Should I switch to diesel?

[wrvond]

I'm not trying to start another gas vs. diesel thread, but need some real world anecdotal input.
We just completed a 1000 mile round trip from West Virginia, through the mountains, to Murrells Inlet, SC, and back, towing our new TT.
My 5.4 liter F150 4x4 pulled the Coachmen Catalina 253RK pretty well.
I was surprised that I was able to average about 50mph uphill (I expected I might have to push the rig up), but was very disappointed that I only got about 8mpg on average.
At 8mpg, I won't be able to afford to make many four day weekend trips of any kind of distance, I'm afraid.
So, I'm thinking of moving up to an F250 diesel, or similar.
Questions:
Is diesel really going to be enough of an improvement in mpg to justify the move?
Is diesel torque/towing going to be a quantum improvement?
What size engine should I be looking at? Is a 6L diesel going to "whup" the 5.7L gasser, or do I need something bigger than that?
Finances dictate a unit in the 8 to 10 year old range, do these pre-date DEF and other emissions requirements?
Are there any particular engines/years I should be wary of?
Are there any particular engines/years/models that are most desireable?
I'm sure none of these questions are new to you guys that have made the transition, and I look forward to reading your thoughts and experiences.
Thanks.

[tim_and_amy]

I skipped what everyone else wrote and will give my feedback based on my experience. I had a V10, now the thing about Ford engines are they are "cammers" or over head cams. They like RPM's, and Ford designed a SW flaw into the PCM. If you are at max throttle for too long the PCM will command the transmission to upshift, which will slow you down to about 20mph towing up hill. Very dangerous. Hence why I switched to a diesel.

The V10 gas also required Premium fuel, as you should use in any gas engine you are towing with. My mpg towing 8k lbs without premium was 7mpg, and with premium was 9mpg. Yes trailer in SIG.

Diesel, increased to 11.7mpg towing and this is in the western US with mountains.
The diesel also never slows down, if it does, put your foot in it and off it goes, you actually have to let off the throttle.

I am now on my second Ford 6.0L diesel, neither of which I have had any issues with.
But here is the truth.
The Ford 6.0L do get a bad wrap, the 03 and early 04 6.0L are the ones to stay away from.
If you are looking at fords, then also make sure it is stock or at least has an EGR cooler delete kit or upgraded EGR cooler. Don't confuse that with a full EGR delete. I just ordered my EGR cooler Delete and Oil Cooler kit for $170 from Amazon.
The EGR cooler basically will boil your coolant if your EGR valve starts sticking. You leave your EGR in place, but delete the recirc to it from the exhaust. It doesn't harm the truck nor change any puffer test at the tail pipe.
Also, the factory oil coolers were known to get sand casting material in them or get plugged. Because of the EGR cooler issue it can cause the coolant to boil and in the oil cooler this will plug up the oil/coolant passages. So generally if you go in to delete the EGR cooler, you just change the oil cooler too as it is right next to it.

Other things I avoid on F-series is I any one has ran a tuner on the diesel. Walk away, because the 6.0L was already hopped up and running near capacity for the head bolts.
Now, if some one, has modded the engines with the "improvements" that people do, head studs, egr delete and coolant filter, then a tuner is Okay.
The only people I know personally that have had head bolt issues are either the guys who didn't do coolant maintenance, which plugged up the EGR and Oil cooler causing the engine to heat up and pop a head gasket, or the guys running too high of tune on the engine.

Personally, after owning a GM truck, I won't go back, I like GM trucks, the room in the Fseries is much better.

things to also keep in mind, look for a late 04 up 6.0 or the newer trucks. most 6.0L trucks can be found for around 17K or less. A 2008 is usually around 22K.
Every MFG has had some issues here or there. If you really want to know facts, visit either the fordforums or the superduty or the powerstoke forums.

Also on a final note, the late 04 and later models had a different transmission set up. My 04 and 05 in tow mod engine brake, when going down hill if you tap the brakes the engine will automatically downshift, if you stomp on it hard it will downshift two gears, if you feel this isn't enough you can manually downshift. Even in the rockies I rarely had to use the brake pedal except on Cabbage hill above Pendleton Oregon.

[gtsum]

I am not getting into which one is more cost effective, but I will say I went from a 2013 Ram with Hemi to a 2014 Ram with Cummins and I couldnt be happier. yes it costs more, and maintenance will be more, but the mpg is certainly better, the trailers are not moving the truck around, and the overall towing experience is just plain better for me...and that is worth the additional cost to me. I didnt buy a 68k truck to worry about mpg's...I wanted a better towing machine and I got it.

