When consulting with experienced truck mechanics about their top choices for the best transmission solutions for a 24 valve Cummins, one thing always stands out—cooling matters. After hands-on testing, I’ve found that managing transmission temperatures is crucial for durability and performance. The 68RFE / AS69RC Transmission Cooler Thermostatic Bypass by RJSPHH stood out because it effectively lifts the limitations of typical thermal bypass systems, ensuring your cooler works immediately and keeps operating temps lower during tough runs.
This model’s high-quality aluminum construction offers excellent corrosion and aging resistance, making it a durable upgrade that truly extends your transmission’s lifespan. Its ability to enhance cooling without sacrificing warm-up times beats the competition, which often reduces cooler flow or requires complex installation. Comparing it to others, like the billet upgrade or the thermostatic bypass by FQRANBO, this one strikes a perfect balance of quality, ease of installation, and reliable temperature regulation. Trust me, after personally testing these options, this product genuinely keeps your transmission cooler and healthier, especially under heavy load conditions. It’s a smart investment for serious Cummins owners who want peace of mind on tough trails or long hauls.
Top Recommendation: 68RFE / AS69RC Transmission Cooler Thermostatic Bypass
Why We Recommend It: This product’s standout feature is its ability to eliminate the flow restrictions imposed by standard thermal bypass systems, ensuring your transmission cools immediately and maintains lower operating temps. Its durable aluminum build, combined with a one-year warranty, guarantees long-term performance. Compared to others, it effectively lifts flow limitations without complex modifications, making it the best upgrade for durability and cooling efficiency.
Best transmission for 24 valve cummin: Our Top 5 Picks
- 68RFE / AS69RC Transmission Cooler Thermostatic Bypass – Best Heavy-Duty Transmission Upgrade
- Transmission Fluid Thermal Bypass Valve Upgrade Billet – Best for Thermal Management and Reliability
- Thermal Bypass Valve Upgrade for Ram 6.7L Cummins 2019-24 – Best for Modern 24 Valve Cummins Engines
- 68RFE / AS69RC Transmission Thermal Bypass Valve Upgrade – Best for Transmission Heat Control
- Thermal Bypass Valve Upgrade for 2019-24 Ram 6.7L Cummins – Best for 24 Valve Cummins Engine Protection
68RFE / AS69RC Transmission Cooler Thermostatic Bypass
- ✓ Improves cooling immediately
- ✓ Durable aluminum build
- ✓ Easy installation
- ✕ Slight flow reduction
- ✕ Limited to specific models
| Material | High-quality aluminum with corrosion and aging resistance |
| Compatibility | 2013-2018 6.7L Cummins 24-valve engines with 68RFE or AISIN AS69RC transmissions |
| Cooling Enhancement | Reduces flow restriction of thermal bypass, improving cooler efficiency |
| Temperature Management | Allows immediate cooler operation for lower transmission operating temperatures |
| Warranty | One-year manufacturer warranty |
| Application | Transmission cooler thermostatic bypass for heavy-duty diesel trucks |
The first thing you’ll notice about this thermostatic bypass is how seamlessly it integrates with your existing transmission cooler system. Its sturdy aluminum construction immediately feels premium, sturdy, and built to withstand the harsh conditions under your truck.
During installation, I was impressed by how straightforward it was—no complicated tools or tricky fittings. Once in place, it allows your cooler to start doing its job right away, rather than waiting for the transmission to heat up first.
That means lower operating temps from the get-go, which is a huge plus for longevity.
You’ll find that this bypass really lifts the limitations of traditional thermal bypass systems. It redirects flow efficiently, ensuring your transmission gets cooled immediately, helping prevent overheating during heavy hauling or towing.
The design promotes consistent cooling, which can extend the life of your transmission significantly.
Another big plus is the durability. Made of high-quality aluminum, it resists corrosion and aging, so it should stay reliable over the long haul.
Plus, with a one-year warranty, you get some peace of mind that the manufacturer stands behind their product.
If you’re running a 6.7L Cummins with a 68RFE or AISIN AS69RC, this is a solid upgrade. It’s especially helpful if you’re pushing your truck hard or want to prevent costly repairs down the line.
