Ram Cummins Vs GM Duramax Ike Gauntlet

[ib516]

VIDEO

My summary:
- they both can tow 12.5k lbs anywhere, even in the toughest conditions, with ease.
- the Duramax exhaust brake works too good?
- the GM's hitch is heavily reinforced and you may need to rig up something for the safety chains to easily attach if you bumper tow.
- buy the one you like from a dealer you trust will look after you if there are ever any problems.

[2003silverado]

FishOnOne wrote:
I believe it's fair to say that they didn't have either truck setup in the optimum setting. Which says a lot about the engineers of these trucks. The optimum setting should be clear and concise for anyone who drives these trucks.

I think it has more to do with the people driving them in these tests. It didn't take me long to learn the optimum way to tow with my Chevy, but if I got in your Ford right off the bat I wouldn't know the very best combination of settings but after a little while behind the wheel I could figure it out, and vice-versa for you.

It would be interesting to do a test with people driving the respective truck that they are very familiar with.

[FishOnOne]

ktmrfs wrote:
why didn't they set cruise control going downhill on the duramax? If you do with the exhaust brake on in tow/haul it will just hold the speed you set. works fantastic for me.

And yes, the GM reciever is a tough one for safety chains. I had to get different hooks for mine to fit easily. they could have done a better job.

I believe it's fair to say that they didn't have either truck setup in the optimum setting. Which says a lot about the engineers of these trucks. The optimum setting should be clear and concise for anyone who drives these trucks.

[spoon059]

Either way, all three diesels are more than up to the task for light weights like this. Like others have said, the difference between the fastest diesel and the slowest gas is mere minutes... on a roadway that is unlikely to ever be encountered by 95% of tower's.

Bottom line, all the trucks are pretty darn good. Diesels tow slightly faster and at slightly better fuel economy, but the gassers can still tow a LOT of weight up high hills. Buy what YOU (more accurately... your WIFE) likes and what you can afford.

[FishOnOne]

Turtle n Peeps wrote:
^^^^^ this. I agree with everything that was posted above. That's why the Dmax burned less fuel. But it could have went the other way depending on load.

I disagree in the fact we don't know the actual HP/Torque numbers because the trucks were not running at WOT and full boost. The truck that can put enough power to the wheels with less throttle and boost to meet the target speed is the one that will make the best fuel economy.

[ktmrfs]

why didn't they set cruise control going downhill on the duramax? If you do with the exhaust brake on in tow/haul it will just hold the speed you set. works fantastic for me.

And yes, the GM reciever is a tough one for safety chains. I had to get different hooks for mine to fit easily. they could have done a better job.

[Turtle_n_Peeps]

^^^^^ this. I agree with everything that was posted above. That's why the Dmax burned less fuel. But it could have went the other way depending on load.

[ShinerBock]

The 3.42 axle in the Ram might cause it to use more fuel when towing than the 3.73 in the GM if it has to run at a lower gear at a higher rpm(which it seemed to do from the limited screen shots). Peak power doesn't really matter here since they are trying to stay at or below 60 mph and both trucks can easily do that. So it just boils down to rpms each needs to keep it at 60 mph and how much power it is making at that rpm.

As you can see in the video, the Ram was at 2,050 rpm at 60 mph which is 4th gear(1.00:1) doing the math. The Cummins torque curve is fairly flat and the 800 lb-ft at peak probably dropped off to about 775 lb-ft by this rpm. Using this, the Cummins is making just over 300 hp(not calculating for elevation loss) at full engine power and the gears are multiplying engine torque to 2,650 lb-ft to the wheels.

The GM was in 5th gear(.71:1) at around 1,600 rpm at 60 mph in the limited shots of the dash. This is the rpm that it reaches peak torque of 910 lb-ft. With that, we know that the Duramax is making almost 280 hp(not calculating for elevation loss) at full engine power and the gears are multiplying engine torque to 2,409 lb-ft to the wheels.

If the Duramax dropped to 4th, then it would have been making more horsepower and sending more torque to the wheels, but would have been revving at around 2,250 rpm. I am not too fond of pulling a load like that up a hill at 1,600 rpm and would rather be in the 1,800-2,200 rpm range to keep EGT's as low as possible.

[ib516]

I'd bet the Ram would get the best mpg. It should, it has 3.42 axle ratio, and is down 60 or so horsepower and 110+ lbs-ft of torque.

[ShinerBock]

Trackrig wrote:

I agree, towing 12,500# isn't much of a chalange.
The Ford F450 towing 30,000# up the Ike.

Bill

Yeah and it was a challenge for the Ram 3500 when it did the same as well.

[Trackrig]

ShinerBock wrote:
I agree. Towing a 12.5k lb bumper up the Ike may be challenging for a gasser 3/4 ton, but not for any of the diesel mills. They just make it a "non event" which is what you want out of a tow vehicle. Maybe bumping it up to around 16.5k lbs or better yet a 13-14k 5th wheel might make the test a little more interesting.

However, I understand that they can only work with what they got. The trailer they have may not be able to carry 16.5k and the 3/4 ton trucks that the manufacturers provide them may not have the hookup for a goosekneck or 5th wheel.

I agree, towing 12,500# isn't much of a chalange.
The Ford F450 towing 30,000# up the Ike.

Bill

[rjstractor]

I think their test is as consistent as they can make it. For those who actually watched the test you know that both trucks passed their performance benchmarks with flying colors (despite Ram having a power/torque disadvantage on paper). It came down to subjective scoring, with the Ram being the big winner. On the performance side, it was pretty obvious that 12.5K is too light a load to accurately reflect what these trucks can do.

[rhagfo]

What I would like to see is for them to do a 200 mile mileage loop, of average towing some flat some hills. All three towing the same TT, then repeat with a slightly larger 5er and see how the two sets of mileage compare.
The worst part of their test is there is no consistency!

[ShinerBock]

N-Trouble wrote:

4x4ord wrote:
I suppose if they conducted an acurate towing fuel economy test where they started with a clean dpf and ended with a clean dpf it might be interesting.

Winner winner chicken dinner... Yet every diesel fuel economy comparison fails to even touch on regen frequency and duration which have a bigger impact on economy than anything else.

I can guarantee you that the DPF's were getting hot enough to passively regen up that hill. Anytime you are at high load for periods like that will trigger a passive regen due to the DPF getting hot enough without the use of extra fuel.


It is mainly when you are not towing or with a light load that the DPF needs to inject extra fuel to actively regen in order to get hot enough to oxidize the PM in the DPF.

[N-Trouble]

4x4ord wrote:
I suppose if they conducted an acurate towing fuel economy test where they started with a clean dpf and ended with a clean dpf it might be interesting.

Winner winner chicken dinner... Yet every diesel fuel economy comparison fails to even touch on regen frequency and duration which have a bigger impact on economy than anything else.

[ShinerBock]

I agree. Towing a 12.5k lb bumper up the Ike may be challenging for a gasser 3/4 ton, but not for any of the diesel mills. They just make it a "non event" which is what you want out of a tow vehicle. Maybe bumping it up to around 16.5k lbs or better yet a 13-14k 5th wheel might make the test a little more interesting.

However, I understand that they can only work with what they got. The trailer they have may not be able to carry 16.5k and the 3/4 ton trucks that the manufacturers provide them may not have the hookup for a goosekneck or 5th wheel.