What does cummins have in store for the competition

[CBari]

I don't usualy post on the speculation post, but I will today. I can't say with any certainty but we have to remember that all of the big three now have some pretty big hurdles coming that they have to meet. The eight speed might be there strictly to to keep shift points in an emmision sweet spot that allows for more power and better fuel efficience. Is it really needed for towing or daily driving no but I am sure there is a reason that we would not ever know off.

 

[rscurtis]

AFAIK, there are no more emission hurdles in the pipeline- they're at virtually zero now. The next reduction will be CO2, which equates to better fuel economy, not any additional engine hardware.

 

[mpaulson]

One big issue not mentioned here is how long the engine last, how many miles before sinking $$$ into it. To anyone who dares to keep a truck past warrenty, this is rather obvious.

 

[Gary - K7GLD]

Speculation can be fun - but then, reality steps in...



Yeah, we're kidding ourselves that the Ford and GM engines "must run near redline for max torque" - they have been getting their torque down at low RPM just as Cummins does - and have more snap off the line for the drag racers to boot!



(Relative) simplicity and lifespan have been Cummins strong points - but emissions laws and complex electronics DO take their toll on MPG, and reliability - which is undoubtedly also true of Ford and GM as well.



BUT, after all the speculation and glitter - PLUS price tags that are astronomical - I'll stick with the 420 or so HP, and nearly 1000 Tq of my "old style" '02 - the power, reliability and 23 MPG empty and 17 MPG towing our 5er still keeps us grinning as we see the fuel stops we DIDN'T need, fade in our rearview mirrors...



You younger and richer guys can spring for the new stuff - we'll just sit back and count our growing savings... :-laf:-laf

 

[AWeiman]

i to have no intentions of upgrading from a 5. 9 anytime soon. however i just hope the 6. 7 will turn out to be as good as the 5. 9 has been. if not we'll be just like the ford guys driving 6 oh's talking bout how the 7. 3 is the only good motor ford had.

 

[domehead]

I have 7500 on mine so far with no problem from towing heavy which means from 9000 up 26000 and yes I had to shift down to go the hills but it never missed a beat. The break is miles is half towing and the other half transporting me. I am over all very happy with the engine and the truck.



Yes there is few minorr issues with it but not a deal breaker.

 

[HBarlow]

Speculation can be fun - but then, reality steps in...

Yeah, we're kidding ourselves that the Ford and GM engines "must run near redline for max torque" - they have been getting their torque down at low RPM just as Cummins does - and have more snap off the line for the drag racers to boot!

(Relative) simplicity and lifespan have been Cummins strong points - but emissions laws and complex electronics DO take their toll on MPG, and reliability - which is undoubtedly also true of Ford and GM as well.

BUT, after all the speculation and glitter - PLUS price tags that are astronomical - I'll stick with the 420 or so HP, and nearly 1000 Tq of my "old style" '02 - the power, reliability and 23 MPG empty and 17 MPG towing our 5er still keeps us grinning as we see the fuel stops we DIDN'T need, fade in our rearview mirrors...

You younger and richer guys can spring for the new stuff - we'll just sit back and count our growing savings... :-laf:-laf

Gary,

Your comment about low speed torque developed by the V8 diesels is not inaccurate but is also not completely accurate.

The V8 diesels definitely do NOT have more snap off the line unless using lower differential gears, lower tranmission gears, and/or a loose torque converter. Have you ever driven a manual shift V8 diesel? I have. They don't produce squat at low rpm.

With the magic of computer controlled fueling and timing a V8 engine can produce a flat or relatively flat torque curve beginning at a relatively low rpm but a V8 engine, due to the fundamentals of bore, stroke, and basic design will NOT produce peak torque naturally at low rpm like an inline six.

I don't know where the Furd and GM V8 diesels produce peak power. I have never seen a torque curve for them like Cummins provides.

Gasoline V8 engines certainly will not and can not produce low rpm torque like a gasoline inline six.

 

[Gary - K7GLD]

Gasoline V8 engines certainly will not and can not produce low rpm torque like a gasoline inline six.

