Gas vs Diesel for Towing a Fifth Wheel!!!

[Taylor90]

I have some issues picking a suitable towing vehicle to haul a travel trailer. Gas vs diesel for towing a fifth wheel? Which one is better? Any suggestion?

[burningman]

3?!! I’ve had numerous old big-block gas Fords and Chevys and all got 5 to 7 while towing really heavy.
Something is wrong if you’re only getting 3.

[Goostoff]

I have a gasser. I get 3 MPG when I hook uop to the trailer. I think that explains enough.

[jaycocamprs]

rhagfo wrote:
LOL! Love comparing a 12 year old diesel to a new gas engine!!
Yes, pulling power of gas has come a long ways, but so has diesel even with the emissions gear!

5th wheels keep getting bigger, longer, and heaver, best choice is still a diesel for any 5er over 12,000#.

I'm with you. And the difference between a 05 LLY & a 18 L5P is like going from the 04 6.0 to the 05 6.6. I own a diesel DRW truck because I want to. I like having more truck than needed. If you need to justify the cost of RV'ing, you have the wrong hobby.

[burningman]

You have to look at more than what the book says the stock numbers are.
The book says my old Cummins only makes 420 ft/lbs and 215 HP. In reality, with a few relatively easy changes it makes twice that and if I want 700 HP, all I have to do is swap a couple more pieces. I probably will, just for fun.

I don’t think “which is better for towing a 5th wheel” can be answered without defining “better”.
Gas trucks generally can get the job done with a lower overall cost.
If you tow your trailer on the sand dunes, gas trucks are the only good option, diesels are too nose heavy and they plow in and get stuck too easy.
Whatever you hauled up a mountain with a diesel, someone did it before with an old gas truck. Just not as fast.
Diesels are generally more powerful, and a lot more fun to drive with a heavy load. You don’t really “need” all that power, but I sure do like it!

The exhaust brake on a diesel is a big plus coming down the mountains, but gas engines don’t need them as much because they make a lot more compression braking power on their own, they essentially have an “intake brake”. The reason diesels have so little compression braking is they have no throttle plate. Air is free to run right through them.
Gas engines are throttled, they get corked up at the intake, kind of like how an exhaust brake corks up a diesel at the other end.

I think everyone agrees the diesel is “better” at hauling heavy loads, but one of the reasons they go uphill better is you’re carrying a much lighter wallet.

You can’t compare to big-truck diesels. Some pickup diesels make as much power as many big-truck diesels. But the huge 15-liter big-truck motor is way understresswd. It COULD make a zillion HP. It’s detuned to where it can run full throttle uphill under a huge load all day long without even getting hot.
That’s why they go so many miles. But the truth is by 500,000 they’re usually pretty tired or have already been overhauled.

[Ark235B]

I pulled several trailers up many a mountain with a gas pickup. It was the day of driving across South Dakota on Interstate 90 with a 45mph headwind that made me switch. Spool up the turbo a bit and off you go with a diesel.

[DiskDoctr]

IMHO, there are a number of differences between gassers and diesels. Just like heated seats and 4WD, each person has to weigh the differences in THEIR situation. Do you NEED heated seats when you could just throw down an extra cushion? Buy what suits you.

5th wheel and camper towing is about more than weight. Frontal square footage and wind resistance are also big factors.

When we looked at upgrading our TV, we considered gas vs diesel and decided it didn't make sense to buy new for our needs.

I'm about $20k into a nice 2002 7.3L Ford Excursion in very good condition (rust free) with just a few minor issues (new seat leather likely later this year for about $1k), and I've already rebuilt the front end and performed most of the 200k service interval items, which we accepted as part of the initial costs, but now good for another 200k miles.

In that cost we have also been able to increase the output and decrease the stress by about 30-50%. Dialing in the last part of it now.

Will our next truck be a gasser or a diesel? Who knows. Just like OP, we'll evaluate it at that time, look at the differences and then decide what is best for us.

I think people who respond to threads like this try to include "Why we are happy with our choice of diesel or gas" - likely more helpful than simply stating the differences that often deteriorates into an academic exercise of "who is smarter about engines" LOL.

The opinions I respect most are those who approach it from the position of "This is my opinion and here are the facts and reasons why," rather than "I know best and anyone who doesn't agree is an idiot" 😉

Longevity, comfort, solid reputation, DIY-maintenance capabilities, superb towing capabilities, stress free travel, pride of "self-built and modified," LEV rating without all the expensive EPA garbage, loads of interior passenger and cargo space, and low initial and ongoing costs are key reasons we purchased our diesel a few years ago.

Cheers!

[DiskDoctr]

valhalla360 wrote:
Sorry if calling a use case that is multiple standard deviations from normal "silly" hurt your feelings.

Nope. Your choice of words are your responsibility. Rudeness and disrespectful comments belong to the author and a reader's "feelings" do not change that one way or the other.

Blaming others for your bad manners only results in repeat offenses.

