Ram HD 1000 lb-ft MPG loop
Towing 29k. Nice to see they have a gauge that tells you how "full" the DPF is now. That's handy.... VIDEO Almost 9mpg pulling 29k, which means about 37,000 GCW. Pretty incredible. Interesti...
Forum Discussion
ShinerBock wrote:
That is not accurate and this old assumption needs to go away with the Dodo. Whether it is a 500 hp marine ISB or a 200 hp ISB in a school bus, the stock ECM has the ability to de-fuel to protect itself if need be no matter what peak power it is rated at. It is not like fixed mechanical fuel delivery systems of old. There are two main reasons Cummins de-tunes these engine and neither have to do with protecting the engine since it can already do that at various power levels.
The first reason is emissions. There different emissions certifications for each GVWR. Since US emissions is measured in grams per horsepower per hour, emissions play a major role in how much horsepower an engine is allowed to make along with the GVWR of the truck it is going in.
The second reason is because Cummins and most medium/heavy duty truck makes sell different power levels at a premium. An engine may have 5 different power levels for a certain GVWR and application with the only difference being engine calibration. Cummins and these truck manufacturers are able to up charge additional horsepower similar to how the up-charge HO outputs in the pickups.
Case in point, the trucks mich800 probably drove was either a Freightliner M2 or International MV. Both offer a Cummins ISB with several power ratings between 200 hp up to 325 hp. How much power you want depends on how much you want to pay. Being that Ryder is a rental company, they probably don't care to pay for the higher power and actually want you to take as long as possible with the truck so they can charge more. Another company that uses the exact same truck set up in their own fleet may want to pay for the additional power since time is money.
Thank you for the input. It was a Freightliner chassis 26k gvwr but I was only hauling around 10k. Which is the payload limit for non cdl and the limit for the rental. It was frustrating trying to merge onto expressways and limited at 70mph means no run at any smaller hills so cresting a 50 was not uncommon. It was a very easy truck to drive but you better be planning your moves way ahead of time.
