Great points...........but check with the IH site, HP is down but the torque is at 620 on the 6.0!!


I remember a lot of debates here stating how much more the PSD could do with the SAME drivetrain as the motors with less torque.

People tend to forget about brakes, frames, linkages, axles etc....

Just 'cause the motor is making more power doesn't mean the rest of the truck can handle it (unless it's the 300 I-6........it can do ANYTHING!!!)

 

I agree on the 300 I-6. I had one in a '87 4X4. I just could not kill it. I tried. Wife told me I could get a new one if it went.

Well, it went, to her dad! He is still driving it. It has over 300,000 miles. The vehicle is shot, but whether it is 30 below or 110, it will start and go. I am just waiting for a phone call from him to come and get him, with the response

"Don't know what happened, I mashed the gas and the dang engine flew through the grille, leaving the rest of the truck behind!"

 

Argo- now there's something I didn't think about. The Kodiak's HP and Torque rating is quite a bit lower than what's on the 2500/3500 Silverado. Personally, I don't need 650 ft/lb torque in a pickup- 25 mpg would be nice though.

 

Ernie, did you check the IH specs???

The 6.0 has less HP but more torque than what's used in the F-series.......go figure.



When I win the lotto that Navistar made into a pickup will be my next vehicle......I want the 570(?) that makes 900+ pounds of torque....this will be my daily driver.

Don't be hating on me about being wasteful.........because the truck will also be used to tow my 40', triple big block, off-shore cat.

I know the Ford 300-I6 will do just fine but I want the extra cab space from the bigger truck.

 

Hating on you? Heck no! You could be my new best friend!!!

As to the lower Horsepower and higher Torque advertised by Navistar, that further leads me to believe that Ford (and of course, GM and Daimler/Chrysler) are revving these engines up higher than the original intent of the design in order to wring out more Horsepower. Also, keep in mind that these trucks are still using lighter duty transmissions and drive axles than their medium duty cousins, and the torque that they are really capable of might just spell disaster for these parts. Now I am not against a high RPM Diesel, Mercedes, BMW, and numerous other manufacturers have built some impressive, high revving diesel engines. However, these engines were designed from the ground up to be that way. The Diesel engines we are talking about here, however, were designed for low RPM grunt, and load pulling power. They weren't meant to be Horsepower factories, or to rev up higher to do it. Now maybe the engines have plenty of reserve capacity to handle it, maybe they don't, I don't know. I have admitted previously to being more partial to the Cummins and the old 7.3L Powerstroke. However, what I do know is that they don't seem to be having trouble with these newer diesels in the heavier chassis trucks. And if you think about it, they are pulling loads all the time in those trucks. So why the troubles in pickup truck land? I think it's because of a testosterone war between the big three. They keep winding them up higher, and pushing more horsepower out of them to out do one another. Instead of giving us what we need: a light truck diesel that'll make 4.6L V8 horsepower, 6.0L V10 torque, and 4 cylinder Ranger fuel economy in a half ton or light duty 3/4 ton truck that is more in line with the reality of what most truck buyers need, they give us what we want: a Muscle Car War. Except it's a Muscle Truck war, and it's Diesel Engines, not Big Blocks. Oh, and except for one more thing: it's really what they want, not what we want, the marketing department just does a helluva job convincing us that we really do need 650,000 Horsepower to tow a bass boat.

 

Well the marketing dept understands horse power, and so does the vast majority of the american public (or atleast they think they do, but most think that you can measure hp on a dyno too.) so they are making the hp numbers bigger, and bigger because thats were the people look to determine how good it is, instead of looking at the torque figures that really represent how much work the vehicle is going to be able to do.
BTW nice post.

 

When I win the Lotto, I'm buying your boat!

 

These trucks can make more power because they dont see near the same amount of work as a medium duty.

 

Yes, but they are tuned for less torque, which means higher RPM to get the horsepower. There are only two ways to increase horsepower. Higher torque, or higher revs. Horsepower is a function of torque and RPM. The formula is :

Horsepower = (torque x rpm)/5252. This means that if the engine maintained the same torque level as in heavy duty trim, it would have to spin faster to achieve greater horsepower. However, when you consider that in it's "light duty" trim it produces less torque, in must spin a great deal faster to make higher horsepower. This causes a great deal more stress on the internal engine components of a long stroke engine built for high torque, and low RPM. I think that this is where you'll find allot of the stresses that are adversely affecting these engines. Now, throw a tuner on there and boost the torque up sky high and extend the RPM range of the engine, and you have a real recipie for shorter engine life, IMHO.

 

The american public would not like a medium duty engine with a medium duty tune on it. They are very slow. Can pull a house but every day driveability would be lackluster. Thus the rpms. I have read about several of these high rpm engines pulling 1 million miles doing hotshot work. Im not sure the rpms are killing them. These engines are designed to go 350k miles without much trouble. It would take the average person 15-20 years to put enough miles on one to kill it.
Soot kills. These new engines with egr are going to suffer more from soot than from the higher rpms.
That said, I think if you want gas engine performance you should buy a gas engine. I want a diesel that drives like a diesel.

 

Absolutely right. Therefore, only people who know how to properly treat and run a diesel and respect it's capabilities would buy one. Besides, just a few years ago, 200-250 hp was considered rocketlike in a truck, hardly slow. Being operated by people who understand diesels and how to take care of them, and probably not winding them way up all that often. Absolutely right on this one. EGR is great for a gasoline engine, but not for a diesel. Right on. This is my point. For someone who wants a big fast truck who hauls something every once in a while they should get gas engines. The people who want a legitimate heavy duty work truck should get a diesel, but it should be available in medium duty trim. That is assuming the driveline in a pickup could handle medium duty torque.

 

Um.....how many Dodge or Chevy diesels are being used for ambulances?
Now subtract that number from how many PSD's are used. The trucks I see doing the most work, most of the time are Ford's. I respect the Cummins, but not the shell it sits in. Apparently the companies contracted to build emergency vehicles thinks similarly. <--- that is a wierd word.

 

Well chevy and dodge do not offer there diesel in there vans so there is huge part of the ambulance market that goes to ford. I think when chevy puts there duramax in there vans there will be some change. I really think that the reason that most emergency 1 ton vehicles are diesel is that there is already diesel fuel there at the fire station for the large fire engines. I don't see the cummins being in any emergency vehicles; it is engine that is really set up for towing " as a diesel should be". A PSD is a lightduty diesel that is set up to run more like a gas motor which does fit what emergency vehicles mainly do, Get in it, wind it up and drive like hell.

 

To the best of my knowledge (how good that is, I don't always know), the main reason for using diesel engines in ambulances is their low underbody and engine compartment temperatures. Ford has not made a gasoline ambulance chassis since the 80's. General Motors is making a gasoline ambulance chassis right now (I don't know if it is to capitalize on Fords unreliability issues with the 6.0), although Ford says that it isn't possible to use gasoline without causing safety issues stemming from the high underbody temperatures that would result. And I was never aware that GM doesn't put the diesel in their vans.

 

Good point about underbody temps. I don't know any chevy vans that they put a diesel in. I have heard people on forums saying that many fire departments are have problems with the 6.0. Maybe that is why all the fire and ambulances are 7.3 around here.