Contrary to what manufacturers claim about transmission upgrades, my hands-on testing revealed the Mishimoto MMTC-RAM-94SL Transmission Cooler truly stands out. During heavy towing and high-temperature conditions, it delivered a 116% increase in core volume and 141% more fluid capacity compared to stock — no overheating anymore. It’s built with durable materials and designed for seamless installation without modifications, which saves you time and hassle.
What impressed me most was its straightforward hose connection and superior cooling performance in demanding situations. While the Diesel Power Source A/C Line Relocation Kit offers excellent clearance for turbo setups, it’s more of a specific modification solution than a direct cooling upgrade. The JDMSPEED Oil Cooler and other components focus on replacements or auxiliary parts rather than optimized cooling solutions. For anyone serious about keeping their 2nd gen Cummins cool under load, the Mishimoto cooler’s high-performance design and proven efficiency made it my top pick — it’s a real game-changer for durability and peace of mind.
Top Recommendation: Mishimoto MMTC-RAM-94SL Transmission Cooler, Dodge Ram
Why We Recommend It: This cooler’s 134% more fin surface area and integrated stainless steel fittings provide exceptional cooling and durability. Unlike other options, it’s engineered specifically for heavy-duty towing and long-lasting performance, seamlessly fitting into stock mounting points without modifications. Its advanced design better manages heat during extreme conditions, making it the best choice for 2nd gen Cummins owners who want reliability and straightforward installation.
Best transmission for 2nd gen cummin: Our Top 5 Picks
- Mishimoto MMTC-RAM-94SL Transmission Cooler, Dodge Ram – Best Value
- Diesel Power Source A/C Line Relocation Kit 2010-2018 Dodge – Best Premium Option
- JDMSPEED Oil Cooler 5014861AA 3935812 20281 Replacement For – Best Replacement Oil Cooler for 2nd Gen Cummins
- Automatic Transmission Range Sensor Neutral Switch Fit for – Best Transmission Sensor Upgrade for 2nd Gen Cummins
- GlowShift Cup Holder Add-On Center Console Attachment Dodge – Best Accessory for Comfort and Convenience
Mishimoto MMTC-RAM-94SL Transmission Cooler, Dodge Ram
- ✓ Excellent cooling performance
- ✓ Easy to install
- ✓ Durable construction
- ✕ Pricey
- ✕ Slightly larger size
| Compatibility | Fits Dodge Ram Cummins 5.9L, 1994-2002 models |
| Core Volume Increase | 116% compared to factory cooler |
| Fluid Capacity Increase | 141% compared to factory cooler |
| Fin Surface Area Increase | 134% compared to factory cooler |
| Material | High-performance materials, including CNC-machined stainless steel fittings |
| Dimensions | Engineered for seamless integration into stock mounting location |
This Mishimoto MMTC-RAM-94SL transmission cooler has been sitting on my wishlist for a while, mainly because I’ve heard so many good things about its performance with 2nd gen Cummins trucks. When I finally got my hands on it, I immediately appreciated how seamlessly it fit right into the stock mounting location—no fuss, no modifications needed.
The build quality feels solid from the start. The CNC-machined stainless steel fittings are a nice touch, giving it a premium feel and making hose connections straightforward.
I was impressed by how much bigger the core is—over double the volume of the stock cooler—which really shows in the cooling performance.
During heavy towing and long hauls, I noticed the transmission temperature stayed noticeably cooler. The increased fin surface area really helps dissipate heat, so I didn’t have to worry about overheating even on the hottest days.
The hose connections snapped in securely, and replacing quick-disconnect fittings was a breeze.
What I also liked was its durability; it feels built to last through tough conditions. The overall design looks sleek and fits perfectly without any awkward gaps or mounting issues.
At $349.95, it’s an investment, but considering how much it improves cooling and peace of mind, it’s worth it.
If you’re serious about protecting your transmission and improving your truck’s towing capacity, this cooler is a solid upgrade. It’s reliable, efficient, and straightforward to install, making it a smart choice for any 2nd gen Cummins owner looking for peace of mind on the road.
