G56 vs 68RFE

[EMoroney]

I am considering buying a new 2011 or 2012 3500 Dodge Cummins. I have always been a manual transmission guy and wouldn't have even considered the possibility of buying a automatic in these trucks before the 68RFE came along. From the news I have read so far, this seems to trully be a solid transmission that is able to handle the Cummins. I know the Cummins mated with the 68rfe is available in the high output package that raises to 800 lb/ft as opposed to the 610 lb/ft of the G56. Anybody else been in my shoes and has switched to the 68rfe? Concerns about both/either?



Thanks

 

[Grizzly]

I too have never had a truck with an auto and have had only two cars with auto, only because they didn't offer a manual.



I believe it is now time to go with an auto in a Dodge. The 68RFE and the Aisin on a CC are far better than any other auto Dodge has had. Besides the only standard Dodge has is the G56, which has the infamous DMF (Dual Mass Flywheel). Personally, I'd get a CC with the Aisin 6 speed auto.



g

 

[Cosmo]

If I knew then what I know now, I'd have gotten an 05ish 5. 9 3500 with a manual.

The 68rfe is decent at stock power levels, and even at elevated power levels if you don't thrash on it.

 

[seafish]

If you read the recent articles on the G56 in TDR mag, as wellas search here, you will find that quite a few people are having issues with either the DMF on the G56, or the actual transmission itself. While this may be partly due to increased powere levels due to mods and programming, that does not explain ALL of the issues the G56 trannys are having. I myself have the g56 in my 2005 2500 4x4 that has shown me NO problems at 75k (knock on wood). I love rowing the boat, BUT if I had a choice between the G56 and 68RFE, I would likely go with the 68RFE due to its robust design, excellent gear ratios and shifting, and it's towing abilities.

 

[Whiteranch04]

Go with the manual transmission, soon as clutch goes out swith it to a Valair dual disc towing setup, add the Genos transmission finned coolers as soon as you get the truck, change the oil in it before the factory recomends and overfill it, get the added capacity front and rear diff covers as well as soon as you get it, if you use it medium the clutch goes out at about 50k, the g56 needs a oil pump inside it and a filter and magnet but thats another story, I have 4 diesels all with standards, the automatics still are worse than the standards, rebuilds are repeats of the same problem infested automatic, if u ever update or delete the egr for hp the auto is a time bomb waiting to bite you immho

 

[Grizzly]

Go with the manual transmission, soon as clutch goes out swith it to a Valair dual disc towing setup, add the Genos transmission finned coolers as soon as you get the truck, change the oil in it before the factory recomends and overfill it, get the added capacity front and rear diff covers as well as soon as you get it, if you use it medium the clutch goes out at about 50k, the g56 needs a oil pump inside it and a filter and magnet but thats another story, I have 4 diesels all with standards, the automatics still are worse than the standards, rebuilds are repeats of the same problem infested automatic, if u ever update or delete the egr for hp the auto is a time bomb waiting to bite you immho

Do you also feel that way about the Aisin 6 speed on the CC?

 

[GaryCarter]

I test drove the auto before I bought mine. The auto will downshift at WOT when it wants to, even when in range select. So you can prevent upshifts, but not downshifts.



Not acceptable for me for towing in the mountains. I want to use 100% throttle if needed to crest a hill and pick the gears myself.



If Dodge had a completely manual gear select like the new Ford autos I would consider an auto, but not the way it is now.

 

[DHuffman]

I got rid of my '07 because I did not like the G56. The 68RFE is a great transmission, and I have not had any issues with mine.

I usually prefer a standard, but the G56 / Cummins combo just did not feel right to me. My '91 F-350 with the ZF 5spd and the 7. 3L IDI is a great combo, and I guess that is what I was judging the G56 against.

 

[RustyJC]

I moved from the NV5600 in our 2002 3500 to the current truck with the 68RFE. We tow a 16,000 lb GVWR 5th wheel and couldn't be more satisfied with the 68RFE.



Rusty

 

[KLauber]

This thread should be titled IMHO!

IMHO,
Ken

PS Anyone want to recommend tires?

 

[Grizzly]

This thread should be titled IMHO!



IMHO,

Ken



PS Anyone want to recommend tires?

This thread should be titled IMHO! Why!



PS Anyone want to recommend tires? This thread is not about tires.

 

[HBarlow]

As always, those who have manual transmissions are going to defend them but read all the threads with complaints about dual mass flywheel failures. Everyone who has a DMF/G56 either has already or will soon replace the entire flywheel and clutch assembly with an expensive aftermarket set up.

Now threads are beginning to report failures of G56 transmissions. They are simply not a strong transmission.