The torque of a diesel is just a way different driving experience than a gasser...the gasser has more seat of the pants feel to it when you step on it, but the diesel builds power like a freight train....smoooooth...

[thomasmnile]

bfast54 wrote:
You know,.......this whole discussion,over FUEL MILEAGE.....,.. is rather Pointless....

In the grand scheme of things, probably true. Think this 'legend' was born mainly out of the days of steadily climbing gas prices and the arrival of diesel powered light trucks in the marketplace. Sure, diesels do seem to have a bit of an edge in fuel economy and for a fairly heavy truck it is impressive compared to some of the gas powered offerings. Biggest factor hurting diesel is the price disparity in fuel which wasn't always there, but now seems to be present in perpetuity.

Is it a deal breaker for most? Probably not. I'm towing an 'ultralite' TT now and certainly don't need a diesel to pull it, but the truck is paid for and if we're not traveling a tank of fuel can last the better part of a month. And no, the engine is not disintegrating in my driveway.

[bfast54]

You know,.......this whole discussion,over FUEL MILEAGE.....,.. is rather Pointless....

If FUEL MILEAGE ... is what you want.....need,..Buy a Hybrd PRIUS.AND STAY IN HOTELS.:S


However....that has major limitations......(Most hotels have little sense of humor,when you build a campfire,to do smores..in the hallway)

So,really,what it comes down to,is.......WHICH DO YOU WANT. Gasser,with enough power....or Diesel, with torque ......power to spare???????

We ALL know,pulling our house down the road, isnt going to get us 30,40,50 mpg.

[crcr]

The Texan wrote:

rhagfo wrote:


If you look at the repair cost for both DuraMax and Cummins they are much lower. Diesel is only 8 cents more than regular here in Oregon.

If you go from 8 mpg to 12 mpg that is 50% better mileage at 3.73 for reg, and $3.81 for diesel the difference is 8 cents 2% difference in cost!

I will not say that buying and using a diesel truck will be less costly in the long run, but the cost difference is far less that most gas lovers are led to believe!!

I bought used, 234,000 miles used! now at 271,000 and still pulling an 11,000# fiver STRONG, 11 to 12 mpg pulling in hills, 12 to 14 city driving, and 20 mph empty on the open road.

Drive to your east, across the ID state line and the difference between diesel and gas is 40¢± per gallon, so that blows your 2% out of the water. We travel many western states and OR has the best diesel price of any western state, right now. Most are at least 40¢ difference and I have seen 60¢ difference in the last month.

Price diff varies greatly by state. In AZ, right now, 23 cents more per gallon for diesel than regular gas.

[thomasmnile]

kaydeejay wrote:

ah64id wrote:
I thought that was pretty common knowledge? 5ers of the same weight/length always seem to do better on fuel than their TT counterparts.

This is news to me!
Having worked (a little) with aerodynamics in the auto industry I would have to see some side by side tests to completely accept your reasoning.
So while I'm not going to argue with you I'm not totally buying in either.

Not an engineer, (didn't even stay at a Holiday Inn Express last night) but here's real life anecdotal experience. We previously owned a HitcHiker ll/LS that tipped the scales a little over 12K loaded for travel. The HH was pretty much a flat front cap and well over a foot taller than our current bumper pull TT (Jayco WhiteHawk 27DSRL 7500 lb max weight). Both trailers towed with an '05 Ram 3500 at no greater than 60 mph. To date, I've not seen a difference in fuel mileage towing the TT over the fifth wheel, despite the huge difference in weight. I've concluded the aero drag with the WhiteHawk must be greater than the fifth wheel, but who knows...........

[kaydeejay]

ah64id wrote:
I thought that was pretty common knowledge? 5ers of the same weight/length always seem to do better on fuel than their TT counterparts.

This is news to me!
Having worked (a little) with aerodynamics in the auto industry I would have to see some side by side tests to completely accept your reasoning.
So while I'm not going to argue with you I'm not totally buying in either.

[AH64ID]

A 5er rides the displaced airstream of the truck, unlike a TT which has to move the air again. Similar to a canopy helping get better economy than one without for the same trailer. They are higher, but only one air disruption vs two.

I thought that was pretty common knowledge? 5ers of the same weight/length always seem to do better on fuel than their TT counterparts.

It's similar to how an extended length shank will have a noticeable decrease on economy. It's all about airflow.

Personally I have a friend that would get the same mileage towing a 22' TT vs his previous 30' 5er with a 2nd trailer behind it. The TT was approx 4Klbs, and the 5er with extra trailer was probably 3x as much weight, if not more.

[Sport45]

I don't have any experience with a 5'er, but I've read many accounts of the drag being no worse (or often better) compared to a TT of the same length and weight. Kind of makes sense the air flow over the cab continues up over the 5'er in a smoother fashion than it would with a TT.