And your claim of "multiple standard deviations from normal" is only your opinion and already shown to be wildly incorrect.

But you can continue to prop up your opinion using some fantasy million mile gas engine and repeated claims that at 200k all vehicles must be delivered to the scrap yard because they are worthless.

Of course you are also assuming no one would ever use a diesel for any other trips or purposes, just a few trips a year- except for Carnies in your words.

I guess you are also offended when anyone uses their trucks for transportation instead of towing a camper. How dare they put miles on their trucks :R

Taking a trip with 8 people in a large diesel SUV where everyone has lots of room and splits the fuel costs and spends time together as friends and family must really get your gut in knots. A thousand miles in a weekend? Oh the horror!

Guess what else. Some people even use their vehicles for work!

And you know what else. There are even folks who ENJOY driving their trucks and might even...gasp...drive them daily 😉

Say it ain't so, Joe. 😉

If it doesn't fit in your "opinion box" it must be due to someone's feelings or their silly ideas.

[lazydays]

rhagfo wrote:

4x4ord wrote:

4x4ord wrote:

lazydays wrote:
Since 2003 I've pulled different campers with a Ford 5.3l, Chevy 6.0l, Dodge V10, and Chevy 6.6l diesel. No way would I go back to gas. I've owned the diesel going on 7 years and have only put 42k miles on it so I very rarely use the truck. Mainly weekend driving and pulling the camper in the Summer. Cost of ownership means nothing to me or I wouldn't own a camper, boat, multiple cars, ect. Took my Dad who almost 70 when he finally realized that diesel was the way to go and he's on his second now.

You might find that there are some 2018 gassers that will tow nicer than your 05 Duramax does.

I want to put some numbers to my claim that a new gasser would out tow an old Duramax. The 2005 Duramax was capable of putting a maximum of 3500 lb ft of torque to the rear axle in 2nd gear. The truck at that point would be traveling 22 mph. The 2018 6.2 Ford equipped with a 4.10 rear axle can put nearly 4400 lb ft of torque to the rear axle in second gear. At that point the gasser would be traveling 41 mph.

While the trucks are running 60 mph on level ground where little power is needed both engines would be turning quite similar rpm. (The 2018 gasser in 6th vs the 2005 Duramax in high gear or 5th). The Duramax would be quite comfortable at 60 mph in 5th gear were as the 6.2 gasser might be requiring a downshift or two as soon as a bit of grade increase comes along.

LOL! Love comparing a 12 year old diesel to a new gas engine!!
Yes, pulling power of gas has come a long ways, but so has diesel even with the emissions gear!

5th wheels keep getting bigger, longer, and heaver, best choice is still a diesel for any 5er over 12,000#.

If my truck was stock I would agree. Point is I have no use for a gas motor and as long as I'm pulling a 12,800lb camper down the road it will be diesel for me.

[rhagfo]

4x4ord wrote:

4x4ord wrote:

lazydays wrote:
Since 2003 I've pulled different campers with a Ford 5.3l, Chevy 6.0l, Dodge V10, and Chevy 6.6l diesel. No way would I go back to gas. I've owned the diesel going on 7 years and have only put 42k miles on it so I very rarely use the truck. Mainly weekend driving and pulling the camper in the Summer. Cost of ownership means nothing to me or I wouldn't own a camper, boat, multiple cars, ect. Took my Dad who almost 70 when he finally realized that diesel was the way to go and he's on his second now.

You might find that there are some 2018 gassers that will tow nicer than your 05 Duramax does.

I want to put some numbers to my claim that a new gasser would out tow an old Duramax. The 2005 Duramax was capable of putting a maximum of 3500 lb ft of torque to the rear axle in 2nd gear. The truck at that point would be traveling 22 mph. The 2018 6.2 Ford equipped with a 4.10 rear axle can put nearly 4400 lb ft of torque to the rear axle in second gear. At that point the gasser would be traveling 41 mph.

While the trucks are running 60 mph on level ground where little power is needed both engines would be turning quite similar rpm. (The 2018 gasser in 6th vs the 2005 Duramax in high gear or 5th). The Duramax would be quite comfortable at 60 mph in 5th gear were as the 6.2 gasser might be requiring a downshift or two as soon as a bit of grade increase comes along.

LOL! Love comparing a 12 year old diesel to a new gas engine!!
Yes, pulling power of gas has come a long ways, but so has diesel even with the emissions gear!

5th wheels keep getting bigger, longer, and heaver, best choice is still a diesel for any 5er over 12,000#.

[4x4ord]

JIMNLIN wrote:

Taylor90 wrote:
I have some issues picking a suitable towing vehicle to haul a travel trailer. Gas vs diesel for towing a fifth wheel? Which one is better? Any suggestion?

Probable already mentioned but we have pages and pages of diesel vs gas over in the tow vehicle section. Usually mods/adm will move tow vehicle questions over there.....guess things are a bit slow in the 5th wheel forum.

