What transmission is a Ram 2500 with the 6.7 Cummins?

The Ram 2500 equipped with the 6.7-liter Cummins turbo diesel uses a six-speed automatic transmission built by Aisin. There is no factory manual option in the current lineup.

Current transmission pairing

Today’s Ram 2500 heavy-duty pickups with the 6.7L Cummins diesel are mated to a durable six-speed automatic transmission produced by Aisin Seiki. This pairing is designed to handle the torque and towing demands of a high-capacity diesel pickup, delivering reliable shifts under load and smoother operation for long drives and work duties.

The following summary provides quick context for what that automatic pairing means in practice:

• Type: 6-speed automatic


• Manufacturer: Aisin Seiki (Aisin)


• Application: Ram 2500/3500 heavy-duty models with the 6.7L Cummins


• Purpose: Built to manage high torque, towing, and heavy workload with durability and efficiency

Understanding these points helps explain why Ram chose the Aisin 6-speed automatic for the Cummins diesel and how it affects performance, maintenance intervals, and ownership expectations.

Was there ever a manual option?

In the current generation, there is no factory manual option for the Ram 2500 with the 6.7L Cummins. Earlier Ram heavy-duty configurations did offer manual transmissions with certain engines, but modern Ram 2500 diesels pair exclusively with an automatic transmission. If a manual is essential, it would require looking at much older or non-standard configurations and aftermarket alterations, which are not part of the factory specification for recent models.

Why the automatic pairing makes sense

The combination of the 6.7 Cummins and a six-speed automatic aligns with the truck’s mission: delivering substantial torque for towing, payload, and off-road capability while maintaining reliability over long service lives. The automatic setup streamlines shifting under heavy load, reduces driver fatigue on long hauls, and supports Ram’s emphasis on durability in the HD segment.

Maintenance considerations

Owners should follow the manufacturer’s recommended service intervals for the automatic transmission, including fluid and filter changes at specified mileages. Regular checks of transmission fluid level and color, along with attention to any unusual shifting or slipping symptoms, help preserve transmission life in a high-torque diesel application. If problems arise, professional diagnostic service is advised due to the critical role the transmission plays in overall performance and towing capability.

Summary

In current Ram 2500 models, the 6.7 Cummins diesel is paired with a six-speed automatic transmission built by Aisin. This arrangement prioritizes durability, towing performance, and ease of use in demanding work scenarios. A factory manual option is not offered in the present lineup, making the automatic the standard and expected configuration for this powertrain.

How do I tell if I have a 68RFE or Aisin?

You can tell the difference between a 68RFE and an Aisin transmission by checking the dipstick location in the engine bay: if it's on the driver's side, it's an Aisin, and if it's on the passenger's side, it's a 68RFE. Other ways include checking for an Aisin badge on the transmission under the truck or confirming your vehicle is a Ram 3500 with the high-output Cummins engine, which is exclusively paired with the Aisin.
 
This video shows the location of the transmission dipstick in a Ram 3500 with an Aisin transmission: 47sJayden.Gerber15YouTube · Mar 21, 2019
Method 1: Check the transmission dipstick location 

• Aisin: The yellow dipstick handle is on the driver's side of the engine bay.
• 68RFE: The dipstick handle is on the passenger's side of the engine bay. 

Method 2: Look for a badge on the transmission 

• If you can safely get under the truck, look for a badge that says "AISIN" on the transmission. This is usually located above the driveshaft on the driver's side. 

Method 3: Confirm your vehicle configuration 

• Aisin: This is the heavy-duty option typically found in Ram 3500s equipped with the high-output (>400is greater than 400>400 hp) Cummins engine. It is also standard on Ram 4500 and 5500 models.
• 68RFE: This is a common transmission in Ram 2500s and some 3500 models with the standard-output Cummins engine. 

Is the 68RFE transmission good or bad?

The 68RFE transmission is considered good for daily driving and light-to-moderate towing but is weak when modified or subjected to heavy-duty use. It is known for potential issues like overheating, torque converter shudder, and clutch failure, especially with heavy loads or engine power increases. However, with proper, frequent maintenance, upgrades like an aftermarket cooler, and careful driving habits, the transmission can be reliable for many miles. 
Good aspects

• Reliable for stock use: In a stock application, it performs well for daily driving and light towing. 
• Efficient power distribution: Its design handles high-torque demands and distributes power effectively, especially when towing. 
• Adaptive learning: The powertrain control module's ability to adapt to driving habits can contribute to long-term efficiency. 
• Upgrade potential: With appropriate upgrades, it can be made very robust. 

Bad aspects

• Weaknesses: It is prone to failure due to overheating, especially when towing heavy loads or in hot weather. 
• Clutch issues: Overdrive and 4C clutches are common points of failure, often exacerbated by heavy towing or high horsepower. 
• Valve body problems: Some factory issues, like low line pressure and problems with the switch valve, can lead to failures. 
• Shortened lifespan: Heavy towing, modifications, and poor maintenance significantly reduce its lifespan, which can be as low as 120,000–160,000 miles. 

This video explains the pros and cons of the 68RFE transmission in different applications: 59sFirepunk LLC YouTube · Aug 22, 2019
Recommendations

• For stock use: Keep up with frequent and regular maintenance to maximize its lifespan. 
• For heavy use: It is highly recommended to install upgrades like a transmission thermostat delete, a more robust aftermarket cooler, and stronger clutches. 
• For those who tow heavily: Be aware of the transmission's limitations and consider built options or an alternative transmission if your truck is frequently used for heavy hauling. 
• Avoid aggressive tuning: Significant horsepower increases can cause premature failure unless the transmission is upgraded to handle the extra power. 

What transmission is in the 6.7 Cummins?

The 6.7L Cummins engine is paired with either a six-speed 68RFE automatic transmission in older models (up to 2024) or an Aisin AS69RC automatic transmission in some heavy-duty applications. Beginning with the 2025 model year, it is paired with a new eight-speed automatic transmission from ZF.
 

• 68RFE: This is the most common automatic transmission in Ram 2500/3500 trucks with the 6.7L Cummins from approximately 2007.5 through 2024. 
• Aisin AS69RC: This is the heavy-duty automatic transmission option for some applications with the 6.7L Cummins, often found in higher-trim or heavy-duty models. 
• ZF 8-speed automatic: Starting in 2025, a new 8-speed automatic transmission from ZF is paired with the 6.7L Cummins engine. 

What year is the 68RFE transmission?

The 68RFE transmission has been used in Dodge and Ram trucks from mid-2007.5 through 2024, appearing in Ram 2500 and 3500 models equipped with the 6.7L Cummins engine. While its core design spanned these years, some components, such as the solenoid packs and valve body, have subtle differences between early (2007.5-2018) and later (2019-2024) models.
 
You can watch this video to learn more about the history and comparisons of 68RFE transmissions: 1mdieselrsmYouTube · Jan 3, 2020

• Production timeline: 2007.5 through 2024 
• Vehicle applications: Dodge/Ram 2500 and 3500 trucks 
• Engine: 6.7L Cummins 
• Key differences between early and late models:
  • Early models (2007.5–2018): Utilize a white solenoid pack. 
  • Late models (2019–2024): Use a blue solenoid pack. 
  • While the valve body is largely similar, the solenoid packs and check ball configurations changed during the production run.