6.7 Cummins vs 6.6 Duramax

[SoonerWing03]

As someone who knows next to nothing about Diesel engines, I am trying to figure out the strengths and weaknesses of these to. Any opinions would be appreciated.

[memtb]

SweetLou wrote:
Has any one considered recalls on ea brand or the maintenance costs for EGR or other servicing? It would play into my decisions, but at the end of the day, a lot goes into buying a new truck not just what they can out pull or if they get off the line quicker. That one still amazes me why they think racing an almost 8000 lb truck is even relevant.

If it floats, flies, or rolls....it was meant to be raced!

[Groover]

SweetLou wrote:
Has any one considered recalls on ea brand or the maintenance costs for EGR or other servicing? It would play into my decisions, but at the end of the day, a lot goes into buying a new truck not just what they can out pull or if they get off the line quicker. That one still amazes me why they think racing an almost 8000 lb truck is even relevant.

They are not really racing 8,000lb trucks. You hook 32,000lbs on the back and then race 40,000lb rigs!

[SweetLou]

Has any one considered recalls on ea brand or the maintenance costs for EGR or other servicing? It would play into my decisions, but at the end of the day, a lot goes into buying a new truck not just what they can out pull or if they get off the line quicker. That one still amazes me why they think racing an almost 8000 lb truck is even relevant.

[mt1729]

I have owned both. Both served me well. Power wise if buying new it doesn't matter anymore. You could hook either to a 30ft trailer and floor the go peddle and turn it into a 34 footer. If I was buying new I'd go with the ram cummins. They have improved the pickup itself a lot in the last few years. My chevy duramax 2002 was much quieter, the ride was better, it drove better and over all had a much nicer cab then what I have now, a 2006 Ram cummins. With that said I like the cummins enough better that I would buy it again. However if anyone is giving away any one of the big 3 with the diesel engine I'll be happy to take it. I'm pretty sure any new one will probably outlast me 🙂

[ktmrfs]

Cummins12V98 wrote:
Here is another thing to consider. What does CUMMINS do??? They build engines!

They sell the 6.7 to RAM but they also sell the same engine to others for Medium Duty applications. "True medium duty"

GM's D Max is used by what other Medium Duty Manufacturers? "Crickets"

Same goes for the Medium Duty AISIN transmission as it's used in many other MD applications.

"ALLISON" (GM Built), who else uses that trans for MD applications? "Crickets"

Well let's add another thing to chew on. Simply look around out on the Highways. What brand DOMINATES the "Independently Owned" RV and HotShot hauling market. RAM, there is simply no comparison.

Oh, they use them a lot to haul Fords. 😉

how many people buy a 3/4 or 1 ton truck for PERSONAL use and put 200K + miles of towing heavy loads on it let alone, 500K or so? Yes there are some, but most won't see enough miles or load to make a reliability difference on what the engine and transmission was designed for.

All three engines, transmissions and bodies are plenty fine and reliable.

I know owners of Dodge,Ford and GM that have put 250K + miles and had no reliability issues, just normal service by the book.

Drive them all and pick which one YOU (and DW) like the best.

I happen to prefer the Duramax, but a good camping buddy has a Dodge and when I ride in it, it is also a fine rig and has some things I like better than the duramax and things he likes in mine better than the Dodge. Likewise for the neighbor that has a new Ford with the scorpion engine.

Or son get a new work truck every 100K miles or so, has had a dodge, and ford a GM and his personal truck is my old 2004.5 Duramax. He has likes and dislikes about all 3. Depends on what one wants.

[Grit_dog]

Groover wrote:

Grit dog wrote:

SidecarFlip wrote:
I like them all so long as they smoke....

I'll drink to that! Roll coal brotha!

I sincerely hope that you too are joking. I was raised that when something I do offends others I needed to reconsider my ways, especially if that is the only reason for doing it.

Well if you think I’m (anyone ) is doing it just to offend you, you’re placing far too much self importance on the situation.
I was serious btw. I don’t go around intentionally blacking out intersections and rollin coal on people standing at the crosswalk, but your opinion of it is of little, make that no concern to me.

[FishOnOne]

Turtle n Peeps wrote:

RCMAN46 wrote:
"They also operate at lower engine rpms, which lowers the piston speed. Pretty much an irrelevant negative on the I-6!"

If you are comparing the Cummins with the Duramax then you are dead wrong.


Here are the facts.

