Is The G56 6 Speed Really Bad?

[PGiannetto]

I have the G56 6 speed transmission. It was my only choice during Dodge's Big sale (employee pricing). I pull heavy loads about 3 or 4 times a week. Most loads are 17,000lbs (trailer only). So far the transmission feels great. What have been the issues if any? My '03 had the 48re auto. I heard alot bad things about it, but it is still running great. Any info would be great! Thanks!

 

[nps]

There are no known weaknesses - just speculation.



There is speculation that the dual mass flywheel won't hold up.



There is speculation that the G56 won't hold up because it has reduced torque input ratings compared to the NV5600.



And there is general unhappiness on some people's minds that the overdrive ratio makes the G56 with 3. 73 gears about the same final drive as the NV5600 with 4. 10s.



Drive it and be happy you got a good deal.

 

[LDobie]

17,000 lbs trailer only?? And with a 3/4 ton shorty?? Wow, they sure can tote the loads can't they?? Back when I was younger and dumber, I hauled a load of fertilizer and lime on an equipment trailer, 6 skids on the trailer at about 2K each and 1 in the truck. Truck was a '93 1 ton SRW cheby, scary to say the least, didn't dare go over 35mph. They've sure come a long way in 12 years!!

 

[67guzzler]

Other than the ratio issue that nps mentions and some driveline slack, I'm very happy with the G56. Overall I love the truck. I wouldn't worry about your G56 if you get past the first 500 miles. Service manager said that is where the 1 quart low lube failure will occur if yours is an early G56 and it's catastrophic. Enjoy.

 

[PGiannetto]

I was wondering why when i am in 6th gear 60-65 MPH seemed to be getting topprd out. Thanks nps you answered a question I had.

 

[Cummins Cowboy]

well here is my . 02, I don't think anyone knows how well the trans will hold up in our application but lets look at a few things that can give us clues, 1st, its a getrag trans, go to the first gen forum and ask them what they think of the getrag, its essentially a 4 letter word to a first genner. couldn't they call it something else?? 2nd, they are using a funky flywheel to dampen the cummins power pulses, why do they need to do that?? also the overdrive gear is wrong IMO which results in moveing the crusing RPM up, more RPM is easier on the transmission combine that with the flywheel indicates possibly DC is trying to baby a weak transmission that is at its limits with our application. However the worst thing IMO is the overdrive ratio which essentially forces everyone to have crusing RPM like the 4:10 people do

 

[67guzzler]

Cummins Cowboy --



You made a common mistake. It's not a Getrag. It's a Mercedes Benz G56 (the G is what confuses everyone) and it's made by Mercedes Benz in Brazil for their medium duty trucks.



Please see: http://www.mbnz.org/news/news.asp?id=106



-Jay

 

[Cummins Cowboy]

ok i stand corrected, wasn't the orginal getrag made by a german company?? seems like people here referred to it as a getrag

 

[67guzzler]

You're right -- others mistake it for the Getrag all the time. No biggie! I think the 1st gens really had the Getrag if I'm not mistaken.

 

[Tony T.]

Talking to my neighbor the other night, he commented he liked his 03 with the NV5600 better than his new 05 with the G56. He said he didn't care for the higher RPM on the G56. Just reporting his comment, I have not test drove either one myself.



Tony

 

[DPKetchum]

Well my 02 worth. VERY FEW problems reported on 48RE'S. Other then the intial launch of the G56 no problems reported on them. So the rest is purly speculation so far.

 

[JayB]

Before ordering my 05 I drove several 04s. When it arrived I felt the G56 shifted much smoother than my ford ZF six speed or the NV5600. I wish it had alittle more OD but I would think its perfect for towing 17,000lbs. Jeff

 

[PGiannetto]

yes it pulls the 17,000lbs with nno problem even up a steep grade. The problem was coming down the grade. The trailer really was pushing me. That is why I have a "Jake Brake" now.

In 6th gear the motor is winding at about 1950 rpm.

 

[bighornram]

There are no known weaknesses - just speculation.



There is speculation that the dual mass flywheel won't hold up.



There is speculation that the G56 won't hold up because it has reduced torque input ratings compared to the NV5600.



And there is general unhappiness on some people's minds that the overdrive ratio makes the G56 with 3. 73 gears about the same final drive as the NV5600 with 4. 10s.



Drive it and be happy you got a good deal.

I traded my 02' in for my "good deal". The 02' was a GREAT truck; can't think of one thing I didn't like about it. I am just finishing the breakin proceedure outlined in this forum, 1000 empty, easy miles then following the manual's suggestion not to exceed 50 mph for the first 500 miles pulling (that was difficult). The obvious difference it the ratio/RPM difference in 6th gear. I am only noticing an increase of 200 RPM in 6th gear @60-65 mph. Is this really that much to be concerned about? I am very happy with my new truck and am looking for it to be as good as, or better than my 02'.

 

[Cummins Cowboy]

well it depends on how important cruise RPM is to you 200rpm is huge in light of these trucks operating in a very narrow range of RPM. its like your engine adding 10mph cruising speed, which will translate in to much poorer fuel effeciency

 

[BigEasy]

200rpm is huge in light of these trucks operating in a very narrow range of RPM

Since when? I thought that's why we bought diesels... for a broad power range...

 

[Cummins Cowboy]

ok well most operate their trucks from 1700-2300, will it pull in other RPMS yes. but this is where the truck is most comfortable and effecient. the cummins does have a broad power range, because its right in the middle of the trucks normal operating speed. with that said isn't 200RPM a significant # considering the above RPM??

 

[EBottema]

Since my posts were remove, let me stay on topic this time. Yes, when you replace dual mass flywheel your wallet will feel pretty light and when your light duty trans wears out you will wish you had a heavy duty NV5600...

 

[DPKetchum]

Your posts were removed? Why? We'd be lost without your insight and knowledge.

 

[nps]

Like I said - just speculation...



Funny how the only nay sayers are 2nd gen owners (and one comment from the weight police). :{