Diesel or Gas?

[Trailboss]

Got a 96 7.3 F250 (bought new) with just under 400K. Only engine issue was the glow plug controller went out. Only smoke is light grey when starting, but clear underway. Consistently gets 18-19 mpg on the hwy at 65-70 mph, and 13 mpg when towing anything (empty 16' flatbed or 7000 lb horse trailer). Now probably needs injectors and glow plugs as it is hard to start and occasionally runs rough, but not sure if I want to spend $4 grand or so on a truck that will only be worth $4000 when done.

Just picked up a used 2001 Chev 3500 Express box van with 6.5 turbo pre-Duramax that gets 16.5-17.5 mpg on hwy, and 13 mpg towing (only 4500 lb flatbed so far). It's got the aerodynamics of a cinder block, but lots of pep and only has 50K mi. Making this one into a camper.

Got a bunch of heavy trucks (outside the scope of this discussion) with the big Cummins diesels, so I'm not pumping just one brand.

If you plan to tow a lot (say at least 20-30% of the time) and plan to keep your truck/van until it dies, I'd get a diesel. If you seldom tow, OR plan to get rid of your vehicle before it reaches 200K miles, I'd get a gasser.

 

[IdaSHO]

I'm not sure about the 7.3, but on my rig with the 6.0 psd with 35" tires and 4.10 gearing the best mileage is at ~2000 rpms.

Same goes for the 7.3

Revs beyond 2,000RPM and fuel mileage suffers.


One of the best "mods" I have ever done for my old 7.3 powerstroke pickup was regearing from 4:10s to 3:55s

Prior to re-gearing my empty highway fuel mileage (65-70mph) never exceeded 15 MPG. RPMs were roughly 2400

After re-gearing my empty highway mileage is flirting with 20 MPG at the same speeds. RPMs are roughly 1650

Add into the mix a good chip (stock injectors) and whatever power I feel like I lost prior to gears is back 150%, and I retain the higher fuel mileage.


Toss the camper on it, running right about 10,000lbs, we routinely knock down 15+MPG

So now it gets the same fuel mileage with the camper loaded as it did empty when stock.

I call it a win. :ylsmoke:

 

[Bbasso]

Chris @ ujoint wouldn't own another 6.0 PSD. I'm very sure of that.
As for tire size, I'm also sure he'd run any size he wants and be happy with it.

 

[Jsweezy]

Same goes for the 7.3

Revs beyond 2,000RPM and fuel mileage suffers.


One of the best "mods" I have ever done for my old 7.3 powerstroke pickup was regearing from 4:10s to 3:55s

Prior to re-gearing my empty highway fuel mileage (65-70mph) never exceeded 15 MPG. RPMs were roughly 2400

After re-gearing my empty highway mileage is flirting with 20 MPG at the same speeds. RPMs are roughly 1650

Add into the mix a good chip (stock injectors) and whatever power I feel like I lost prior to gears is back 150%, and I retain the higher fuel mileage.


Toss the camper on it, running right about 10,000lbs, we routinely knock down 15+MPG

So now it gets the same fuel mileage with the camper loaded as it did empty when stock.

I call it a win. :ylsmoke:

If you were to swap in some newer dana 60 axles from a 99-04 would you suggest going with the stock 3.73 gearing as a good middle ground between the two?

Edit: I forgot to ask what tire size your running. So what tire size are you running?

 

[IdaSHO]

3:73 would be a great middle ground for most, especially if you are going with a bit larger tire than stock.

I run a tire that's a bit wider than stock (for added load capacity) but the diameter is very near stock.

Currently running a LT265/75R16 Load E Toyo AT2

Diameter is roughly 32", but with the 265 width, the load capacity is bumped from roughly 3,000lbs per tire to 3,400 lbs per tire.

 

[Jsweezy]

So it sounds like a 285/75/16 (3700 lbs capacity per tire) thats only an inch taller in that same tire with the 3.73, would be about the same as a 265/75/16 (3400 lbs capacity per tire) with the 3.55s. Maybe?

Thanks for your input!

 

[Jsweezy]

Over at the peaceful Sportsmobile Forum there are no gas vs. diesel threads allowed, for this reason. There are a million there, and here, which all usually end about where this one is, which is why the mods cut them off immediately when started. I'm hoping Expo will soon take a similar stance.