Assuming both are equally taking advantage of best bore/stroke combinations for torque development, that's largely true, gas or diesel. It's equally true that a typical inline 6 engine is not reliably capable of the higher RPM peak HP of a V8...



BUT, the higher typical upper RPM limit of the typical V8 engine allows use of a higher differential gearing that enhances off-the-line acceleration, while still delivering excellent cruising and top speed RPM. Here's a clue - WHY did the early Dodge/Cummins 1st generation trucks commonly use 3. 07 differential gearing?



Easy - because the then-limited 2500 RPM redline FORCED the tall gearing for reasonable freeway speeds - that even THEN were about 80 MPH tops!



Perhaps not always the best compromise in a purely work oriented usage, but for many, V8 power is often a welcome trade off in *all around* usage - as in the case of most truck owners.



It's undeniably true that drag race records are established and held by V8 engines - while the vast majority of hard working OTR rigs are inline sixes...



They each have their areas of excellence - and so far, trying to switch their strengths, has been pretty much an exercise in futility - as in the case of Ford trying to get unobtainable reliable power from their infamous 6. 0...

 

[dlmetzger]

I don't know where the Furd and GM V8 diesels produce peak power. I have never seen a torque curve for them like Cummins provides.



Gasoline V8 engines certainly will not and can not produce low rpm torque like a gasoline inline six.

The following link is for the Ford and GM torque/HP curves.



Diesel Power Curve Comparison! 2011 Power Stroke V-8 vs 2011 Duramax V-8 - PickupTrucks.com News



I found the Cummins 6. 7L torque/HP curve for comparison below.



Cummins Every Time - Ram - 6. 7L Turbo Diesel



As far as gasoline engines making torque low in the RPM curve, direct injection is making this possible. The world of engine design is not static and old assumptions may not be true anymore.



First Drive: 2010 Lincoln MKT EcoBoost and MKS EcoBoost — Autoblog Green

 

[HBarlow]

Assuming both are equally taking advantage of best bore/stroke combinations for torque development, that's largely true, gas or diesel. It's equally true that a typical inline 6 engine is not reliably capable of the higher RPM peak HP of a V8...

BUT, the higher typical upper RPM limit of the typical V8 engine allows use of a higher differential gearing that enhances off-the-line acceleration, while still delivering excellent cruising and top speed RPM. Here's a clue - WHY did the early Dodge/Cummins 1st generation trucks commonly use 3. 07 differential gearing?

Easy - because the then-limited 2500 RPM redline FORCED the tall gearing for reasonable freeway speeds - that even THEN were about 80 MPH tops!

Perhaps not always the best compromise in a purely work oriented usage, but for many, V8 power is often a welcome trade off in *all around* usage - as in the case of most truck owners.

It's undeniably true that drag race records are established and held by V8 engines - while the vast majority of hard working OTR rigs are inline sixes...

They each have their areas of excellence - and so far, trying to switch their strengths, has been pretty much an exercise in futility - as in the case of Ford trying to get unobtainable reliable power from their infamous 6. 0...

I agree with everything you wrote here, Gary.

The part about the early Cummins-powered Dodges is particularly accurate from my point of view. I was in the market for a new tow vehicle capable of pulling a 9,000 lb. Airstream in 1994. I visited the local Dodge dealer and drove a Ram 2500 Cummins automatic. It was, IMO, a total dog. If offered bog slow acceleration and the 2500 rpm engine red line limited top speed and range in each gear. There is no doubt it was the torquiest and longest lasting towing engine offered then but I didn't want to own one. I bought a Furd F-250 with 460 gas V8. At the time I said that if Dodge ever offered an engine with higher rpm capability coupled with a six speed manual I would reconsider. I was more or less dreaming.

In late 1998 Dodge-Cummins offered the 24 valve engine and in late 2000 Dodge offered the NV-5600 manual six speed. I drove one in early 2001 and was VERY impressed. The amazing clutch engagement torque at idle and stunning torque rise at 1600 rpm was truly exciting for me. I bought my first ever Dodge, first diesel, and first dually. Loved the combination. That Dodge could pull an Airstream at 98 mph. It might have reached 100 mph if I hadn't worried about going to jail if a Texas DPS trooper caught me.