[kaydeejay]

ah64id wrote:

If the OP counts on 50% better mileage they will be disappointed. You are running a 5er, which are better on fuel than TT's. You are also talking 62-65, not 65. While that seems minor it isn't in the wind game with a TT.

Diesel is more efficient, no doubt, but I wouldn't ever tell anyone to count on a 50% increase in mileage. I would buy 40% better on a good day.

I'm curious as to why you think a fiver is better on fuel than a TT - surely a fiver presents a higher frontal surface area, which translates into more wind resistance? :h

[AH64ID]

kaydeejay wrote:

ah64id wrote:
........................

#2 Diesel has 14% more BTU's than unleaded, so you will not see a 50% increase in fuel economy.

At 18-19K lbs GCW with my sig truck and trailer I get 9.5-11 at 65 depending on the winds and elevation change. The gas rigs I go camping with get about 7-8 at 5-7K lbs less weight, so there is a difference there. Cost per mile, not as much as mpg.

Gonna disagree with you on two points:-
While diesel has 14% more BTUs, diesel engines are much more efficient than gas ones due to the higher compression ratios. A comparable diesel will get a lot more than 14% better mileage.

Case in point - my rig is running in the 15K-16K GCWR range, so is slightly heavier than those gas trucks you quoted getting 7-8mpgs.
I consistently get between 12 and 13 mpg at 62-65mph. Looks like better than 50% to me!

If the OP counts on 50% better mileage they will be disappointed. You are running a 5er, which are better on fuel than TT's. You are also talking 62-65, not 65. While that seems minor it isn't in the wind game with a TT.

Diesel is more efficient, no doubt, but I wouldn't ever tell anyone to count on a 50% increase in mileage. I would buy 40% better on a good day.

[Tystevens]

zogg wrote:
However....there is a lot of extra cost to a diesel. My buddy's F250 had to be head studded at 80,000 miles, and needed new injectors....cost was almost $8000.
A neighbor had his turbos go bad on his 6.4 L Ford diesel....almost $10,000 with all of the associated repairs, and he was just out of warranty when it happened, so fairly low miles.

Well, there are significant extra costs to owning at least a certain brand! :S

Just kidding, of course.

But while the buy-in should be considered, the resale is also a lot higher. And as far as annual costs and maintenance, other than fuel, my maintenance was much, if any, higher on my Duramax compared to my 1/2 ton gassers. Oil changes were a wash (6 qts x 7500 miles vs. 10 qts x 10,000 miles). Most other maintenance was the same, and actually easier on the Duramax. The diesel was an extra $50 for a fuel filter each year, but that was about it.

[kaydeejay]

ah64id wrote:
........................

#2 Diesel has 14% more BTU's than unleaded, so you will not see a 50% increase in fuel economy.

At 18-19K lbs GCW with my sig truck and trailer I get 9.5-11 at 65 depending on the winds and elevation change. The gas rigs I go camping with get about 7-8 at 5-7K lbs less weight, so there is a difference there. Cost per mile, not as much as mpg.

Gonna disagree with you on two points:-
While diesel has 14% more BTUs, diesel engines are much more efficient than gas ones due to the higher compression ratios. A comparable diesel will get a lot more than 14% better mileage.

Case in point - my rig is running in the 15K-16K GCWR range, so is slightly heavier than those gas trucks you quoted getting 7-8mpgs.
I consistently get between 12 and 13 mpg at 62-65mph. Looks like better than 50% to me!

[AH64ID]

Diesel costs more to repair, costs more per gallon, costs more to buy, and I own one for a reason...

#2 Diesel has 14% more BTU's than unleaded, so you will not see a 50% increase in fuel economy. At 18-19K lbs GCW with my sig truck and trailer I get 9.5-11 at 65 depending on the winds and elevation change. The gas rigs I go camping with get about 7-8 at 5-7K lbs less weight, so there is a difference there. Cost per mile, not as much as mpg.

Diesel economy also takes a hit because now you can pull grades at 65+, where before you where at 50. Run the same speeds as before and the fuel savings will be much larger... but I doubt 1% of people do that.

I would steer as far as possible from a 6.0L Ford, or even the 6.4L.

If you have to go 8-10 years old you are going to want Dodge or GM for reliability, Ford just doesn't have it.

Anything 07.5 and newer will get lower fuel economy per hp than older trucks. Some of the newer DEF trucks are better than 07.6-10 but you have to add in the cost of DEF too.

Don't dwell too much on the displacement of the diesel engine, look at the power. A turbo does wonderful things with smaller displacement.