Quote from PO's original post: "I'm one of those "to each their own" guys and not trying to stir the pot."

PO's post answered by first responder, CaideN: "There's probably over thousands of discussion of this subject on many forums. I think ultimately it's personal preference."

Is our endless bickering going to end anywhere other than mostly like-minded folks devolving into enemies? This is no different than American politics!

You just have to do like I do. Wait for it to fully derail and then jump in asking questions about what its turned into ha ha.

 

[ujoint]

Ujoint, are you saying you would not own another 6.0 or a van on 37's?

I wouldn't own another 6.0 even though mine was fairly trouble free for over 100k miles. But, I bought it new and maintained it myself. I def would have a van on 37s! Maybe not my DD with little kids but def on a fun rig. V4 has 38s currently but will be going down to 37s soon. We've built some awesome driving vans on 37s, they always get more likes and comments because they look so tough.

As far as gear ratio/tire size there's a simple calculation to see where you need to be (or get you close) to optimize efficiency. Take the new tire size (we'll say 35") and divide by the stock size (say 30" for a 245) so that gives us 1.16. Multiply that by the stock gear ratio (3.73 is most common) and you have 4.32. That leads you with the decision to go two ways (or stock 4.30s depending on what axle you're swapping) 4.10 for more highway MPGs? Or 4.56 for a bit more pep?

Weight, lift height and geographic location needs to be considered too, if the van is heavy or towing I would go to 4.56 for sure. If not, 4.10. In the end it all boils down to how the van will be used and what the owner wants/needs.

 

[wgchristman]

Manufactures love diesels cause their profit margins are higher. The fuel company's love diesel cause their profit margins are higher. The goverment loves it cause they can tax you more. People blame the EPA but they are in bed with big business as all the departments of goverment. The maintenance shops love it cause well you know...its the profit margins....so everything about diesel costs more. With that said your Total Cost of Ownership on a depreciating asset will be higher. If it's mechanical it WILL fail gas, diesel or the unicorn. So when it fails what are the challenges associated with that item? Manufactures don't warranty Diesel engines any different than the gas versions. Gas mileage? Well ....30000 miles a year the difference is $1200 for 5 MPG gain. Towing... It's safer to tow at lower slower speeds especially if you don't do it for a living. The highway system is the most dangerous place to be in America best to slow down. Fleet managers across America use gas for vehicles 1 ton and below. Now if your looking for cool factor or you enjoy spending more on a depreciating asset then that's your hobby and enjoy.

 

[swedishSTile]

Late to the party but reading most of this thread I have one more thought that I didn't see expounded upon. Single fuel camper.

I bought a diesel so I could build the entire camper around a single fuel source, that being diesel. Diesel cooking, heating and hot water. No requirement for propane, finding it, filling it, maintaining it. Just fuel up at the truck stop and be on your way.

If that is not in your sights I would say buy a v10 gasser and not look back. It is quieter (massively so), simpler to maintain, and will likely cost you less over its lifetime in total cost of ownership than the diesel.

That said, the tuned 7.3L PSD is massively fun to drive. No one expects a giant van to be as fast as this thing is. In southern California it really upsets people. Between its size, how loud it is, how they think you are going to go slow up the hill so they pull out to pass on the right as you cruise up with ease. People wrinkle their noses at it in parking lots and shake their heads in disgust. I LOVE IT. A giant diesel van is kind of a middle finger to the hoity toity range rover consumer culture here. Every time I see someone mouth "WHY" or "WHAT THE *******" as I drive by I smile ear to ear.

 

[derjack]

After a - feld- hundred years again a Gas vs. Diesel engine thread - seriously?

There are tons of discussions on that, even good ones. Why not reading these???

It all comes down on personal opinions and personal experience, nothing else. You will gain nothing if you know what I think is good. Same with my experiences.

Most important: The INTERNET > nobody will ever post anything IF the is nothing special to say. In other words: IF something fits anyone's expectations - he/she will not post/read this. Ergo you will only get feedback from people who are disappointed from their purchase! e.g. the "bad" 6.0 engines ...

 

[Bbasso]

I'm happy with each of my 7.3 and 6.8... no complaints.