I was hooked on Dodge-Cummins and remain so today. I honestly would not buy a Furd or Government Motors truck at 50% of invoice.

A young Mennonite guy over in Seminole, TX recently added an axle shaft, wheels, and tires on a "hinge", a hydraulic cylinder, and a towbar on my existing box blade to make a height adjustable road grader to pull behind my Kubota. I took him to lunch in a Mennonite restaurant in Seminole and we rode in his chipped '04 Furd Sick. Ohh. I understand why so many guys, particularly the younger set, like the V8 diesels. The kid pulled out of the restaruant parking lot, got straight, and stomped the go pedal. The Furd downshifted back to first gear, broke both rear tires loose and screeched them through second gear, and hauled butt. Yep, they can be made to accelerate very quick. But if he hooked a heavy trailer behind it the engine would crash within 30,000 miles. Drag racing is not my reason for owning a diesel dually.

 

[MA2LA]

Ya in stock form the 2 V8 oil burners feel quick and do ok towing where the dodge does feel a little slow at times but tows great. But add a smarty to the cummins and holy crap it will get p and go like no other truck i have driven and at times i have to baby the pedal to keep it from just roasting the rear tires.

 

[SMorneau]

Does advertised hp really mean anything if the engine is defueled to save the transmission, or keep the heat down on long pulls? Seems to the peak output in real life hard use conditions would be determined by the computer controls and the cooling capacities of various systems.

 

[domehead]

The 6. 7 can make more power on the fly with out any issues. The main reason the power in the trucks have been keep at lower rating is the drive train. More power equals bigger parts to hold it together.

 

[Gary - K7GLD]

Ya in stock form the 2 V8 oil burners feel quick and do ok towing where the dodge does feel a little slow at times but tows great. But add a smarty to the cummins and holy crap it will get p and go like no other truck i have driven and at times i have to baby the pedal to keep it from just roasting the rear tires.

BUT, don't lose sight of the fact that those SAME power add-ons are available for the V8's too - and give them the same power increases OURS do...

 

['strokeThis_'07]

BUT, don't lose sight of the fact that those SAME power add-ons are available for the V8's too - and give them the same power increases OURS do...

Very true. A Smarty-tuned Dodge wont hang with a Spartan-tuned Ford 6. 4. Of course the Smarty is $685, the Spartan ranges from $12-1700, or up to $2k with exhaust and intake.



And EFILive for the GM trucks runs $799. And the same holds true, the Dodge wont go up against a well tuned EFI Duramax

 

[domehead]

BUT, don't lose sight of the fact that those SAME power add-ons are available for the V8's too - and give them the same power increases OURS do...

dodge had the engine de-tuned from cummins. This are the same engine that are installed in the big motor homes and pushing 1000 lbs tq plus from the factory. The main difference is the drive train. check it out. those units either have a cummins or a cat installed

 

[AClayton]

dodge had the engine de-tuned from cummins. This are the same engine that are installed in the big motor homes and pushing 1000 lbs tq plus from the factory. The main difference is the drive train. check it out. those units either have a cummins or a cat installed

And the those same Cummins engines are bolted in front of the Allison 1000..... the same transmission behind the D-max - In the MH platform's. The Freightliner FRED chassis is a good example-Cummins/Allison combo. The bigger pusher's have the bigger Allison's but the 1000 series is good to a GCWR of 26K.



Alan

 

[dlmetzger]

dodge had the engine de-tuned from cummins. This are the same engine that are installed in the big motor homes and pushing 1000 lbs tq plus from the factory. The main difference is the drive train. check it out. those units either have a cummins or a cat installed

I think the engine you are referring to is the cummins 8. 3L diesel with a maximum torque of 1000 ft-lbs. See the link:



Cummins Every Time - Cummins Technology - 2010 On-Highway - EPA 2010 ISC8. 3



The cummins 6. 7L from is listed with a maximum torque of 750 ft-lbs. See the link:



Cummins Every Time - Cummins Technology - 2010 On-Highway - EPA 2010 ISB6. 7



I have seen both engines (6. 7L & 8. 3L) in listed for motor-home use.