I'm saying they don't rate them to their full capacity--in fact, I'd be willing to say that they do maybe 85% of its full capacity to allow some for overage--just the numbers protect them from lawsuits. It's not that they were behind. It's that they wanted to safely increase the ratings and the best way to do that, is to wait until a new model is released, and then apply the new, higher capacity technology to it.

Look at it this way--unless it a really light payload F-250, I've never seen a SD or pre-SD era F-250 squatting because of being overloaded unless there was an insanely huge load, such as a front balanced trailer which is incorrect loading anyway. However, the comparable GM's seem to almost always squat when loaded to capacity, or even near capacity.

Fine example here: last year we planted about 20 acres of wheat at the farm and needed to get 2 pallets of sodium nitrate (top dressing) and the trailer was tied up with the tractor so we couldn't use it. We took my F-250 and my father's C3500 dually to the Southern States and got 1 pallet put on each truck. Mine was hardly squatting, and the Chevy dually was on the over load springs close to its bumpstops.
Maybe if we raise any this year and we do that again, I'll take some pics to prove it.

 

Since Ford started using the 3 inch springs in the rear waaaaaaaaaaaaaay back in the day, I'm hard-pressed to find an F-250 or bigger that's squatted really bad when loaded. I see Dodges with the front wheels almost off the ground all the time, squatted from the weight in the rear. I don't see too many Chevies even attempting to work around here, but the ones I have seen, they're all squatted, too. Looks like they're breaking just because they have a load, and I've seen a Ford hook to a trailer that a squatted Dodge just dropped, and the Ford didn't look any different than it's stock height.

 

Thats weird. I heard the opposite was true. The fords tended to squat with less weight. Next time you get a chance. Can you take pictures to illustrate?

 

I have personally wittiness this to be true, in front of Home Depot…constantly…and yes I am a Ford fan however I will ALSO tell it like it is…Dodges sink with the same number of sheet-rock in each one…

 

You must be thinking of a 4500lb. GVW F-150.

 

I guess it must of been in reference to the presuperduties.

 

Again, the F-150's are the only ones I've ever seen to squat under full load.

 

A chevy 1500 or a F150 is not exactly a hauling vehicle.

As to the origional question. Both Ford And Dodge have excellent engines in their diesel trucks. Ford also has a good truck to go with its engine. Dodge transmissions, electronics etc. seem to be more problematic.

 

If it's a truck, then it's a hauler. I agree, some 150s may squat, but with a full load, remember they have IFS.

 

This is a misnomer. If anything it will tow less. It makes less force. Force is what gets the load moving and can help it maintain its speed.

Case in point. Medium dutys may only have 250hp and 800lb ft of torque. If they thought higher rpm hp was all fired important to tow more. Then they by all means would have higher rpm hp. This is not the case. Torque is where its at when you are wanting to tow more. The hp represents how fast you will tow. Less faster. 800lb ft will get a very heavy load moving more easily than 400 lb ft. Even if they have identical hp.

Another example. Chevy makes a 6.0 gas engine with about the same hp as the 6.6 diesel. Which will tow better? The one with more force. Which one is faster. The higher rpm engine of course.

Higher rpm hp. Means it will be faster in a race. But. If I had to choose between engine #1 and engine #2 and I got stuck with a 40k lb load with a truck that could handle the weight. Id take the one that made more force. Sooner.

 

I'd choose the truck that was rated to tow the most and that I trusted.

 

Well. I think it would be wiser to go with a weight rating that matches your load. Cause an f650 might be a little too much for me.

 

A lil` overkill never hurt!

 

I think you might be a bit confused. A PSD is rated to pull either 20,000 lbs in the small trucks or up to 30,000 lbs with the 4x2 automatic 550. A PSD will always be putting out less-than-rated torque at all speeds while towing these loads, unless you start heading up a hill. Therefore, the issue is not how many pounds, literally, one or the other can tow with. A pickup truck can tow a freight train if it wanted. What limits the "how much" on towing is suspension, brakes, tires, etc.

The key to towing is maintaining speed. This is how/why a PSD is better for towing than a Cummins. The PSD will hold a highway speed with it's GVWR, but a Cummins will lose it.

It's apples and oranges when you break out an example like a 250hp 800 ft-lb engine. Our national highway infrastructure is not built to have 18 wheelers barreling over the Rockies and Appalachia at 75 mph. Shaving 1 hour off a 500 mile run is not economically worth it. These bigger engines, dynamically, are lower RPM engines. All you need is 250 HP, and you want a strong twist-force down low.

But the PSD has 325 horsepower HIGHER in RPM rating than Duramax or Cummins. Therefore, from an engineering perspective, it IS the best performaning engine for towing operations, for light-duty trucks, who expect to maintain highway speeds under general conditions. The horsepower, by the way, has the "force" already factored in. 325 horsepower taken from 570 ft-lbs is a sign of efficiency compared to an engine which makes 325 horsepower also, but needs more force (600 ft-lbs) to do it.

An engine with 325 horsepower ... but which needs 1,000 ft-lbs to create that ... is NOT a more efficient engine, and WILL require MORE fuel. The amount of torque is related to the strength of the combustion, and the stronger combustion generally requires more fuel in the power-stroke.

You seem to be bent on Cummins for no "Logical" reason.

 

I fully comprehend the less than rated torque concept. In these discussions it is usually assumed that the truck will be in a position where max power is required.

The engine that makes 1000lb ft will do so at a lower rpm. Requiring less fuel. I have mentioned some experience in uprate shops. The cummins that made 1000lb ft at 2000 rpm also got 20mpg. Lower rpm equals better economy. Less pumping losses. From an engineering point of view.

More fuel yes. But less internal friction.

Now, The marine and I poured over rpms torque and gearing and discovered the cummins would hold 65mph better thant the PSD. So once again. This assumption was disproved. The PSD with the higher rpms will always win a race. Yes. It is very very fast. No doubt about it. But auto vs auto the cummins is geared better for highway towing. For maintaining its speed. Not racing. But holding a gear. It has the advantage.

The PSD is making 517lb ft at peak hp. More force does not equal more work. That much is true. But it does mean it can move a heavier load more easily. Thats one of the reasons why 100% of OTR trucks use diesel and 95% of medium duty trucks. Now HD light duty trucks are up to almost 50% saturation. MORE Force. Not hp. Is what you need to tow. 200hp and 600 lb ft. Is all you would ever need. Unless you feel the need to race your tow rig. Then more power to you. No pun.

HUhuHUh. He said bent.