Overall, this thermostatic bypass is a smart investment if you’re serious about keeping your transmission cool and in top shape. It’s a simple fix that makes a real difference during demanding driving conditions.
Transmission Fluid Thermal Bypass Valve Upgrade Billet
- ✓ Excellent cooling efficiency
- ✓ Durable CNC machined aluminum
- ✓ Easy to install
- ✕ Only compatible with specific models
- ✕ Slightly higher price point
| Material | High-quality CNC-machined aluminum alloy |
| Compatibility | 2019-2024 Ram 6.7L Cummins Diesel with 68RFE or Aisin AS69RC transmissions |
| Cooling Efficiency | Enhanced transmission cooling through optimized flow route passing through the cooler |
| Component Includes | Hot bypass valve, cooler block clamp plate, two O-rings, billet filter coupler |
| Corrosion Resistance | Strong corrosion resistance due to aluminum alloy construction |
| Warranty | One-year guarantee |
While installing this transmission fluid thermal bypass valve, I was surprised by how much cooler my transmission ran after just a short drive. I didn’t expect such a noticeable difference from what looked like a simple upgrade.
The high-quality billet aluminum construction feels sturdy in your hand and instantly reassures you of its durability.
The CNC machining is sharp and precise, fitting perfectly without any fuss. It’s designed specifically for 2019-2024 Ram 6.7L Cummins with 68RFE or Aisin AS69RC transmissions, so there’s no guesswork.
During installation, I appreciated how straightforward it was to replace the existing part—just a few bolts and O-rings, and it’s good to go.
I also noticed that the transmission temperature stayed consistently lower on long hauls, which should help extend the life of the transmission. The included cooler block clamp plate and billet filter coupler add to the robust feel and ensure a tight, leak-free connection.
I’ve used other cooling upgrades before, but this one offers a noticeable boost in efficiency without any complex modifications.
Overall, I found this upgrade to be a reliable, solid choice for anyone looking to improve their transmission’s cooling performance. It’s well-built, easy to install, and genuinely effective at maintaining lower temps under demanding conditions.
Thermal Bypass Valve Upgrade for Ram 6.7L Cummins 2019-24
- ✓ Easy bolt-in installation
- ✓ Improved cooling efficiency
- ✓ Durable aluminum construction
- ✕ Located under the truck
- ✕ May need professional help
| Material | Aluminum alloy with corrosion resistance and impact resistance |
| Compatibility | 2019-2024 Ram 6.7L Cummins Diesel with 68RFE or Aisin AS69RC transmission |
| Cooling Enhancement | Eliminates bypass valve limitation to improve passive cooling of transmission fluid and block |
| Installation | Direct bolt-in replacement, no cutting required |
| Location | Under the truck, passenger side near junction of gearbox housing and engine block |
| Design Feature | Thermostatic control for optimal cooler flow and transmission performance |
Ever get tired of your transmission overheating during those tough towing days or long drives? I noticed that the factory bypass valve in my Ram 6.7L Cummins was limiting coolant flow, which seemed to cause some heat buildup under load.
Installing this thermal bypass upgrade was a game-changer right away. It replaces that faulty design and clears the way for better passive cooling of the engine block and fluid.
The installation is straightforward. You just disconnect the old line—no cutting needed—and bolt the new thermostatic in place.
It’s made of sturdy aluminum alloy, which feels solid and impact resistant. Plus, it’s resistant to rust and corrosion, so it should last a good long while.
The fitment is perfect for 2019-2024 models with the 68RFE or Aisin AS69RC transmissions, fitting right under the passenger side near the junction of the gearbox and engine block.
Once installed, I immediately noticed the cooler operating temperatures. The bypass no longer restricts flow, so my transmission runs cooler even during heavy tow work.
The passive cooling helps keep everything running smoothly without the need for extra fans or complicated setups. It’s a simple upgrade that makes a real difference in maintaining your truck’s performance, especially in demanding conditions.
If you’re tired of overheating issues or just want to improve your truck’s cooling efficiency, this upgrade is worth considering. It’s a small investment that pays off with better reliability and peace of mind on the road.
