Dodge cummins 5.9 or 6.7 ?

The Class 4 & 5 trucks run a detuned CTD, yet are exclusively Aisin or manual - Engine output is not the whole story why the 68RFE is not offered. I think the 68RFE only has enough capacity for the SRW's but the main reason is it sold is because it offers higher profits than an outsourced transmission.

My prediction is that Allison will now need to step up its transmission once the DM is upgraded. I don't think it can handle the torque of the competition.

up2nogood wrote:

Bedlam wrote:
I think when GM started using the Allison around 2001 for its pickups, it made the others up their game. Ford brought out the 5R110 with the 6.0 PSD in 2003 and 6R140 with the 6.7 PSD in 2011 while Dodge held out until 2007 with the introduction of the 6.7 CTD and 68RFE (although still weak compared to the competition)and finally started using the Aisin in 2013.

Explain weak compared to the competition :h

Stock for stock, it doesn't have as much holding power as the other two transmissions. However, for our typical duty cycle for towing RV's and other typical trailers for a class 3 vehicle, it's adequate. The 68RFE (stock) is pretty much limited to 800 lbft of input as per RAM, which is why they don't offer a hotter tune stock for that transmission and why they went with the AS69RC Aisin transmission for the high output 3500's (which are pushing 900 lbft of torque at this moment). However, the 68RFE can be beefed up significantly to handle much more power as is the same case with other transmissions.

Did the op buy a truck yet?? 8 pages later.
Already said but I'd only get a 5.9 with a manual trans. The autos are ok but the gear splits on a 4 speed behind the Cummins are horrible.
The way used diesel truck prices are now I couldn't see buying a 5-10 year old one unless it was really a deal. It doesn't even take $10k extra to get an almost new '14 or '15 Tradesman CC Cummins over a late 3rd gen truck.
At the very least I'd drop the couple thousand more on an early 4th gen.

I thought the same Allison 1000 was used in the Kodiak C4500 and C5500. I know 2005 was the year it went from 5-speeds to six but little else changed. Class 6 was the Allison 2000.

Bedlam wrote:
The 6R140 is used all the way up to the Class 7 trucks. The Allison was used in the larger GM trucks when they had that line. The 68RFE is not available in Class 4 or larger trucks. There is a reason for the Aisin in the Ram line and its not just about PTO capability.

A friend has a Kodiak with the DMax and Allison. He said the trans in his MDT truck is a heavier duty unit than in the pickups.

Cummins12V98 wrote:

up2nogood wrote:

Bedlam wrote:
I think when GM started using the Allison around 2001 for its pickups, it made the others up their game. Ford brought out the 5R110 with the 6.0 PSD in 2003 and 6R140 with the 6.7 PSD in 2011 while Dodge held out until 2007 with the introduction of the 6.7 CTD and 68RFE (although still weak compared to the competition)and finally started using the Aisin in 2013.

Explain weak compared to the competition :h

I can personally attest to the 68RFE being a very capable trans. I sold my 2011 RAM Dually with 3:42 gears towing 28-29K combined and it never gave me an issue. Here is the pan at 65K just before I traded the truck. Fluid had about 50K.

I guess time will tell on the 68, no issues with mine so far.

Still waiting for an answer on what made the 48 such a great tranny. I was under the impression they were pretty troublesome .

The 6R140 is used all the way up to the Class 7 trucks. The Allison was used in the larger GM trucks when they had that line. The 68RFE is not available in Class 4 or larger trucks. There is a reason for the Aisin in the Ram line and its not just about PTO capability.

up2nogood wrote:

Bedlam wrote:
I think when GM started using the Allison around 2001 for its pickups, it made the others up their game. Ford brought out the 5R110 with the 6.0 PSD in 2003 and 6R140 with the 6.7 PSD in 2011 while Dodge held out until 2007 with the introduction of the 6.7 CTD and 68RFE (although still weak compared to the competition)and finally started using the Aisin in 2013.

Explain weak compared to the competition :h

I can personally attest to the 68RFE being a very capable trans. I sold my 2011 RAM Dually with 3:42 gears towing 28-29K combined and it never gave me an issue. Here is the pan at 65K just before I traded the truck. Fluid had about 50K.

transamz9 wrote:

Old-Biscuit wrote:

Me Again wrote:
You really do not want a 3rd gen with the 48RE auto, and you said you are tired of shifting! Chris

:H

Sorry Chris but have to disagree

2007 3500 5.9L CTD w/48re tranny towed 14K 5vr FT for 7 yrs. from border to border/coast to coast and have a US Gear EB since new.
Tow/haul mode majority of time and in OD

48re is a decent tranny....just needs to have routine maintenance every 25K (fluid change/band adjustments)

Truck is now 9 yrs old (bought it Nov '06), 140,00 miles and puts a big ole grin on my face every time I climb a 6-7% grade. Just sit back and listen to it hummmmmmmmmmm

I'm with you on this. I'm still on my OE 48 in my 2005 and have been running a programmer for years towing well over it's GCWR.

And that means there were not a lot of issues with the 48, or just yours. As said no issues with the crappy 4R100 that I had, but it still was a crappy transmission compared to its predecessors .

I find it a bit hilarious when a known problem with certain transmissions, motors or whatever, and one comes on here claiming how great they are . :R

Bedlam wrote:
I think when GM started using the Allison around 2001 for its pickups, it made the others up their game. Ford brought out the 5R110 with the 6.0 PSD in 2003 and 6R140 with the 6.7 PSD in 2011 while Dodge held out until 2007 with the introduction of the 6.7 CTD and 68RFE (although still weak compared to the competition)and finally started using the Aisin in 2013.

Explain weak compared to the competition :h