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High Output (AISIN) vs Standard (68rfe)

I'm happy with my regular tranny. I'm understanding that the Asian trannies are more durable, and can handle a bigger load. Whereas the American trannies are a smoother ride. I don't abuse my tranny so it should hold up ok.
 
Yeasty McFlaps said:
I'm happy with my regular tranny. I'm understanding that the Asian trannies are more durable, and can handle a bigger load. Whereas the American trannies are a smoother ride. I don't abuse my tranny so it should hold up ok.
Click to expand...
I should also add that the Asian trannies are generally sexier than american trannies. :D
 
My SO transmission was more than up to the task. I wasn’t looking when I bought but can’t wait to see how the HO with extra power does


Sent from my iPad using Tapatalk
 
Took my HO/Aisin on her maiden voyage today and this Aisin shifts similarly to the 68rfe in my 2016 2500 cummins truck.

To be honest, the driving experience between the two transmissions is very similar, just with a shlt ton more power out of the HO motor.



 
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gimmie11s said:
Took my HO/Aisin on her maiden voyage today and this Aisin shifts similarly to the 68rfe in my 2016 2500 cummins truck.

To be honest, the driving experience between the two transmissions is very similar, just with a shlt ton more power out of the HO motor.



Click to expand...
Awesome truck. I'm still glad I have the SO, due to the narrower hips...
 
thestuarts said:
Watch this video: Here's how the Cummins Diesel in the 2019 Ram HD Makes a Huge 1,000 Lb-Ft of Torque! Here is a summary of what's stated in the video:
  1. The HO block is made out of Compacted Graphite Iron (CGI) material which is stronger.
  2. The crankshaft is strengthened.
  3. Stronger main bearing caps with larger bolts.
  4. The flywheel has 10 bolts for increased strength. The previous version had 8 bolts.
  5. The flex plate is thicker and stronger.
  6. The damper at the front of the engine has been retuned.
  7. Increased the diameter of the piston pin and the bushings.
  8. The cam is now a hollow billet cam.
  9. They added a scissor gear to the front for Noise, Vibration and Harshness (NVH) control.
  10. Hydraulic lash adjusters. This means there is no longer a requirement for overhead adjustment.
  11. An "enhanced" turbo charger.
  12. Bosh CP4.2 fuel pump to increase injection pressure. [This pump is controversial]
  13. It is 60 lbs lighter
  14. The maintenance interval on the breather filter has gone up to 75,000 miles.
  15. The anticipated life of the engine is such that at 250,000 miles 10% of the engines will need a rebuild and at 350,000 miles 50% of the engines will need a rebuild.
  16. A more efficient cooling system to handle the higher heat
  17. Increased cylinder pressure

Watch this video: Rod Romain explains the differences in the HO. Here is a summary of what's stated in the video:
  1. They increased the strength of the connection rods by going to a higher strength alloy.
  2. They increased the strength of the crankshaft by going to a higher strength alloy.
  3. They switched to a Compacted Graphite Iron (CGI) block.
  4. New heads.
  5. The turbo was improved for airflow (primarily on the compressor side).
  6. The fuel pump is a new high pressure pump [Bosch CP4.2]
  7. The injector lines were improved.
  8. The engine water adapter and water outlet are both made out of aluminum instead of cast iron to save weight.
  9. They went to a hydraulic lash adjuster. It is quieter, and it doesn't require a rocker adjustment at 100,000 miles.
  10. Overall, the weight was reduced by 60 lbs.
  11. They beefed up the Aisin transmission. The shift schedule was improved [this is controversial].
  12. They beefed up the transfer case.
  13. The front and rear drive shaft joints are larger, and they went to more of a CV-style joint with a slip-in spline. It is "more robust."
  14. They reduced Noise, Vibration and Harshness (NVH) control with new dampers.
  15. The exhaust hangers were redesigned.
Cummins' web site states states these improvements:
  1. A Compacted Graphite Iron (CGI) material for the block allows us to increase the cylinder pressure capability while reducing the overall weight by almost 60 lbs
  2. A new cast-iron cylinder head containing high-temperature capable exhaust valves actuated by all-new hydraulic lash adjusters in the block eliminates the need for valvetrain adjustment service intervals
  3. The heart of the engine is a higher-strength alloy crankshaft with a 10-bolt crank flange driving newly-designed forged connecting rods and new bearings which transfer power from the low-friction ring-wrapped pistons
  4. A new larger Cummins Holset variable-geometry turbocharger optimized with heavy duty bearings, and a new compressor-side housing is a key ingredient in the new ratings, pumping 33 pounds per square inch (psi) of fresh air into the engine
  5. The new fuel-delivery system includes a new 29,000 psi (2,000 bar) fuel pump and fuel rail with Cummins Filtration “filter in filter” NanoNet® technology

As @brutal stated, the HO engine also comes with the 12" rear end (code AAM).
Click to expand...
Howdy. I have a 2021 Standard output 3500. It is extremely quiet. The manual doesn't say anything about having to adjust the valve lash at 150k. I have done extensive searching online and on this forum and I cannot find a definite answer to the following question:

Does the standard output have a CGI block? And hydraulic lash adjusters? Hollow billet cam? Anybody know for sure one way or the other?? Thanks in advance
 
Yeasty McFlaps said:
Howdy. I have a 2021 Standard output 3500. It is extremely quiet. The manual doesn't say anything about having to adjust the valve lash at 150k. I have done extensive searching online and on this forum and I cannot find a definite answer to the following question:

Does the standard output have a CGI block? And hydraulic lash adjusters? Hollow billet cam? Anybody know for sure one way or the other?? Thanks in advance
Click to expand...

