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Aisin AS69RC vs Chrysler 68RFE - 6 Speed Transmission Comparison

Ram 3500HD with Cummins turbodiesel and Aisin transmission

Aisin AS69RC

The Aisin Seiki AS69RC six speed automatic transmission was introduced for the 2013 model year when Ram rolled out the H.O. 6.7L Cummins Turbodiesel, which one can only suspect exhibits performance characteristics that exceed the limitations of the company's 68RFE transmission. Ram claims the strength of the AS69RC is 64% greater than that of the 68RFE. If we assume the 68RFE's maximum engine input torque to be somewhere in the ballpark of the standard Cummins 800 lb-ft peak output, the Aisin alternative would feature an input torque capacity in excess of 1,200 lb-ft. In reality, Chrysler's claims are likely aimed toward the transmissions maximum rated weight carrying capacity, although its input torque should still remain far greater than that of the 68RFE.

The Aisin's deep first gear ratio and overall gear spread is favorable to that of the 68RFE, although in terms of the step percentage between gears (percent change in gear ratio between upshifts) neither transmission holds a clear advantage. The step between 1st and 2nd is significantly steeper in the AS69RC, but smooths out across sequential gear shifts. Keeping in mind that the Aisin is only found behind the High Output Cummins, one could suggest that the extra available engine torque compensates for the 1-2 shifts ratio leap.

Aisin AS69RC Transmission Ratios & Quick Specs

Gear

1st

2nd

3rd

4th

5th

6th

Rev

Ratio

3.75 : 1

2.00 : 1

1.34 : 1

1.00 : 1

0.77 : 1

0.63 : 1

3.54 : 1

% Step

N/A

88%

49%

34%

30%

22%

N/A

Transmission:

AS69RC six speed automatic

Manufacturer:

Aisin Seiki Co., LTD

Applications:

2013 - present Ram 3500 w/ H.O. 6.7L Cummins

Total Ratio Spread:

3.75 - 0.63

Shift Control Type:

Fully electronic

Weight:

350 to 400 lbs

Strength:

64% greater overall strength than 68RFE

PTO:

45 horsepower PTO provisions

Service Intervals:

Recommended transmission fluid replacement at 30,000 mile intervals, recommended transmission filter replacement at 60,000 mile intervals

Aisin's AS69RC requires fluid changes at 30,000 mile intervals and fluid + filter replacement at 60,000 mile intervals. In theory, the Aisin will cost you twice as much in fluid than the 68RFE over the course of its life if you follow Chrysler's "severe" service schedule. The Aisin transmission is equipped with PTO provisions, whereas the 68RFE is not. Both the 68RFE and Aisin AS69RC feature a relatively tall 0.63 to 1 second overdrive (6th gear) ratio. The relatively high overdrive ratio yields low rpm cruising speeds, promoting fuel efficiency in low load conditions. The Aisin transmission is clearly overall favorable to the 68RFE, although it is only available in Ram 3500 pickups and only with the High Output Cummins variant.

Ram 2500 with Cummins turbodiesel and 68RFE transmission

Chrysler 68RFE

Where as popularity of the Cummins Turbodiesel has never been questioned, Chrysler's transmission selection had been lackluster until the company introduced the 68RFE. Considering that competitors General Motors and Ford Motor Company had been using sophisticated five and six speed automatic transmissions since the early 2000's, Chrysler was trailing in the drivetrain department with their 48RE. Upon retiring the 5.9L Cummins and introducing the 6.7L midway into the 2007 model year, Chrysler also launched the 68RFE.

The 68RFE is leaps and bounds greater than any automatic transmission previously selected for the mighty Cummins Turbodiesel. It's undisputedly far more reliable and features a favorable gear spread than any previous automatic transmission used in a Cummins equipped Ram pickup. While 1st gear in the 68RFE is taller than that of the Aisin AS69RC, the overall gear spread and step between gears is comparable enough not to warrant either unit the advantage in this category. Overall strength is where the 68RFE falls short, although for all intents and purposes the transmission is more than sufficient for its intended applications. The Aisin is simply a transmission from a different category altogether.

Chrysler 68RFE Transmission Ratios & Quick Specs

Gear

1st

2nd

3rd

4th

5th

6th

Rev

Ratio

3.23 : 1

1.84 : 1

1.41 : 1

1.00 : 1

0.82 : 1

0.63 : 1

4.44 : 1

% Step

N/A

76%

30%

41%

22%

30%

N/A

Transmission:

68RFE six speed automatic

Manufacturer:

Chrysler

Applications:

2007.5 - present Ram 2500/3500 w/ 6.7L Cummins (standard output versions only)

Total Ratio Spread:

3.23 - 0.63

Shift Control Type:

Fully electronic

Weight:

Approx. 263 lbs

Strength:

N/A - Chrysler strength designation "8" on scale of 1 to 9

PTO:

None

Service Intervals:

Recommended fluid and filter replacement at 120,000 miles under normal service conditions, 60,000 miles under severe service conditions

Chrysler recommends replacing the transmission fluid and filters at 120,000 miles under normal service conditions and at 60,000 mile intervals under "severe" service conditions. Since we'd assume that all Ram-Cummins owners tow or haul at least occasionally, the 68RFE's only advantage over the Aisin with regards to service is less frequent fluid changes. The weight of the 68RFE is significantly less than that of the Aisin transmission, but the Aisin's 64% greater strength is more than worth 150 lbs of curb weight. For prospective buyers in the 3/4 ton market, the Aisin transmission is not available in the Ram 2500 (at time of publishing) and is limited to Ram 3500 applications.