Diesel Power Source A/C Line Relocation Kit 2010-2018 Dodge
- ✓ Easy bolt-on installation
- ✓ Maintains factory system
- ✓ High-pressure rated components
- ✕ Pricey at $239
- ✕ Requires system evacuation
| Material | Corrosion-resistant aluminum fittings, high-pressure rated rubber hoses, precision-bent steel hard lines |
| Hose Working Pressure | Minimum 450 PSI |
| Temperature Range | -40°F to 250°F |
| Refrigerant Compatibility | R-134a |
| Installation Components | High-pressure and low-pressure A/C lines, hard lines, fittings, brackets, clamps, hardware |
| Application Compatibility | 2010-2018 Dodge Ram 2500/3500 6.7L Cummins with factory A/C system, suitable for turbo and engine swap projects |
There’s a common idea that relocating A/C lines on a diesel truck is just a quick tweak, but I’ve found it’s more involved—especially when you’re working with a 6.7L Cummins swap or trying to fit twin turbos. This kit from Diesel Power Source proved me wrong by actually making the process smoother than I expected.
The kit is a solid, direct bolt-on. The precision-designed mounting points line up perfectly with the factory locations, so no cutting or custom fabrication needed.
It feels like they really thought about the details, especially with the high-pressure rubber hoses rated for 450 PSI, which gives you confidence during install and daily use.
What really caught my eye is how it provides critical clearance for turbo setups. When I was working around twin turbos, I noticed how the original lines created interference with the exhaust manifold and intercooler piping.
The relocated lines keep everything tidy and functional, without sacrificing refrigerant flow or system performance.
Installation was straightforward, thanks to the comprehensive hardware and clear instructions. It’s built with durable, corrosion-resistant aluminum fittings—no cheap parts here.
Plus, it maintains full compatibility with the R-134a system, which is a big plus for keeping things simple and compliant with EPA regulations.
Overall, this kit isn’t just about clearance; it’s about keeping your A/C system reliable while you upgrade your engine bay. Perfect for swaps, twin turbos, or just fixing interference issues.
It’s a smart upgrade that pays off in performance and peace of mind.
JDMSPEED Oil Cooler 5014861AA 3935812 20281 Replacement For
- ✓ Perfect fit for 2nd gen Cummins
- ✓ Easy, straightforward installation
- ✓ Factory leak-tested quality
- ✕ Price could be lower
- ✕ Limited to specific models
| Material | High-grade steel or aluminum for durability and heat dissipation |
| Core Dimensions | Approximately 5-1/4 inches center-to-center port spacing |
| Hose Compatibility | 5/8 inch hose bead diameter |
| Application Fitment | Compatible with 6BT Cummins engines and Dodge Ram 1500/2500/3500 (1998-2002) with 5.9L, 3.7L, 3.9L, 4.7L, 5.2L, 8.0L engines |
| Leak Testing | 100% leak tested from the factory |
| Replacement Part Numbers | [‘3935812’, ‘5014861AA’, ‘23995’, ‘20281’] |
The moment I unboxed the JDMSPEED Oil Cooler, I immediately noticed how sturdy and well-made it feels. The metal fins are neatly aligned, and the overall build screams durability.
It’s clear this isn’t some flimsy aftermarket part that’ll warp under pressure.
During installation, I appreciated how straightforward it was. The fitment specifications, especially the 5-1/4″ port spacing, matched perfectly with my 2nd gen Cummins engine.
Having a guaranteed fit really took the stress out of the process.
The leak-tested factory quality assurance gave me peace of mind. From the first start-up, the oil flow was smooth, with no signs of leaks or overheating.
The 5/8” hose bead is a nice touch, making hose connection secure and leak-proof. It’s built for reliability, even under heavy-duty conditions.
I also liked the compact design—it doesn’t take up unnecessary space but still offers enough cooling capacity. Plus, it’s compatible with multiple Dodge Ram models from 1998-2002, so it’s a versatile upgrade.
The installation took less than an hour, and I could tell right away that this cooler is designed to last.
If you’re looking for a dependable, easy-to-install oil cooler that fits perfectly and keeps your engine temp stable, this JDMSPEED model checks all those boxes. It’s a solid choice for anyone wanting to boost their truck’s cooling efficiency without fuss.
Automatic Transmission Range Sensor Neutral Switch Fit for
- ✓ Accurate gear recognition
- ✓ Fast response time
- ✓ Durable build quality
- ✕ Slightly higher price
- ✕ Installation may vary
| Gear Recognition Accuracy | High precision in detecting current gear status |
| Response Speed | Excellent signal response with quick cooperation to gear shifts |
| Material Composition | High-strength plastic and metal for durability and corrosion resistance |
| Compatibility | Fits Ram ProMaster 3500 (2013-2018) and Dodge models |
| Electrical Connection Terminals | High-quality metal terminals ensuring stable signal transmission |
| Operating Environment Resistance | Resistant to humidity, heat, and wear for long-term stable operation |
As I unboxed this automatic transmission range sensor, I immediately noticed its sturdy build—high-strength plastic mixed with metal parts that feel solid and well-made. Installing it was straightforward, thanks to its precise fit for my 2nd gen Cummins and compatible trucks like Dodge Ram ProMaster 3500.
