Ike Gauntlet 2017 3500s DRW 22,800# load

4x4ord wrote:

Huntindog wrote:

4x4ord wrote:

travelnutz wrote:
Me Again,

DUH! HP is merely a theoretical calculation moniker derived from how fast the TORQUE applied to the drive wheels rotates them thus creating measurable RPM. HP is NOT a direct measurable value! Zero torque = Zero RPM and thus Zero HP could even be calculated. Even 1000 lbs feet torque with zero RPM = zero HP. There is Zero RPM if there's insufficient TORQUE to rotate the wheels. HP is merely a theoretical value calculation, not a measured value!

A "horse" does not have a given pulling or rotational strength value as there are vast differences is sizes and pulling strengths of all the various horses. A given size horse's pulling strength can be actually measured but which horse?

The more FORCE (TORQUE) one applies to wheel shaft, the more RPM's it will turn! No where is the word HP used or even involved to make the wheel turn to any RPM's!

TORQUE and RPM are measurable but NOT HP as it's only a theoretical calculation!

Read the article that meagain posted a link to. Power is the rate of doing work. Neither Rpm nor torque are needed to calculate HP. The formula: HP= torque x rpm/5252 is derived from the definition of horsepower(1 horsepower is the power required to lift 550 lbs 1ft in 1 second). If the formula involving rpm and torque were to be stated accurately it would read HP = torque x rpm x pi/16500.

No matter. It is a well known fact that 4.10 gears will perform better in towing than 3.73s
So obviously, if the DA had 4.10s it would do better.
At one time, the Ram/Cummins was available with 3 different gear ratios, and 3 different tow ratings.
I will leave it up to the math gurus to debate as to why that is.

On this particular hill the Chevy might have been geared right. It started out at 55 mph and averaged about 46 mph so it likely spent a fair amount of time at around 40 mph. With 235/80r17 tires and the 3.73 gears the Duramax would be running 2854 rpm at 40 mph in second gear. If it had had a 4.10 final gear ratio at 40 mph the engine would be turning 2427 rpm in 3rd gear or 3137 in 2nd gear.....In either gear the truck would have slowed down.


Edit: The Ford should have been pretty comfortable at 40 mph with 4.10 final drives. It would have been running in 3rd gear at 2662 Which is pretty close to peak HP.

I doubt the Chevy got down to second gear as it would have to drop down to close to 2100 rpms in 3rd gear before it would shift to second. This would have caused an overall slower average speed and increased the time for the run.

Are you also taking the transmission gear ratios into consideration with your calculations? The Allison has the highest gear ratios of the three transmissions, and along with the 3.73's it is at a disadvantage to the other two with their considerably deeper gearing. A closer comparison would have been if the Ford had 3.55's and the Ram with 3.73's. With Fords and Rams deeper geared transmissions, the final drive ratios would have been much closer, and who knows, maybe the results would have been different.

It would be nice if they included in their testing which gears and rpm's the trucks used for the run, transmission temp, engine temp, and how much the suspension drops in the rear.

Rich