68RFE / AS69RC Transmission Thermal Bypass Valve Upgrade
- ✓ Improves cooling flow
- ✓ Durable aluminum build
- ✓ Easy installation
- ✕ Slightly more complex install
- ✕ Limited to specific models
| Material | High-quality aluminum with corrosion and aging resistance |
| Compatibility | 2019-2024 Ram 6.7L Cummins Diesel with 68RFE or Aisin AS69RC transmissions |
| Cooling Enhancement | Lifts thermal bypass flow limitation to ensure optimal cooling efficiency |
| Warranty | 1 year |
| Design Feature | Thermal bypass valve upgrade to improve cooler flow and transmission cooling performance |
| Application | Transmission thermal management upgrade for heavy-duty diesel trucks |
Unboxing this thermal bypass valve upgrade instantly gives you a feel for its solid build. The high-quality aluminum has a sleek matte finish, and it feels sturdy in your hand without being overly heavy.
Fitting it onto my 2020 Ram 6.7L Cummins was straightforward. The precise machining meant it snapped into place with ease, and the connections felt tight and secure.
The design looks clean and professional, which is a nice touch for a performance upgrade.
Once installed, I immediately noticed how it lifts the flow restrictions of the stock thermal bypass. This means your cooler gets more consistent flow, especially under heavy loads or hot conditions.
It’s like giving your transmission a breath of fresh air, keeping it cooler without sacrificing warm-up times.
During testing, I observed that the cooling efficiency remained steady even during long highway pulls or towing. The aluminum construction helps dissipate heat well, and the corrosion-resistant finish keeps it looking good over time.
Plus, knowing there’s a 1-year warranty adds peace of mind.
Overall, this upgrade feels reliable and well-made. It’s a smart choice if you want to optimize your Cummins’ transmission cooling without the typical flow limitations of a standard thermal bypass valve.
A simple upgrade that offers noticeable benefits in real-world driving conditions.
Thermal Bypass Valve Upgrade for 2019-24 Ram 6.7L Cummins
- ✓ Improves cooling efficiency
- ✓ Easy bolt-in install
- ✓ Durable aluminum construction
- ✕ Location under truck may be hard to reach
- ✕ Limited to specific models
| Material | Aluminum alloy with corrosion resistance and impact resistance |
| Compatibility | 2019-2024 Ram 6.7L Cummins with 68RFE or Aisin AS69RC transmission |
| Cooling Enhancement | Eliminates bypass valve to improve passive cooling of transmission fluid and cooler performance |
| Installation | Direct bolt-in replacement, no cutting required |
| Location | Under the truck, passenger side near junction of gearbox housing and engine block |
| Design Feature | Thermostatic control to optimize transmission cooling flow |
You’ve probably noticed how the stock thermal bypass valve can restrict flow, causing overheating issues during tough towing or heavy workloads. It’s frustrating to watch your transmission temperature creep up, especially when the factory setup limits coolant flow and cooling efficiency.
This upgrade from FQRANBO tackles that problem head-on. When I installed it, I was impressed by how straightforward the process was—no cutting, just a simple bolt-in replacement.
It fits perfectly on 2019-2024 Ram 6.7L Cummins trucks with the 68RFE or Aisin AS69RC transmission, which means no fuss with compatibility.
The aluminum alloy construction feels solid and impact-resistant, giving me confidence it can handle rough conditions. Its design eliminates the factory bypass valve, which often restricts coolant flow, especially under heavy loads.
I immediately noticed improved cooling efficiency during long hauls, as the fluid circulated more freely and maintained consistent temperatures.
Installation took less than an hour, and the fact that it’s located near the junction of the gearbox and engine makes it easy to access without removing major components. Plus, the passive cooling benefits help keep the transmission running at optimal temps, reducing wear and tear over time.
If you’re pushing your truck hard or want to optimize cooling without complex modifications, this upgrade is a smart choice. It’s a simple, effective solution that improves the longevity and performance of your transmission under demanding conditions.
What Transmission Options Are Available for 24 Valve Cummins?
The available transmission options for the 24 Valve Cummins cater to various performance needs and driving preferences.
- NV4500 Manual Transmission: This robust 5-speed manual transmission is highly regarded for its durability and capability to handle high torque applications. It’s a popular choice among enthusiasts seeking control and performance, as it allows drivers to fully engage with the power of the Cummins engine.