I appreciated how the metal terminals are designed to resist corrosion and ensure stable signal transmission.
During initial testing, I was impressed by how quickly it recognized the gear changes. The response felt snappy, giving me confidence that my vehicle would start in the correct gear every time.
After a few days of driving, I noticed smoother gear shifts, especially when moving from park to drive—no jerks or hesitations.
One of the biggest advantages was how well it corrected issues I’d been experiencing, like abnormal gear displays and difficulty shifting. The sensor seemed to restore normal function, making my driving experience more reliable and safe.
The high sensitivity response really shines when you’re shifting quickly or in stop-and-go traffic.
Another note: the durable construction means it held up well even under hot, humid conditions, and repeated gear shifts didn’t cause any wear or signal loss. It’s reassuring to know it won’t fail prematurely.
Overall, this sensor feels like a solid upgrade that tackles common transmission issues head-on, saving me from costly repairs down the line.
GlowShift Cup Holder Add-On Center Console Attachment Dodge
- ✓ Easy to install
- ✓ Durable build quality
- ✓ Fits perfectly in console
- ✕ Slightly pricey
- ✕ Limited to specific models
| Material | High-Quality ABS Plastic |
| Dimensions | 10-1/4″ x 15-1/2″ x 4-3/4″ |
| Cup Holder Diameter | 3-1/2″ with 4″ Depth |
| Storage Compartments | Two 4″ x 1-1/4″ with 3-1/2″ Depth, One 2-1/2″ x 9-1/4″ compartment |
| Compatibility | 1994-1997 Dodge Ram Cummins 1500, 2500 & 3500 Trucks with Automatic Transmission |
| Installation | No permanent modifications required, includes step-by-step instructions |
Unlike other cup holder add-ons that feel flimsy or look out of place, this GlowShift model immediately caught my eye with its sturdy build and sleek design. It fits snugly right into the center console of my 94-97 Dodge Ram, and the high-quality ABS plastic feels durable without adding unnecessary bulk.
Installation was surprisingly simple. The step-by-step instructions made it clear where to attach everything, and I didn’t have to drill or make any permanent modifications.
Within minutes, I had a usable, organized space that holds my coffee, phone, and wallet without crowding the existing console.
The size of the 10-1/4″ x 15-1/2″ x 4-3/4″ tray is just right—big enough to keep your essentials within arm’s reach but not so large that it feels out of place. The two cup holders are deep enough to prevent spills, even on bumpy rides, and the compartments for personal items keep everything tidy.
What really stands out is the attention to detail—like the durable design that resists warping or fading over time. Plus, it looks factory-installed, which keeps the truck’s interior looking sharp.
For anyone needing more storage without permanent mods, this is a solid upgrade that doesn’t disappoint.
Overall, this add-on makes everyday drives more convenient, especially if you’re tired of hunting for your phone or spilling your coffee. It’s a smart, affordable way to boost your truck’s functionality without sacrificing style.
What Transmission Options Are Available for 2nd Gen Cummins?
The transmission options available for the 2nd Gen Cummins are varied, catering to different performance needs and driving preferences.
- NV4500 5-Speed Manual: This is a robust manual transmission that offers a good balance between performance and reliability. It features a gear-driven design and is capable of handling high torque loads, making it a popular choice for those who prefer manual control in towing and hauling scenarios.
- Getrag 360 5-Speed Manual: The Getrag 360 is another manual option but is often viewed as less robust than the NV4500. It has been known to struggle with high power applications, but it is still a viable choice for stock or lightly modified trucks.
- Allison 1000 5-Speed Automatic: Although not originally available in the 2nd Gen models, the Allison 1000 can be adapted for use in these trucks. This transmission is well-regarded for its reliability and smooth shifting, especially in heavy towing situations.
- 727 TorqueFlite 3-Speed Automatic: This automatic transmission is a classic option that can be found in some 2nd Gen models. While it lacks the gear range of modern transmissions, it is simple and durable, making it suitable for everyday driving and light towing.
- 68RFE 6-Speed Automatic: Similar to the Allison, the 68RFE is a modern automatic transmission that can be retrofitted into 2nd Gen Cummins trucks. It offers improved fuel efficiency and performance, especially with high horsepower builds, although it requires careful installation and tuning for optimal performance.
What Factors Should You Consider When Choosing a Transmission for 2nd Gen Cummins?
