Ford Powerstroke VS Duramax and Cummings

[CRH]

The Ford 300 was probably the best engine they ever made. If you ever got a UPS package, it was likely delivered in a 300 powered truck.

I have had several inline 6 engines, Ford 300, Ford 200, a couple of Jeep 258s, and a Mercedes 3.0. I had no internal engine problems with any of them.

[switz]

Back in the 80s, I had a 560SEL Mercedes with the big V8 and the E class four wheel drive station wagon with the straight six. The six was smoother and quieter.

Have the 3.0L V6 in the 2007 Mercedes ML320 CDI (called a 320 because of the chip versus the 280 with a smaller tune chip in the rest of the world where there were two engine choices based upon the chip) and a 2002 E320 3.2L straight six diesel station wagon in the UK. Straight 6 once again is smoother and being all mechanical versus electronics driven, will last forever and gets great milage which is important when fuel prices work out to over $6 per gallon.

I had a Duramax V8 in a GMC 2500 a few years back. It just does not compare well in my memory with the straight 6 Cummins in my 2012 Ram 2500HD for both power and smoothness.

[crispyboy]

Don't forget the "Leaning tower of Power" - slant 6 engine in the Chrysler, Dodge and Plymouth vehicles. My mother once had these in two different Dodge Darts.

Currently have a 74' CJ-5 with the 258 straight six. Gobs of torque, hp not so much.

[HiHoAgRV]

Originally Posted by Countryboy59

I learned in engineering school that an inline six is inherently balanced. I'm convinced this is why the Cummins and the 4L Jeep sixes are such good engines.

Yup. One of the few details I still remember from a dynamics class. Inline 4 stroke 6 cylinder engines (and the derivatives like a V12 or V6 2 stroke) are mathematically balanced in all axis.

What we need is a V12 diesel! Oh wait, replacement cost on 6 injectors is already too high.

[vintageracer]

I have a 2001 Chevrolet 1500HD Crew Cab Shortbed with an aluminum head 6.0 gas LS engine and electronic overdrive transmission.

This truck just rolled 331,000 miles this week with the original engine still running properly with NO problems. Transmission has been built once. Oil last changed 1,700 miles ago and the oil level is still on the full mark. Oil usage still none to very little between 5,000 mile oil changes. I run synthetic oil in this gas truck.

I also have a 1995 Powerstroke Crew Cab I purchased new that now has 198,000 miles. Again maintenance is the key. I run regular Rotella T in this truck. Just like the gas truck the transmission has been built once and the original engine has never had the valve covers off. Still runs great however what was once the top dog in the diesel truck market compared to the new diesel offerings from the big 3 today is woefully under powered!

Both trucks serve their intended purpose well!

Do the proper service and maintain your vehicle gas or diesel and you will get LOT'S of miles out of either one. Just make sure you buy the right vehicle for your intended use as there is NO one perfect vehicle for every intended use!

[ALANSD]

so True Mike, I drive Ford gassers, and am religious about maintenance. Just had transmission flush and refill at 148,000 ..Hoping to hold off the inevitable trans replacement. Oil changes at every 5,000.
Not too much to handle, it makes life a lot easier having a reliable vehicle.
I would like a diesel, but had a F250 1996 model and truly did not like it.

[GettinAway]

The old Toyota landcruisers has straight sixes in them. We were never able to wear one out. Never even had to put a wrench one one. All had well over 200,000 miles.
One thing about them though, they got terrible gas mileage. My 4.0 jeep engine was the same. Ran great, but poor mileage. Is there something about a straight six that makes it bullet proof, but fuel innefficient? I have no clue.. Sorry, I'm also way off topic. I don't know if I'll ever go to a diesel. Just seems like too expensive to maintain. I like to keep a vehicle for a long time.
Jeff

[dznf0g]

Originally Posted by GettinAway

The old Toyota landcruisers has straight sixes in them. We were never able to wear one out. Never even had to put a wrench one one. All had well over 200,000 miles.
One thing about them though, they got terrible gas mileage. My 4.0 jeep engine was the same. Ran great, but poor mileage. Is there something about a straight six that makes it bullet proof, but fuel inefficient? I have no clue.. Sorry, I'm also way off topic. I don't know if I'll ever go to a diesel. Just seems like too expensive to maintain. I like to keep a vehicle for a long time.
Jeff

Yes there is...and I am not knocking them at all. I also had an FJ40. That six's design and rights belonged to GM. The old Chevy 235. Toyota purchased the rights and design because the 235 was used very heavily, globally, in everything from tractors to trucks and construction equipment. Smart move on Toyota's part, as many brands of parts bolted up to it and scavenged parts could literally be found in the middle of the desert.

