Yes, but its kind of nice to be able to tow 10,000+ pounds at 75+ without breaking a sweat all day long.
As much as I love the truck I can not stand to tow with my IDI.

 

I think the fact that a thread like this exists is fustrating to some diesel owners. I think it upsets them that a gas engine exists capable of being successful or effective for towing for some owners. It seriously dampens the "if you're going to tow, gotta have a diesel" way of thinking.

 

Yeah, they are a pretty tolerant group alright. I guess it's hard for them to fathom that not everyone worships their choice of truck...

 

OMG... Going up a hill is going to slow you down. Do you really think going up a hill is going to make that much difference?

Whatever... look here (at what I already posted):
2010 HD 16 Percent Hill Climb Test - PickupTrucks.com Special Reports

The gas engine makes it up a 16% grade that is about 800 foot long (sorry it's not 6 miles, but lets keep it based in the real word anyway).

Gas engine at the top got to 29.53 mph in 30.75 seconds

The 6.7 got to 31.56 mph in 26.74 seconds. You may want to note that it started slowing down at the top.

So the diesel got up the hill quicker, big surprise. I was so surprised that a bigger engine with a turbo could beat a smaller NA engine...

Now that your ego is all big, I'll let you in on something else... The Chevy diesel beat the Ford diesel on both hill tests. Granted it wasn't by much, but they did say the GM was the only diesel to hit 3rd gear, while the Ford and Dodge were both stuck in second. Using the logic that's been around here that means the GM engine must be better because it can do it in a higher gear.

Getting back to the point though; if you look at those graphs they plotted for the 3/4 ton gas and diesel you'll notice something strange. All 3 diesel trucks started loosing acceleration towards the end of the hill. All 3 gas engine trucks were still accelerating. Why is that?

The authors of the article stated that none of the gas engines made it out of first gear, while the all the diesels were in 2nd and the GM made it to 3rd. Gee... maybe what Josh (Phillip) has been saying is true, if you can hold the lower gears for a long time, you can create more force.

I bet if that hill was longer, the gassers would have caught up, simply because all the diesels would have been chugging away in 3rd and 4th gear while the gassers where in 2nd. True, the gasser would have used far more fuel, probably caused more wear on the engine and drive train, but it wouldn't have lost by much. Is that ideal for towing, no. The diesel is far more suite for towing because speed is not everything for towing.

That said, I've taken a 12k trailer up a 5 mile 5% grade and not lost speed. I maintained 75 mph all the way up. I averaged 6 mpg on the trip and my V10 was bouncing between 3rd and 4th at 3000 and 4500 RPM's, but it did it.

 

Here is something else from that site I find interesting. They actually compared the 6.4 PSd to the V10.

PickupTruck.Com - Part 2: 2007 PickupTruck.com Heavy Duty Shootout

Notice how empty, they are almost the same. Loaded the PSD starts to take a lead.

Also notice how on some of the other truck (i.e. GM and Dodge) the gas engines actually did the 1/4 mile faster than the diesels empty. Also note they lost far more speed when loaded down the the V10 did.

 

JR, we have talked about the 07 test over and over, that was srw v10 f250 against drw psd f350. And if you don't think the difference is much, look at the 2010 test.

And as far as whether the 6.2 or v10 would have caught up, we don't know. We have no clue what would happen when it shifts up.

And keep in mind, that test was 4.30 gears on v10 and 3.55 gears on psd. Put the psd in 4.10 gears and see what would happen. As it is, the psd outpulled the 6.2 hands down.

 

Yes, but I was more interested in was the other manufactures, and I didn't look into the truck specs they used on the other manufactures, but it is a valid point. (I thought the PSD had 3.73 though, ehh.. whatever) The Chevy on the other hand had 3.73's on both trucks, and at the end the gasser was faster unloaded, barely...

Anyway, yes the 6.7 out pulled the 6.2, but my point is that it is not like the 6.7 ran away from the 6.2, even though it had almost twice the torque. I would hope the 6.7 would out pull the 6.2, you have to be paying all that money for something?

From what I've seen, all that torque that the diesels makes only helps as the load becomes heavier. The torque means the truck has more force to keep the truck moving with a bigger load up a hill or accelerating on the flat. The gas engines can do it to, maybe slower, but the diesel will not run away from them unless you are getting to silly high altitudes or towing 20k lbs.

