cummins have a timing belt or chain?
It uses timing gears, which are very reliable.
Is the 24V more reliable than the 12V Cummins?
More efficient and powerful, but the 12V is simpler and sometimes more durable.
Is the VP44 reliable?
Only if supported by a strong lift pump; otherwise, it often fails prematurely.
How often should oil be changed?
Typically every 5,000–7,500 miles, depending on use.
What fuel does it use?
#2 Ultra-Low Sulfur Diesel (ULSD).
Can you delete the emissions on the 6.7L?
Technically yes, but illegal in most places and not recommended.
What kind of transmission is commonly paired with it?
Usually the 47RE, 48RE, or 68RFE automatics, or NV4500/NV5600 manuals.
Is the 24V Cummins worth buying today?
Yes, especially the 2003–2007 5.9L common rail models for a mix of power and reliability.
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