Old G56 swap to a new G56

[Southbound]

TDR Brethren-



To date I have seen a lot of information on the differences between the old G56 and the new G56. For those who dont know the G56 in the 2008 model trucks have different gear / ratio in them compared to the old G56 in 2007 and older trucks. I currently have 3. 73 ratio in my axle but with my G56 the total ratio in 6th gear is around 4. 10!!! Which means my trucks loves that #2 diesel when on the highway. It appears Dodge has "noticed" the issue thus they have made improvements. So I was wondering if anybody has researched the new G56 and if the new gears are interchangeable??? It appears the transmission housing is the same... which is good however I would be scared to ask what the cost of a new transmission would be. I am hoping to find a way to get my hands on the new gears to convert to the "new" G56. Let me hear from ya and thanks in advance for your feedback!!



Southbound

 

[Motorhead]

I was fortunate enough, through the advice from the TDR to find a new '07, 5. 9 with the "AE" late ratio G-56. This is the same trans that is usd with the 6. 7. It is my understanding that you can't just change 6th gear for the higher ratio.
I also read on our site that a new, late G-56 was about $2500.
That doesn't seem like much as a guy can put $4-$5k in an automatic
I like my higher 6th but it still could use a bit more in 6th. Have you explored an overdrive?

 

[Southbound]

Motorhead-



Thanks for your reply. I am actually aware of the fact that you cant just replace the 6th gear... ..... I would like to replace the entire transmission and / or the gear set. Each gear in the new G56 is has a different ratio than mine so I would like to take advantage of that for sure. I have done some research on the over-drive solution which looks interesting but more complicated than what I want to deal with. I am hoping that I can find a source to buy a new gear set and install it in my original transmission ... ... ... ..... if its possible. Again I appreciate your response.



Southbound

 

[betterthanstock]

Also look into 3. 42 gears, might cost less, and would give you a better 5th gear for downshifting on highway, than the new g56 would. They have also changed I believe 1st gear. Yours is lower so it work great with the 3. 42.

 

[CKelley1]

i tow with my g56 in a 06 and at 65 mph it is exactly in the sweet spot , for pulling or towing the old g56 and 3. 73 is the ultimate if you use the truck like a car i can see where it might have use

 

[RED]

I have a g56 AE, maybe we could swap.

 

[JBonpua]

I have a g56 AE, maybe we could swap.

If you have the taller AE and wants to swap with the older shorter geared G56 then let's get er done. PM me if you want to do it. As I don't tow, the AE would work for me.

 

[DSTEPHENSON]

What is the best way to know which

G56 is in the truck. I just got rid of my

08 2500 6. 7 68RFE. To many questionable things to go wrong with it.

Found a NEW 07 3500 SRW G56. It had been sitting on the dealers lot for 20 months. They said they didn't have a 3500 SRW but I found this one sitting among the other trucks. Is there any identification on the side of the trans that will identify which one it is?

 

[KBalzuweit]

My 07 was 13 months old when I got it NEW too. Mine is an early 07 so its got the old G56 and it sucks on the highway. I wish I knew about this then I would have looked at the build date.

 

[Motorhead]

What is the best way to know which
G56 is in the truck. I just got rid of my
08 2500 6. 7 68RFE. To many questionable things to go wrong with it.
Found a NEW 07 3500 SRW G56. It had been sitting on the dealers lot for 20 months. They said they didn't have a 3500 SRW but I found this one sitting among the other trucks. Is there any identification on the side of the trans that will identify which one it is?

Look at the bottom right and see the letters AE. If you see AD then it is an earlier G56. Also check the trucks production date. It needed to be built in late Nov. - Dec. '06. Mine was built Dec. 16th, '06. You would like it if it has the right trans.
#ad

 

[Big_Horn]

i tow with my g56 in a 06 and at 65 mph it is exactly in the sweet spot , for pulling or towing the old g56 and 3. 73 is the ultimate if you use the truck like a car i can see where it might have use

I second that!! I pulled a 10k trailer for 4000 miles this summer and 65-70 was just right. Milage was a little crummy, around 11mpg, I chalk it up to most of the driving was at altitude and hill climbing. Wish I had planned my trip now, would have saved about $400 with just the difference in fuel prices.

 

[DSTEPHENSON]

Thanks Motorhead.

I have the AE. Haven't towed with it yet. It sure shifts better than the NV5600 I had in my '03.

 

[AH64ID]

i tow with my g56 in a 06 and at 65 mph it is exactly in the sweet spot , for pulling or towing the old g56 and 3. 73 is the ultimate if you use the truck like a car i can see where it might have use

Yeah my dad has a AD G56 and he can pull many more hills in 6th than I can with my NV5600.

 

[Motorhead]

Thanks Motorhead.
I have the AE. Haven't towed with it yet. It sure shifts better than the NV5600 I had in my '03.

Nice score! I only learned about the trans difference HERE on this site. I was inquiring about what was the best third gen with the 6 spd and someone told me what to look for. I have 15K on mine and the trans shifts like a passenger car. I think that our trucks will fit into the same "want to have" category as the early '98, 12v, 215hp with the 5 spd.
I drove MANY 4 and 5 spds in my 30 year run at UPS and a crappy shifting trans sure made the whole day hard. Yet, another truck that had a better type in it made the day bearable. The best 4 spd we had was the old NP435 that was in the old Ford chassis package cars. They had the old 300ci gasser 6 cyl. You could drive that trans all day without getting tired. The 5 spd that we had in later Ford chassis, 12v Cummins powered was an Eaton. It was a great trans. We had Internationals with the V8 diesels and the trans fought you all day.

 

[Southbound]

Brethren-



Sorry for the delayed response as I have been up to my ears in gators. Anyway alot of good information in your responses. I was curious on what the "AE" stands for... ... and now I know. First I totally agree with those who believe the old G56 is set up for towing. It truly does put you in the "sweet spot" when climbing hills!! However when rolling on the open road it drinks that diesel for sure!! Funny because I get better gas mileage in town compared to highway driving. I have thought about switching my rear-end ratio to 3. 42 but curious on the difference in overall ratio compared to running with a AD - G56 and 3. 73s??? I am hoping someone edumacated can help me with that. Note: I got a quote on a used G56-AE for $2500..... which is a little rich for me. Who knows that might be a deal but would need to factor gas savings which would result in probably a long ROI. Guys as always you are a wealth of information. I really appreciate the responses.



Southbound

 

[WOT]

Brethren-



Sorry for the delayed response as I have been up to my ears in gators. Anyway alot of good information in your responses. I was curious on what the "AE" stands for... ... and now I know. First I totally agree with those who believe the old G56 is set up for towing. It truly does put you in the "sweet spot" when climbing hills!! However when rolling on the open road it drinks that diesel for sure!! Funny because I get better gas mileage in town compared to highway driving. I have thought about switching my rear-end ratio to 3. 42 but curious on the difference in overall ratio compared to running with a AD - G56 and 3. 73s??? I am hoping someone edumacated can help me with that. Note: I got a quote on a used G56-AE for $2500..... which is a little rich for me. Who knows that might be a deal but would need to factor gas savings which would result in probably a long ROI. Guys as always you are a wealth of information. I really appreciate the responses.



Southbound

If you can buy the new G56 and then sell your old one for somewhere close to that you won't be out much. I've been considering the 3. 42 but looks like it will be around $1300 so not sure yet. I'm keeping an eye out for responses on how the 3. 42 does on the newer trucks. Maybe someday I'll run across someone with a new truck looking for the 3. 73 and we can do a whole axle swap... not good odds on it though. .