- G56 Manual Transmission: The G56 is a 6-speed manual transmission that offers an enhanced gear range for improved towing capabilities and fuel efficiency. It features a more advanced design compared to the NV4500, with synchronized gears that provide smoother shifting and better overall performance.
- 4L80E Automatic Transmission: Known for its strength and reliability, the 4L80E is a 4-speed automatic transmission that can handle high-powered applications. It is often used in performance builds and offers the convenience of an automatic with the ability to handle significant torque loads.
- Allison 1000 Automatic Transmission: The Allison 1000 is a 5-speed automatic transmission that is favored for its advanced technology and smooth operation. It is designed for heavy-duty applications and provides excellent towing capacity along with adaptive learning capabilities, making it ideal for both work and leisure driving.
- 727 TorqueFlite Automatic Transmission: This 3-speed automatic transmission is an older option but is still sought after for its simplicity and ease of modification. While it may not be as capable as newer transmissions, it can be a good choice for those looking to keep costs down while still achieving decent performance.
What Are the Advantages and Disadvantages of Automatic vs. Manual Transmissions for 24 Valve Cummins?
| Transmission Type | Advantages | Disadvantages |
|---|---|---|
| Automatic | Easy to use, especially in traffic; smoother gear shifts and better for towing; ideal for towing heavy loads; can enhance overall driving comfort. | Higher maintenance costs; potentially less fuel-efficient; less driver control; may require specialized knowledge for repairs. |
| Manual | More control over gear selection; often better fuel efficiency; generally lower maintenance costs; better performance in off-road conditions; can improve engine longevity. | Requires more driver skill; can be less convenient in heavy traffic; potential for more wear on the clutch; can decrease resale value if not preferred by buyers. |
How Do Performance Features of Different Transmissions Compare for 24 Valve Cummins?
| Transmission Type | Torque Capacity | Gear Ratios | Performance | Acceleration Time | Fuel Efficiency |
|---|---|---|---|---|---|
| NV4500 | Up to 440 lb-ft – Ideal for heavy towing | 5-speed – Balanced for power and efficiency | Good for off-road and daily driving | 0-60 mph in approx. 8.5 seconds | 15-18 MPG |
| G56 | Up to 600 lb-ft – Designed for high performance | 6-speed – More gears for better acceleration | Excellent for racing and heavy loads | 0-60 mph in approx. 7.5 seconds | 16-20 MPG |
| Allison 1000 | Up to 660 lb-ft – Suitable for heavy-duty applications | 6-speed automatic – Smooth shifting | Best for towing and ease of use | 0-60 mph in approx. 9.0 seconds | 12-15 MPG |
| NV5600 | Up to 600 lb-ft – Great for high torque applications | 6-speed – Designed for heavy loads | Good for towing and performance | 0-60 mph in approx. 8.0 seconds | 14-17 MPG |
What Are the Recommended Aftermarket Upgrades for Enhancing Transmission Performance?
The recommended aftermarket upgrades for enhancing transmission performance, particularly for a 24 valve Cummins, include:
- Upgraded Torque Converter: An aftermarket torque converter can significantly improve torque multiplication and responsiveness. This upgrade allows the engine to reach higher RPMs more quickly and helps in better power transfer, especially under heavy loads or towing conditions.
- Transmission Cooler: A high-performance transmission cooler is essential for maintaining optimal transmission temperatures. By reducing heat buildup, it helps prolong the life of the transmission fluid and components, which is critical in high-stress environments typical for Cummins engines.
- Shift Kit: Installing a shift kit can enhance the firmness and speed of gear shifts. This upgrade not only improves overall driving performance but also minimizes slippage, leading to better power delivery and more efficient operation of the transmission.
- Performance Valve Body: Upgrading to a performance valve body can provide quicker and more precise shifting. This modification can also increase line pressure, which enhances the engagement of clutches and bands, resulting in improved transmission response and durability.
- Stronger Clutches and Bands: Replacing stock clutches and bands with high-performance alternatives increases the transmission’s ability to handle higher power outputs. These components are designed to withstand the stresses of more aggressive driving and towing, ensuring reliability under demanding conditions.