This is a concept I tried to explain 100 pages ago, but was told only hp matters. But nobody cares that hp is worthless if you don't have the torque to actually turn the axle. There is a synergistic effect between the two, you have to have both to move forward.

But having the 6.7 with 400/800 on empty truck, you won't be much faster than a 6.2 with 400/400. It's not until you really start loading the truck that you can make use of that 800 ftlb torque.

 

I want a strong truck too. I don't race my truck either. 260 hp is 260 hp and is going to pull the same amount of weight up a hill whether it is at 3,000 rpm or 4,500 rpm. Anything a 7.3 can pull at 3,000 rpm my 5.4 can pull at 4,500. Just because one turns more rpms to do the same job doesn't mean it is weaker or that is built for speed and not pulling.

 

Hp is all that matters. If you have more low end torque you also have more low end hp. That is why the gasser slows down more in these shootout tests from a dead stop. They struggle more to get the load moving because they have much less hp at low rpms. For example, the 6.4 has 650 tq at 2,000 rpm and the v10 has 410 tq at 2,000 rpm. That means the 6.4 has 247 hp and the v10 only has 156 hp at that rpm. If they both hit a hill doing 55 mph then all that low end torque(hp) just means it will climb the hill at a lower rpm, not that it will maintain speed better or can pull more weight.

 

Hey Krewat, I thought "everyone" was supposed to "cool it" with the "mild" insults...or is that just for me? For some reason, (which I don't know your reasoning, and you said I didn't) it's ok for Sand Man and others to fly in here and talk smack, (look up a few posts) but when I give it back, you jump in, censure me about it, and suggest I take a couple of days off before posting.

 

Sure it make sense. The induction system doesn't matter. I didn't 'add' a turbo to any of the engines, it's the way they came from the factory.

If I started adding parts, and counted them in the number, that wouldn't make sense.

We're talking horsepower and torq. Not what induction system has an advantage.

A lot of posters in this thread seem to think you can make these engines equal on paper and in reality. Can't be done. They are what they are.

You can look at the numbers however you want.

I think that they should make the truck weigh the same in the unload drag races. They would have to add 500lbs to the gassers to get them to the same weight. I think that would be a more fair race, if you really want to compare engine power.

 

It was 3.73 vs 4.30.

The 3.73 was the highest the 6.4 came with in that truck.
The 4.30 was the highest that came in the V10 truck.

They got the highest gears in either one. Thats the way Ford built them.
If the 6.4 gets after market 4.10s then the V10 gets to mod too.

 

Amen brother. You're explaining it perfectly. The torque matters more as you add weight. You'll never exert 800 ft/lbs with an empty truck. It moves too easily. Add 15k on a trialer and a dead stop on a 15 degree hill. let's see who can move the load better........torque or horsepower.

 

Yes, 260 hp at the tires is the same. The difference is that since the energy is being delivered as rotation motion through the gears and tires, some of the torque can be transferred to hp through the gearing in the truck.

This is why a diesel can be faster than a gas engine with the same or even a little more hp. The way the tranny and rear ends are set, allow it to convert some of the torque it produces to hp.

It all comes back to the hp=tq*RPM/5252 and how the gears interact to change the rotational speeds. Certainly 1 ftlb is not going to be converted into 1 hp, nor is the relationship even linear, but torque can be converted to hp and hp to torque.

What it takes to power a vehicle (rather it be a sports car or tractor trailer on flat or uphill) is far more complicated than just creating hp. You have to have a balance of torque too. Other wise we would all have Rotary engines screaming at 12,000 RPM's.

I understand your argument about gassers being able to hold a gear for long and such, and this why a diesel won't run away from gasser. But as you start loading the truck down with weight, more torque is required to keep everything moving up the hill or even accelerate on flat. Think you have to physically twist the axle more. No mater how much hp you have, if you are lacking the torque to actually make the axle twist, you aren't going to go faster. You will be limited by the weakest link, and for loaded truck and trailer, the amount of torque you will need to twist the axle is going to be huge, and gassers are just lacking that twist ability.

that is about as well as I can explain it without getting the books out and writing down equations. In which case the equation will be useless until all the gears and are plugged in anyway, which is way more work than what I'm going to go through for a thread.

 

Forced induction is adding displacement.

BTW your hp/tq per liter argument is flawed.

The 3.5l EB makes 104hp and 100tq per liter of displacement. If the 3.7l EB (F150) makes its estimated hp/tq it will put out 108hp and 108tq per liter.