The Cummins makes its peak torque at 1800 rpm
The Duramax makes its peak torque at 1600 rpm

The Cummins makes its max horsepower at 2800 rpm.
The Duramax makes its max horsepower at 2800 rpm.

So much for the popular belief that the I6 Cummins operates at a lower rpm than the v8 Duramax.

So the statement that the Cummins operates at a higher piston speed holds true when comparing to the Duramax.

So refreshing that someone gets it! 🙂

Give that man a cigar... :C

[Turtle_n_Peeps]

RCMAN46 wrote:
"They also operate at lower engine rpms, which lowers the piston speed. Pretty much an irrelevant negative on the I-6!"

If you are comparing the Cummins with the Duramax then you are dead wrong.


Here are the facts.

The Cummins makes its peak torque at 1800 rpm
The Duramax makes its peak torque at 1600 rpm

The Cummins makes its max horsepower at 2800 rpm.
The Duramax makes its max horsepower at 2800 rpm.

So much for the popular belief that the I6 Cummins operates at a lower rpm than the v8 Duramax.

So the statement that the Cummins operates at a higher piston speed holds true when comparing to the Duramax.

So refreshing that someone gets it! 🙂

[Cummins12V98]

Compare the redlines. I tow at 1,750 rpm at 60 in 6th and when climbing a grade maxing out a gear I am at 2,800-3,000. My redline starts around 3k.

[RCMAN46]

"They also operate at lower engine rpms, which lowers the piston speed. Pretty much an irrelevant negative on the I-6!"

If you are comparing the Cummins with the Duramax then you are dead wrong.


Here are the facts.

The Cummins makes its peak torque at 1800 rpm
The Duramax makes its peak torque at 1600 rpm

The Cummins makes its max horsepower at 2800 rpm.
The Duramax makes its max horsepower at 2800 rpm.

So much for the popular belief that the I6 Cummins operates at a lower rpm than the v8 Duramax.

So the statement that the Cummins operates at a higher piston speed holds true when comparing to the Duramax.

[blt2ski]

Buy the one wife likes the seats of. Otherwise, you won't hear last of it!
Reality, all have positives, and negatives.
A V vs inline vs pancake vs whatever design motor. Pluses and minuses of both! Piston rods on an equal displacement motors comparing an inline 5 to a V8 will be bigger no matter gas or diesel. As will other parts. Now we can get into how crank is designed for balance, firing of pistols yadda yadda! If rig meets your needs, kewl! If not, get a different one!
Marty

[SoonerWing03]

mtofell1 wrote:
I do keep an eye on the diesel trucks and well may end up with one again someday. I lean Ram mainly because that's what I've been driving and am generally happy with it. Also, for whatever reason, I think you get a lot more truck for the same money with Ram. Chevy/GMC would be next. Ford must be packing diamonds in the fender wells for what their trucks cost.

All 3 brands are great so you really can't go wrong. Research is key so you are doing it right, OP.

What’s up with Ford’s pricing??? They seem to be 5 - 10 K more for a comparably equipped vehicle. The RAM’s seem to be pretty close in price to the GMC/Chevys... maybe a tad bit cheaper.

[S_Davis]

No experience with the 6.7 but I have a 2009 lmm and a 2013 lml no serious problems with either. The 09 had the DPF fall off at about five years and was drag raced for two years(truck will do a 12.95@103mph in the quarter@7600lbs)with one glow plug replaced to date. No problems with the 2013 except for a bad def tank heater replaced under warranty.

[mtofell1]

My old 06 Dmax was a great truck but that was pre-emission and it seems everything is different now (I'm in a gasser btw). One thing I saw mentioned that I'll echo is that Dmax just ate front end parts - hubs, pitman arm, bushings, etc, etc. It seems like every time I took it in for an oil change it cost me $1700.

I do keep an eye on the diesel trucks and well may end up with one again someday. I lean Ram mainly because that's what I've been driving and am generally happy with it. Also, for whatever reason, I think you get a lot more truck for the same money with Ram. Chevy/GMC would be next. Ford must be packing diamonds in the fender wells for what their trucks cost.

All 3 brands are great so you really can't go wrong. Research is key so you are doing it right, OP.

[memtb]

Groover wrote:

Grit dog wrote:

SidecarFlip wrote:
I like them all so long as they smoke....

I'll drink to that! Roll coal brotha!

I sincerely hope that you too are joking. I was raised that when something I do offends others I needed to reconsider my ways, especially if that is the only reason for doing it.

I obviously missed what was offensive! Maybe I’m dense, or just have “dense” skin!