A six cylinder has very long crankshaft, rods and camshaft. As such they have a lot of rotating and reciprocating mass. That spell out a fuel economy penalty. Also they have a very long block and a much greater quench area. (the amount of surface area for heat to escape from the combustion chambers to the cooling system). That spells out much more waste heat escaping to the atmosphere and not used for motion. Another fuel economy penalty.

But the ability of a tall block and long crank throws allows for a longer piston stroke, and thus more torque capability out of an inline engine per cu. in. of displacement.

Now, mind you, those are the mechanicals. Modern electronics and fuel delivery components can "cheat" the physics somewhat, but the physics still applies.

[slowmover]

4.0L in our 2001 2WD XJ Cherokee capable of 20+ mpg at around 65-mph. EFI really made a difference.

The other straight sixes I've had weren't quite thirsty, but never quite economical, either. They were meant to be cast iron reliable. That usually means FE takes a hit as the mechanical fuel delivery was as unsophisticated as possible for a given era.


1990 35' Silver Streak
2004 555 Cummins

[m.hony]

Originally Posted by dznf0g

Yes there is...and I am not knocking them at all. I also had an FJ40. That six's design and rights belonged to GM. The old Chevy 235. Toyota purchased the rights and design because the 235 was used very heavily, globally, in everything from tractors to trucks and construction equipment. Smart move on Toyota's part, as many brands of parts bolted up to it and scavenged parts could literally be found in the middle of the desert.

A six cylinder has very long crankshaft, rods and camshaft. As such they have a lot of rotating and reciprocating mass. That spell out a fuel economy penalty. Also they have a very long block and a much greater quench area. (the amount of surface area for heat to escape from the combustion chambers to the cooling system). That spells out much more waste heat escaping to the atmosphere and not used for motion. Another fuel economy penalty.

But the ability of a tall block and long crank throws allows for a longer piston stroke, and thus more torque capability out of an inline engine per cu. in. of displacement.

Now, mind you, those are the mechanicals. Modern electronics and fuel delivery components can "cheat" the physics somewhat, but the physics still applies.

I've often heard the awesome 5.7 engine in my Tundra was bought from GM- the old 350- not sure how true it is. Worth a Google search I guess.
Apparently it is a myth that GM sold their 5.7L design to Toyota as the 2 engines are completely different.

[dznf0g]

Originally Posted by m.hony

I've often heard the awesome 5.7 engine in my Tundra was bought from GM- the old 350- not sure how true it is. Worth a Google search I guess.
Apparently it is a myth that GM sold their 5.7L design to Toyota as the 2 engines are completely different.

Myth....!

[m.hony]

https://www.youtube.com/watch?v=aKIC...em-subs_digest

[GettinAway]

Haha! 2500 HP!
Thanks dvzf0g, for the info on the old Landcruiser in line six. I had always heard it came from a GM design, but was made with tighter tolerances. Not sure about that last part.
We used to pull our huge pop up with a older Landcruiser. Two canoes on the roof of the cruiser, five bikes on the pop up, and grossly overloaded. I'd have a tough time holding 2nd gear going over some of the Colo passes. Just used to torture the engine and transmission. Took it over Imogene pass one day. Went anywhere, but we didn't drive by many gas stations without stopping. Ha

[dznf0g]

Originally Posted by GettinAway

Haha! 2500 HP!
Thanks dvzf0g, for the info on the old Landcruiser in line six. I had always heard it came from a GM design, but was made with tighter tolerances. Not sure about that last part.
We used to pull our huge pop up with a older Landcruiser. Two canoes on the roof of the cruiser, five bikes on the pop up, and grossly overloaded. I'd have a tough time holding 2nd gear going over some of the Colo passes. Just used to torture the engine and transmission. Took it over Imogene pass one day. Went anywhere, but we didn't drive by many gas stations without stopping. Ha

I don't know about the "tighter tolerances" part. The 237 (Toy had a slightly different head design which gained 2 Cubes over the out of production Chev 235) rattled like an old sewing machine....but was absolutely bullet proof, as was the 235.