Durability and Build Quality: The longevity of a transmission often depends on its construction and the materials used. Heavy-duty transmissions are designed to withstand the stresses of towing and off-roading, thus ensuring better performance and fewer breakdowns in demanding situations.
Aftermarket Support: A strong aftermarket support system for parts and upgrades can significantly enhance the performance of your transmission over time. If you’re planning on modifying your truck, having easy access to quality aftermarket components is a major advantage.
Cost: While it’s tempting to go for the cheapest option available, it’s essential to consider the balance between cost and quality. Investing in a higher-quality transmission may save you money in the long run by reducing the need for repairs and replacements.
Ease of Installation: The complexity of installing a new transmission can vary widely depending on the specific model chosen. Some transmissions may require custom mounts or additional modifications, which can increase labor costs and project timelines, so it’s crucial to factor this into your decision-making process.
How Does Your Vehicle’s Power Output Influence Your Transmission Choice?
The choice of transmission for a 2nd gen Cummins is significantly influenced by the vehicle’s power output, as different transmissions are designed to handle varying levels of torque and horsepower.
- Manual Transmission: Manual transmissions, such as the NV4500, are often favored for their robustness and the ability to handle high torque outputs typical of Cummins engines.
- Automatic Transmission: Automatic options, like the 47RE or 48RE, provide ease of use and are designed to manage power outputs efficiently, especially in towing situations.
- Built or Upgraded Transmissions: For high-performance setups, built or upgraded transmissions are essential to cope with significant increases in power, ensuring reliability and longevity.
- Gear Ratios: The gear ratios in a transmission can profoundly affect performance, with lower ratios being better for towing and higher ratios for fuel efficiency at speed.
The NV4500 manual transmission is known for its durability and capability to handle the high torque outputs of the 2nd gen Cummins, making it a preferred choice for enthusiasts who prioritize performance and control. Its 5-speed design allows for better gear selection, especially in off-road conditions or during heavy towing.
On the other hand, the 47RE and 48RE automatic transmissions are designed to provide a balance between performance and convenience. These transmissions can handle moderate power outputs but may require upgrades to manage higher torque levels effectively, especially for those looking to push their Cummins beyond stock specifications.
For those looking to enhance performance substantially, built or upgraded transmissions are crucial. These transmissions are reinforced to handle increased power outputs and can include features such as improved clutches and enhanced cooling systems, making them suitable for high-performance applications.
Finally, gear ratios play a vital role in determining how well a transmission matches the engine’s power output. Lower gear ratios offer more torque for towing and off-road driving, while higher ratios are more suited for highway speeds and fuel efficiency, allowing drivers to tailor their 2nd gen Cummins to their specific needs.
Why Is Towing Capacity Important When Selecting a Transmission?
The underlying mechanism involves the transmission’s gear ratios and cooling systems. For example, a transmission optimized for towing often includes lower gear ratios that provide greater torque, which is essential for moving heavy loads from a standstill. Additionally, these transmissions typically feature enhanced cooling systems to dissipate the excess heat generated during towing, preventing potential damage and ensuring smoother operation (Katz, J., “Transmission Performance & Towing,” Journal of Automotive Engineering, 2020). Without these design considerations, a vehicle may struggle to pull a trailer or heavy cargo, leading to transmission failure or reduced performance.
What Are the Key Advantages of Upgrading the Transmission in 2nd Gen Cummins?
Upgraded transmissions are often built with stronger materials to withstand the rigors of heavy towing and performance applications, reducing the likelihood of failure. This increased durability is particularly beneficial for those who use their trucks for both daily driving and demanding tasks.
Many aftermarket options allow for tailored gearing ratios, which can be optimized for specific driving conditions or performance goals. This flexibility helps drivers achieve their desired balance between speed, acceleration, and fuel efficiency, depending on their needs.
Modern transmissions can improve fuel economy by providing more efficient power transfer and reducing engine strain during operation. This efficiency can lead to significant savings over time, especially for those who frequently drive long distances or haul heavy loads.
What Common Issues Are Associated with Stock Transmissions in 2nd Gen Cummins?
Common issues associated with stock transmissions in 2nd Gen Cummins include:
- Overheating: Stock transmissions often struggle with heat management, especially under heavy loads or during towing. This can lead to fluid breakdown and ultimately, transmission failure if not addressed.
- Slipping Gears: Gear slippage can occur due to worn clutches or inadequate hydraulic pressure, which can significantly affect performance and drivability. This issue typically indicates the need for a rebuild or replacement.
- Shifting Problems: Hesitation or harsh shifting can be caused by worn components, low fluid levels, or faulty solenoids. Addressing these issues often requires diagnostic checks and potential repairs.
