A transfer case is an essential component of a truck. This is usually used on all four-wheel vehicles. It is associated with the front and back axles.
Transfer cases work by distributing power from the engine to each wheel. On a truck’s drivetrain system, this serves as the focal point. NP 231 and NP 242 are both transfer cases of the Jeep.
When it comes to the NP 231 vs. NP 242 conversation, both of these transfer cases are pretty different from each other. The first is a part-time transfer case, while the latter is full-time. The 242 has smaller power output, so it’s perfectly fitted for trail riding.
The main difference that stands out when it comes to both of these transfer cases is the full-time or part-time performance. Depending on your vehicle and axles( Detroit or Moog), you must decide which transfer case is the best for you.
NP 231 Overview
Blowing up the transfer case of a truck when you’re trailing or towing a camper can be a real hassle. The NP 231 is a component that belongs to the rear and front axle and helps distribute power to all the wheels equally.
This type of transfer case can be seen in many models of vehicles like Peterbilt 378 or 379, especially among the new ones. This includes brands like Jeep and Dodge.

NP 231 has a good name in the community for several reasons. The first case would be its superb build quality. The NP 231 is manufactured as chain driven. The primary material for the case of the unit is aluminum which makes it light compared to other transfer boxes.
Despite its build quality, it faces some issues. When towed improperly, this transfer box is prone to exploding. This is because the innate build quality is not well suited for workloads that require high torque or oversized tires.
The NP 231 is a perfect unit to perform enhancements and upgrades. With enough modifications and upgrades, this unit’s longevity can be doubled.
One upgrade that the statistics suggest for most Jeep owners when using the NP 231 is the upgrade on the short shaft kit. This enables the owner to remove the driveshaft without any loss of fuel. It also allows an improved driveline angle.
NP 231 Pros And Cons
The 231 is an ultra-durable transfer case with good all-around performance in power and torque. They are also cheaper in comparison and versatile when it comes to upgrades.
Pros
● Aftermarket upgrades available
● Cheaper in comparison
● Durable build quality
● Large hubs plus chains
Cons
● Half-time isn’t always on 4×4
● Prone to exploding when towing the wrong load
The 231 is one of the most well-known transfer boxes among all the 4×4 systems we see. Ths transfer box is durable and has the power to back it up thanks to its planetary gear set. The most vital point of a 231 is its simplicity and versatility, making it easily interchangeable with other models.
NP 242 Overview
Jeep introduced NP 242 as a successor to NP 288. The 242 was first released back in 1987. It first appeared in commercially successful Jeep releases, such as The Cherokee (YJ), Wagoneer, wrangler CJ, TJ, and Comanche. It was intended to be used as a Selec-Trac and sport mode option.

The NP 242 has continued in the trend of chain-driven transfer cases. This version of 242 is more suited for high torque requiring workload and can output more power than the 231. The reason for higher torque output is thanks to six-pinion gears for the lower ranges.
The other main difference is the number at the end of each model – 1 for 231 and 2 for 242. This number signifies if the transfer case is full-time or half-time – 1 indicates half-time for NP 231, and 242 is full-time inversely.
Another thing to remember is that NP 242 is relatively uncommon compared to the 231. This makes it more expensive to buy at actual stores.
The build quality of NP 242 is reasonably good as well. It’s meant to be durable and sustaining. It is versatile, provides decent low range, and is well-fitted for any terrain you must trail over.
NP 242 Pros And Cons
The NP 242 transfer case is different from the 231 in the most basic sense that one is full-time. But beyond that, the 242 is more robust than a 231 regarding torque.
The 231 might be more durable and rugged if you add aftermarket enhancements, but the 242 is a great and versatile transfer case that can also withstand a lot of abuse.
Pros
● Has more torque
● Is full-time for a 4×4
● Can be driven smoothly in bad weather
● Can operate at higher angles
● Versatile, simple, and reliable
Cons
● Lays lower than the 231
● Lacks aftermarket support
● More expensive
Core Differences In NP 231 vs. NP 242 You Need To Know
The NP 242 and 231 are transfer boxes with some differences in performance and manufacturing qualities. The core differences between these transfer boxes would stand as follows:
● The difference in their base horsepower. 265 hp for the NP 231; on the other end, 243 hp for the 242
● NP 231 weighs less than 242. The difference is 15 pounds.
● 231 has a better ceiling regarding payload ability. It can carry two tons more in comparison.
● The 242 lacks additional locking hubs. The 231 is the only transfer case model with this feature
● The NP 242 includes more second and third-gear ratios. This isn’t available in the 231. This makes the 242 more expensive when compared to the 231.
● The 231 has more rpm capacity, clocked at 6800 rpm. On the other hand, the 242 limits at 6250.
● The engine capacity for NP 231 is 3.4 liters. For 242, it’s 4.6L. This makes the 231 engine lighter than the 242.
Comparison Table
NP 242 and NP231 are both pretty different. These are well-suited for driving in various weather conditions. Also, the fact that 231 is half-time compared to 242’s full-time 4×4 comes into play.
Sometimes NP231 is less suitable for dodge and shows eTorque issues. For your convenience, below is given a comparison table showcasing the fundamental differences between these transfer cases.
NP 231 | NP 242 | |
Horsepower | 265 Hp | 243 Hp |
Weight | 70 – 73 lbs | 88 lbs |
Payload capacity | 3 tons | 1-ton |
Torque | 600 lb-ft | 1486 lb-ft |
Upgradability | Available | Not available |
The 242 has better angles and more torque while performing full-time. On the other hand, 231 offers more freedom regarding aftermarket upgradeability. The 242 is also suited for different weather conditions.
Which One Should You Choose?
Now we conclude on the topic between two famous transfer cases, NP 231 vs. NP 242 – which one should you choose? Well, if you live in an area where it snows a lot and has rough weather conditions, you should choose the 242.
And if you want more durability and aftermarket enhancements on your transfer case, 231 should be the way to go!