I do know that Toyota's castings had a higher nickel content than the 235, and arguably had more resistance to wear in the cylinders than the 235. Valves and valve seats were a common issue with the LC though. Fortunately, I was then in my "advanced engines" class at the time and had full access to the university shop and machine shop. That was at about 70K. Normal for that generation of LC.

[abone]

My brother and I each had twin '74 FJ40's, same colour, identical trucks when we were in our early 20's. Man we had fun with those trucks, they were beasts.
We both had to do the valves at around 40,000 miles, rust issues and poor fuel economy. Wish we still had them, they are collectors trucks now.

[dznf0g]

Yup, mine was a 73. Pulled a lot of big blocks out of the mud holes with that "little engine that could" Rust was horrible. By 60k, there were holes in the rear 1/4 's. Let in a lot of exhaust fumes.

[lostcomma]

Originally Posted by m.hony

Lackluster payload, economy, power, towing capacity and high price-
The Titan has never been a game changer or even in the game- not even a player.

Extremely disappointing news about the new cummins in the titan. The Gas version of the HD titan actually out performs the diesel in almost every category with only about a 10% loss in fuel economy. That isn't all that bad as diesel seems to average a high cost over the last 10 years. I do know that the gm's have always been consistently the best in one performance category for over a decade and that is in going downhill. They have engine braking down to an art.
If you look at the cost factors of purchasing and owning a diesel truck it really doesn't make sense, so why do people buy them to pull around a realtively light airstream. It's about percieved performance, comfort and of course image. If you look at a corvette as a car, it gets poor mileage, it can get hung up pretty easy because it's low to the ground, it's noisy, has really crappy storage and if the one leaf spring breaks in the rear suspension your toast. Funny they still sell lots of them.
I would definitely buy a 3/4 ton diesel if I had the money, they are much quieter underload, are heavier so less of the tail wagging the dog, easier downhill in the braking dept. and are mighter in the numbers racket.

[crispyboy]

Originally Posted by lostcomma

If you look at the cost factors of purchasing and owning a diesel truck it really doesn't make sense, so why do people buy them to pull around a relatively light airstream. It's about percieved performance, comfort and of course image.

As to your last sentence: NO, YES and NO.

I bought my particular truck because it was engineered to do the job for which it is being used - mainly towing and hauling duties plus long trips. It is comfortable enough that I would much rather drive it than a car.
There is no perceived performance about it. Braking - while a diesel 3/4 ton has the same brakes as a gas 3/4 ton the diesel will control the load with the use of the exhaust brake and much less use of the service brakes. Acceleration for merging into traffic and maintaining on hills - diesel torque makes the drive easier and safer - I can merge in heavy traffic, keep up with traffic without being a hinderance or pass a slow truck on an incline.
A gas truck will pull any Airstream trailer made just fine but the diesel truck will out perform in every category as the load gets bigger. Less than 27' AS go gas 1/2 ton - larger than 27' go diesel if you can swing it.

[Toutsi 1957]

Originally Posted by lostcomma

Extremely disappointing news about the new cummins in the titan. The Gas version of the HD titan actually out performs the diesel in almost every category with only about a 10% loss in fuel economy. That isn't all that bad as diesel seems to average a high cost over the last 10 years. I do know that the gm's have always been consistently the best in one performance category for over a decade and that is in going downhill. They have engine braking down to an art.
If you look at the cost factors of purchasing and owning a diesel truck it really doesn't make sense, so why do people buy them to pull around a realtively light airstream. It's about percieved performance, comfort and of course image. If you look at a corvette as a car, it gets poor mileage, it can get hung up pretty easy because it's low to the ground, it's noisy, has really crappy storage and if the one leaf spring breaks in the rear suspension your toast. Funny they still sell lots of them.
I would definitely buy a 3/4 ton diesel if I had the money, they are much quieter underload, are heavier so less of the tail wagging the dog, easier downhill in the braking dept. and are mighter in the numbers racket.

You are absolutely right a diesel is more expensive to drive and buy than a gas engine if you do less than 25000 miles a year. If you can afford a Diesel go for it. If you do more than 25000 miles think about it. If you do more than 30000 miles a year, go for it.

[pappy19]

All those miles you listed, especially saying that 30,000 miles a year warrants buying a diesel, is silly. Today's gas engines can go 200,000 with no problem with decent maintenance. In actuality diesel engines start having their own problems after their 100,000 mile warranty runs out. Many things start to go bad that are very expensive on a diesel. Gas engines don't have much to go bad other than spark plugs or a water pump. Again, you don't need a diesel to haul your Airstream, you just want one.