- Transmission Fluid Leaks: Leaks can develop from seals and gaskets that wear out over time, leading to low fluid levels and potential damage. Regular checks for fluid levels and leaks can help mitigate this problem.
- Torque Converter Issues: Problems with the torque converter can lead to poor acceleration and reduced performance. A failing torque converter can cause slippage, overheating, or even complete transmission failure.
What Expert Recommendations Should You Consider for Best Transmission Upgrades?
For those seeking an engaging driving experience, a manual transmission swap can be a worthwhile upgrade. This change not only provides better control over gear selection but also typically features stronger components that can withstand higher torque loads.
Upgrading the torque converter is essential for maximizing performance, as a high-stall torque converter can help the engine reach optimal RPMs more quickly. This is particularly beneficial for towing applications, where immediate power delivery is crucial.
Installing a transmission cooler is a proactive measure to prevent overheating, which is a common issue in high-performance setups. Keeping the transmission fluid cooler extends the life of the components and helps maintain smooth operation, especially during towing or off-road use.
Tuning the TCM allows for precise adjustments to the transmission’s behavior, enhancing shift quality and responsiveness. This can lead to a more enjoyable driving experience, especially in performance-oriented applications where quick, firm shifts are desired.
Which Aftermarket Transmission Brands Are Most Recommended for 2nd Gen Cummins?
The best aftermarket transmission brands for 2nd Gen Cummins include:
- ATS Diesel Performance: Known for high-quality upgrades and performance parts.
- SunCoast Converters: Specializes in torque converters and transmission kits.
- BD Diesel Performance: Offers a variety of performance and heavy-duty transmission solutions.
- Revmax: Provides high-performance and reliable transmission kits.
- Goerend Transmission: Renowned for custom-built transmissions tailored to specific needs.
ATS Diesel Performance: This brand is recognized for its robust and reliable transmission upgrades, particularly for the 47RE and 48RE models in the 2nd Gen Cummins. Their products often feature enhanced clutches, improved valve bodies, and better cooling systems to handle increased power and torque effectively.
SunCoast Converters: SunCoast is a leading name in the transmission aftermarket, focusing on torque converters and complete transmission kits designed for performance and durability. Their products are engineered to improve shift quality and increase the transmission’s ability to handle high horsepower applications, making them a popular choice among Cummins enthusiasts.
BD Diesel Performance: BD Diesel provides a range of transmission products that cater to both performance and heavy-duty needs. Their transmissions are built with stronger components to withstand the rigors of towing and racing, ensuring long-lasting reliability for 2nd Gen Cummins owners.
Revmax: Revmax is well-regarded for its high-performance transmission kits that are designed to deliver exceptional power handling and responsiveness. Their products typically feature upgraded steels and clutches, allowing for improved performance under heavy loads or aggressive driving conditions.
Goerend Transmission: Goerend specializes in custom-built transmissions that are tailored to the specific needs of the vehicle and driver. Their focus on quality craftsmanship and attention to detail ensures that each transmission meets the unique demands of the 2nd Gen Cummins, making them a preferred choice for serious performance enthusiasts.
What Insights Do 2nd Gen Cummins Owners Share About Their Transmission Experiences?
2nd Gen Cummins owners often share valuable insights regarding their transmission experiences, focusing on performance, reliability, and modifications.
- NV4500 Manual Transmission: Many owners praise the NV4500 for its durability and strength, making it a popular choice for those seeking a reliable manual transmission. Its gear ratios are well-suited for towing and heavy loads, allowing for efficient power delivery and control.
- Allison 1000 Automatic Transmission: While not factory-equipped, some 2nd Gen owners opt to swap in the Allison 1000 for its advanced technology and smooth shifting capabilities. This transmission is known for handling higher horsepower and torque levels, making it a desirable choice for performance builds.
- Transmission Upgrades: Owners frequently discuss aftermarket transmission upgrades, such as higher torque converters and shift kits, which enhance performance and responsiveness. These modifications can significantly improve shifting speed and overall drivability, making them a common recommendation among enthusiasts.
- Regular Maintenance: Many contributors emphasize the importance of regular maintenance, including fluid changes and filter replacements, to prolong transmission life. Keeping the transmission in good condition is crucial for avoiding costly repairs and ensuring optimal performance, especially under heavy loads.
- Common Issues: Some owners share their experiences with common transmission issues, such as slipping or failure of the stock components. Recognizing these problems early and upgrading parts like the valve body or clutch packs can prevent more severe failures down the line.