19+ RAM Cummins diesel trucks are all CGI and use hydraulic lifters.
 
Yeasty McFlaps said:
Thanks HO. How about the strengthened flywheel? Main bearings and all that?
Click to expand...

The engines are identical except for what is believed to be a head design due to the difference in compression between the SO and HO. I don't recall if anyone has been able to verify part numbers for the heads. It's entirely possible it's just a thicker gasket. It's also possible it's different pistons. I don't recall that anyone has fully vetted out the differences.

ETA: Reported to have larger injectors different pistons.​

The HO gets more boost, so different programming in the ECM.

If you're basing any info off the TFL truck video Andre did, it's full of misinformation. many of the online reporting is incorrectly conflating the HO as being "different" and the new CGI block, leaving out the fact that both are CGI.

The engines are within 1lb of each other, that should tell you something.

www.cummins.com

Cummins 6.7L Turbo Diesel (2021) | Cummins Inc.

In 2019, we celebrated a 30-year partnership with RAM truck that started with the Cummins 5.9L Turbo Diesel in model year 1989. The 2021 6.7L Cummins Turbo Diesel brings to the table even more horsepower and torque while maintaining the diesel’s historic durability and efficiency.
www.cummins.com www.cummins.com

www.cummins.com

Cummins 6.7 Turbo Diesel Unveiled in New RAM Heavy Duty at NAIAS 2019 | Cummins Inc.

Cummins Inc. unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque.
www.cummins.com www.cummins.com

www.cummins.com

Next Generation Cummins 6.7 Liter Turbo Diesel is First to Deliver 1,000 Pound-Feet of Torque | Cummins Inc.

Cummins Inc. (NYSE: CMI) unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque. In addition to an increase in torque, the engine also has a higher horsepower output taking the 2500 and 3500 heavy-duty RAM pickup truck customers to the next...
www.cummins.com www.cummins.com

VIN:3C63R3RL6LG14xxxx3C6UR5FL5LG2983473C7WRLEL4LG220684
ESN:59326xxx (HO)59402531 (SO)59364831 (CC)
2020 RAM 35002020 RAM 25002020 RAM 4500 CHASSIS CAB
Engine codeETMETLETN
PART
tappet547511254751125475112
camshaft540408854040885404089
piston534293953363935336393
complete head534017153401715405018
bare head534016953401695405016
long block547608154760815476082
crank534293753429375342937
Turbski545636554563655456365
injector528926652892665289266
 
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Brutal_HO said:
The engines are identical except for what is believed to be a head design due to the difference in compression between the SO and HO. I don't recall if anyone has been able to verify part numbers for the heads. It's entirely possible it's just a thicker gasket. It's also possible it's different pistons. I don't recall that anyone has fully vetted out the differences.

The HO gets more boost, so different programming in the ECM.

If you're basing any info off the TFL truck video Andre did, it's full of misinformation. many of the online reporting is incorrectly conflating the HO as being "different" and the new CGI block, leaving out the fact that both are CGI.

The engines are within 1lb of each other, that should tell you something.

www.cummins.com

Cummins 6.7L Turbo Diesel (2021) | Cummins Inc.

In 2019, we celebrated a 30-year partnership with RAM truck that started with the Cummins 5.9L Turbo Diesel in model year 1989. The 2021 6.7L Cummins Turbo Diesel brings to the table even more horsepower and torque while maintaining the diesel’s historic durability and efficiency.
www.cummins.com www.cummins.com

www.cummins.com

Cummins 6.7 Turbo Diesel Unveiled in New RAM Heavy Duty at NAIAS 2019 | Cummins Inc.

Cummins Inc. unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque.
www.cummins.com www.cummins.com

www.cummins.com

Next Generation Cummins 6.7 Liter Turbo Diesel is First to Deliver 1,000 Pound-Feet of Torque | Cummins Inc.

Cummins Inc. (NYSE: CMI) unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque. In addition to an increase in torque, the engine also has a higher horsepower output taking the 2500 and 3500 heavy-duty RAM pickup truck customers to the next...
www.cummins.com www.cummins.com
Click to expand...
Thanks for the links and info! I think it's part of Cummins marketing to not state outright that the engines are essentially the same. They always make it sound like the HO is more robust. But it makes sense not to manufacture two greatly different engines and camshafts, flywheels etc.
 