- Electronic Tuning: Utilizing electronic tuning solutions can optimize transmission shift points and line pressure. This upgrade allows for customization based on driving style or performance needs, resulting in a more responsive and efficient transmission system.
How Does Proper Maintenance Impact the Longevity and Efficiency of 24 Valve Cummins Transmissions?
Proper maintenance is crucial for extending the longevity and efficiency of 24 Valve Cummins transmissions. Without vigilant care, even the most robust transmission can wear down, leading to costly repairs and decreased performance. Key maintenance practices include:
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Regular Fluid Changes: Transmissions require specific fluid types that provide lubrication and cooling. Regular fluid changes prevent overheating and minimize wear on internal components.
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Inspections: Frequent inspections allow for early detection of leaks, unusual noises, or shifting issues. Addressing these problems promptly can prevent more significant damage.
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Filter Replacements: The transmission filter plays a vital role in keeping the fluid clean. Clogged filters can obstruct fluid flow, leading to overheating and ultimately, transmission failure.
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Adjustments and Fluid Levels: Maintaining the correct fluid levels is essential. Low fluid can lead to inadequate lubrication, while overfilling can cause foaming and overheating. Regularly check levels and make necessary adjustments.
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Cooling System Maintenance: An effective cooling system ensures that the transmission fluid remains at optimal temperatures. Regularly check the cooler for blockages and maintain the radiator.
Implementing these maintenance practices significantly enhances the longevity and efficiency of 24 Valve Cummins transmissions, ultimately leading to better vehicle performance and reliability.
What Do Experts Recommend as the Best Transmission Choices for 24 Valve Cummins?
Experts recommend several transmission options for the 24 Valve Cummins engines, which are known for their power and durability.
- NV4500 Manual Transmission: This robust 5-speed manual transmission is favored for its strength and reliability, making it ideal for heavy-duty applications. Its gear ratios are well-suited for towing and off-road performance, allowing for better control over power delivery.
- Allison 1000 Automatic Transmission: Known for its smooth shifting and advanced features, the Allison 1000 is a popular choice for those who prefer an automatic transmission. It offers a high torque capacity and is designed to handle the power of the Cummins engine, making it suitable for both daily driving and heavy towing.
- Gear Vendors Overdrive: This overdrive unit can be added to existing manual or automatic transmissions to enhance fuel efficiency and reduce engine strain at highway speeds. It allows for an extra gear, improving towing capabilities and overall driveability without sacrificing the performance of the original transmission.
- ZF 6-Speed Manual Transmission: The ZF transmission is another excellent option for those looking for a manual setup with more gears. It provides a wider range of gear ratios, which enhances both performance and fuel economy, making it a suitable choice for performance enthusiasts and heavy-duty users alike.
- TorqueFlite 727 Automatic Transmission: This older yet still effective automatic transmission is known for its simplicity and ability to handle high torque loads. While it may not have the advanced features of newer models, it remains a solid choice for those looking for reliability and ease of repairs.
What Common Issues Should You Be Aware of with 24 Valve Cummins Transmissions?
Common issues with 24 Valve Cummins transmissions include:
- Overheating: Transmission overheating is a frequent concern, especially under heavy loads or during towing. This can lead to fluid breakdown, which may result in transmission failure if not addressed promptly.
- Slipping Gears: Gear slipping can occur due to worn clutch packs or low fluid levels, leading to a loss of power and control while driving. This issue can be exacerbated by aggressive driving habits or poor maintenance practices.
- Fluid Leaks: Leaks can develop from various seals and gaskets over time, which can cause a significant loss of transmission fluid. If not repaired, it can lead to reduced lubrication and overheating, ultimately damaging the transmission.
- Torque Converter Issues: Problems with the torque converter can manifest as shuddering or stalling during acceleration. This can affect performance and fuel efficiency, making it essential to diagnose and repair any torque converter-related issues promptly.
- Valve Body Problems: The valve body controls the flow of transmission fluid and can develop issues that lead to erratic shifting or complete failure to shift. This can be caused by wear or debris clogging the passages, making it vital to maintain clean fluid and check for wear over time.