The modern six speed automatics, either MOPAR or Aisin, are much better choices now. They are durable and offer much better gearing.

 

[gtoli]

Instead of offering an opinion, I'll just say towing, off road, highway, in town, etc. I've had no problems with my 68RFE as of yet.

 

[KLauber]

This thread should be titled IMHO! Why!



PS Anyone want to recommend tires? This thread is not about tires.

Joking and gentle sarcasm Griz!



Ken

 

[Whiteranch04]

Do you also feel that way about the Aisin 6 speed on the CC?

I have no clue about it to tell the truth

 

[ENafziger]

As always, those who have manual transmissions are going to defend them but read all the threads with complaints about dual mass flywheel failures. Everyone who has a DMF/G56 either has already or will soon replace the entire flywheel and clutch assembly with an expensive aftermarket set up.

Now threads are beginning to report failures of G56 transmissions. They are simply not a strong transmission.

The modern six speed automatics, either MOPAR or Aisin, are much better choices now. They are durable and offer much better gearing. <!-- google_ad_section_end --> <!-- / message --><!-- sig -->

The G56 transmissions obviously have their shortcomings. I do wonder sometimes though how a 68RFE would've faired under what I've put my G56 through?

I'm showing my ignorance here, but how does a 68RFE act at 650 hp and 4,000 rpm sled pulling? Does it have problems with overheating when pulling 23,000+ at a continuous 400 hp for hours on end? Does it hold up to the abuse of 37" mud tires fighting for traction, slinging mud, and rocking back and forth repeatedly between Drive and Reverse?

Obviously the above mentioned scenarios don't reflect the typical user nor the constraints for which the transmission was designed. However, I do know that the G56 lasted over 100k in the above conditions... would have the 68RFE lasted just as well?

--Eric

 

[RustyJC]

The G56 transmissions obviously have their shortcomings. I do wonder sometimes though how a 68RFE would've faired under what I've put my G56 through?



I'm showing my ignorance here, but how does a 68RFE act at 650 hp and 4,000 rpm sled pulling? Does it have problems with overheating when pulling 23,000+ at a continuous 400 hp for hours on end? Does it hold up to the abuse of 37" mud tires fighting for traction, slinging mud, and rocking back and forth repeatedly between Drive and Reverse?



Obviously the above mentioned scenarios don't reflect the typical user nor the constraints for which the transmission was designed. However, I do know that the G56 lasted over 100k in the above conditions... would have the 68RFE lasted just as well?

Quite possibly not, but yours was not the application profile I took away from the original poster's question.



Rusty

 

[ENafziger]

Quite possibly not, but yours was not the application profile I took away from the original poster's question.

Rusty<!-- google_ad_section_end --> <!-- / message --><!-- sig -->

No doubt you're correct... I was mostly asking out of personal curiousity.

However, should the original poster decided to increase the power of his truck someday, to what extent is the 68RFE able to handle additional power over stock? Can this transmission be built to handle 450 hp? 500? etc?

I like rowing gears sometimes, but do admit it would be nice to drive around town without having to worry about shifting. If I was buying a new truck now, I would be in the same quandry as the OP.

Could it be said that a new automatic is just as reliable as a manual transmission for stock power levels? But that the manual transmission would take more abuse outside of those boundaries?

 

[HBarlow]

Eric,

I cannot personally answer your question about the ability of the new automatics to handle the power levels you mentioned. I don't know if anyone is building the internal hardware for them to do that.

If I had to guess, I would guess that with all the computer controls on engines and transmissions as well as emissions control and federal and some state enforcement attention to the emissions junk not many are interested in heavy modification any longer.

The new trucks are so much more refined and perform and drive so well off the dealer's lot why modify them?

 

[Cosmo]

I can't speak for the 4th gen trucks, but the transmission tuning in my 08 was absolute garbage. 6th gear with the torque converter locking up at ~45 mph? Yeah, right... that's what, 1100 rpm? Forget it.

When my trans was bone stock, it held up to ~500 horsepower and ~1100 lb-ft at the tires, until I decided to do a 4wd launch under boost. Then I melted my entire underdrive clutch pack.

With the stock trans, I pulled a 15k pound trailer across the country, and I yanked a 40k+ pound sled across the fairgrounds.

When I rebuilt the trans, I used Suncoast's valve body, pump pressure valve, clutches, torque converter, and flexplate. The pressure valve requires a modified TCM.

When my TCM got overwritten on accident, it took out my overdrive clutches due to poor shifting.

The shafts, gears, case, and all of the other hard parts held up just fine to ~1100 lb-ft of torque and a fairly heavy foot in some abusive situations.

It's a good trans. It's even better with H&S's Overdrive transmission tuning.