Brutal_HO said:
The engines are identical except for what is believed to be a head design due to the difference in compression between the SO and HO. I don't recall if anyone has been able to verify part numbers for the heads. It's entirely possible it's just a thicker gasket. It's also possible it's different pistons. I don't recall that anyone has fully vetted out the differences.

The HO gets more boost, so different programming in the ECM.

If you're basing any info off the TFL truck video Andre did, it's full of misinformation. many of the online reporting is incorrectly conflating the HO as being "different" and the new CGI block, leaving out the fact that both are CGI.

The engines are within 1lb of each other, that should tell you something.

www.cummins.com

Cummins 6.7L Turbo Diesel (2021) | Cummins Inc.

In 2019, we celebrated a 30-year partnership with RAM truck that started with the Cummins 5.9L Turbo Diesel in model year 1989. The 2021 6.7L Cummins Turbo Diesel brings to the table even more horsepower and torque while maintaining the diesel’s historic durability and efficiency.
www.cummins.com www.cummins.com

www.cummins.com

Cummins 6.7 Turbo Diesel Unveiled in New RAM Heavy Duty at NAIAS 2019 | Cummins Inc.

Cummins Inc. unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque.
www.cummins.com www.cummins.com

www.cummins.com

Next Generation Cummins 6.7 Liter Turbo Diesel is First to Deliver 1,000 Pound-Feet of Torque | Cummins Inc.

Cummins Inc. (NYSE: CMI) unveiled its next generation 6.7L turbo diesel engine boasting a first-in-class 1,000 pound-feet of torque. In addition to an increase in torque, the engine also has a higher horsepower output taking the 2500 and 3500 heavy-duty RAM pickup truck customers to the next...
www.cummins.com www.cummins.com
Click to expand...
Bigger injectors too from what I heard.
 
MEGA HO 3500 said:
Bigger injectors too from what I heard.
Click to expand...

I believe you are correct and that's a data point I failed to include.

ETA: Now that I think about it, the CP4.2 failure kit the dealers order appears to be a single part number so the injectors should be the same by that logic.
 
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With a couple of ESN's and a free quickserve account someone could easily determine the hardware differences in the SO and HO. That's how I found out about the piston/injector/cam differences on 4th gen PU vs CC motors.

I am willing to bet it's piston based. Comparing the stock ECM files the duration tables are identical, which tells me so are the injectors. Main differences are in torque limits, timing, airflow, and pilot/post injection. All of those differences appear based on compression and power output too.
 
So I want to add some more standard vs HO info. I bought a 2021 3500 HO (white). My father liked it so much that he went out and bought a 2021 2500 (gray). The two are very similarly equipped.

PXL_20210902_214505707.jpg
You can definitely tell a difference between how the two drive. Casual driving mine is more laid back, it doesn't really care what you do. The 2500 feels more... urgent? I guess is the right word. With that being said, you can definitely feel the power difference between the two.

As far as the transmissions, mine goes through the first few gears way quicker than the 68rfe. Jumping between the two makes me feel like it takes forever for the 2500 to make it through 1,2,3. The Aisin definitely shifts with more authority and firmness. I much prefer the Aisin over the 68rfe.

The 2500 gets better fuel economy. Stock for stock, I was getting between 17-18 on the highway while he's getting 20mpg easy. Both sit at the exact same rpm cruising 80mph.
 
GPurcell01 said:
So I want to add some more standard vs HO info. I bought a 2021 3500 HO (white). My father liked it so much that he went out and bought a 2021 2500 (gray). The two are very similarly equipped.

View attachment 23047
You can definitely tell a difference between how the two drive. Casual driving mine is more laid back, it doesn't really care what you do. The 2500 feels more... urgent? I guess is the right word. With that being said, you can definitely feel the power difference between the two.

As far as the transmissions, mine goes through the first few gears way quicker than the 68rfe. Jumping between the two makes me feel like it takes forever for the 2500 to make it through 1,2,3. The Aisin definitely shifts with more authority and firmness. I much prefer the Aisin over the 68rfe.

The 2500 gets better fuel economy. Stock for stock, I was getting between 17-18 on the highway while he's getting 20mpg easy. Both sit at the exact same rpm cruising 80mph.
Click to expand...

Great comparo!

My 2021 HO also gets 3-4 mpg less than my 2016 SO did but has A LOT more balls… subjective, yes, but you can certainly feel it.
 
Also to note: the exhaust brakes.

In mine you can definitely feel it slow the truck down... it works really well and I love using it all the time.

The 2500 barely makes a difference with it on or off. You can hear it but that's about it.
 
GPurcell01 said:
Also to note: the exhaust brakes.

In mine you can definitely feel it slow the truck down... it works really well and I love using it all the time.

The 2500 barely makes a difference with it on or off. You can hear it but that's about it.
Click to expand...

Interesting, the exhaust brake works great in my 2500. And yes I have driven a 3500.
 
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