Its really simple. Non of the gasser's can tow heavy trailers without lots of rpm and noise...and a diesel isn't necessary for a lighter weight trailer.
And if your trailer is between heavy and light weight then simply choose a gazz or a diezzul powered truck....in white of course 😉

It really is that simple. However 10 years ago a diesel was a huge improvement over a gasser for a 12000 lb Rv. Now a 12000 lb rv can be easily towed with a gasser. Most RVs are under 12000 lbs and most of us buying new diesels would have a pretty tough time justifying the need of one for our little trailers.

[JIMNLIN]

Taylor90 wrote:
I have some issues picking a suitable towing vehicle to haul a travel trailer. Gas vs diesel for towing a fifth wheel? Which one is better? Any suggestion?

Probable already mentioned but we have pages and pages of diesel vs gas over in the tow vehicle section. Usually mods/adm will move tow vehicle questions over there.....guess things are a bit slow in the 5th wheel forum.

Its really simple. Non of the gasser's can tow heavy trailers without lots of rpm and noise...and a diesel isn't necessary for a lighter weight trailer.
And if your trailer is between heavy and light weight then simply choose a gazz or a diezzul powered truck....in white of course 😉

[4x4ord]

4x4ord wrote:

lazydays wrote:
Since 2003 I've pulled different campers with a Ford 5.3l, Chevy 6.0l, Dodge V10, and Chevy 6.6l diesel. No way would I go back to gas. I've owned the diesel going on 7 years and have only put 42k miles on it so I very rarely use the truck. Mainly weekend driving and pulling the camper in the Summer. Cost of ownership means nothing to me or I wouldn't own a camper, boat, multiple cars, ect. Took my Dad who almost 70 when he finally realized that diesel was the way to go and he's on his second now.

You might find that there are some 2018 gassers that will tow nicer than your 05 Duramax does.

I want to put some numbers to my claim that a new gasser would out tow an old Duramax. The 2005 Duramax was capable of putting a maximum of 3500 lb ft of torque to the rear axle in 2nd gear. The truck at that point would be traveling 22 mph. The 2018 6.2 Ford equipped with a 4.10 rear axle can put nearly 4400 lb ft of torque to the rear axle in second gear. At that point the gasser would be traveling 41 mph.

While the trucks are running 60 mph on level ground where little power is needed both engines would be turning quite similar rpm. (The 2018 gasser in 6th vs the 2005 Duramax in high gear or 5th). The Duramax would be quite comfortable at 60 mph in 5th gear were as the 6.2 gasser might be requiring a downshift or two as soon as a bit of grade increase comes along.

[dougk53]

goducks10 wrote:
I don't look at it as a cost per mile thing at all. I got the diesel option cause I wanted it. Same as those who get the Laramie/Lariat option. How about the bigger screen on your radio? The fancier rims? etc. It'a all part of buying a car or truck. Just option it out like you want, drive it until your bored with it and get another.

This speaks volumes. It is not what is better towing a fifth wheel, it is what size fifth wheel you are going to tow and your personal preferences and comfort level.
We recently traded into a Ram 2500 6.4 Hemi to tow a 7700# TT. A diesel for us would almost never make sense as at our age trading out of a 2 year old TT that meets almost all our needs would make little sense just as $9000 for a diesel plus $.75 more per gallon for fuel in our area outweighs all other considerations.
We also lease our trucks now as we get new about every 3 years or less. Have owned vehicles with up to 400,000 miles on gas engines. Some will say leasing makes no sense but it does for our lifestyle, at least our trucks.
For us the cost difference for a diesel is better spent traveling. If you tow heavy diesel is the only option but it comes down to first your needs and second your wants and only you can determine those things.
Good luck.

Doug

[valhalla360]

deltabravo wrote:
Ask the guys that transport RVs from factories to dealers... rarely will one say "gas is better for heavy towing".

I did summer time transport in 2014 and 2015. DIESEL all the way, even though I wasn't towing heavy. Units I hauled were 21-25 feet most of the time. I had a very easy route too, with minimal change in elevation, but I still prefered diesel for that route.

Again, this is a commercial application where other things are driving the choice:
- Most will at least occasionally get a heavy trailer where they need that extra power to stay within the ratings. (you also dont' need a 1ton dually to pull a 23' trailer but most will have that)
- Most are doing a ton of miles towing where the fuel efficiency really makes a difference to the bottom line. They can amortize the upfront cost of the diesel with fuel savings.
- If you are putting 50k miles per year on a truck, in 10yrs they would be at 500k miles and yeah, they probably would be on their second gas engine and considering if they need a third.

By contrast your average RV buyer with a 23ft travel trailer:
- Doesn't need the diesel power due to weight limits.
- Usually only does a couple thousand miles per year and the fuel savings might buy a dinner out once a year. It will never cover the up front cost of a diesel. (I'm talking the big diesels not the new 1/2ton small diesels)
- Usually only does around 12,500 total per year giving 250k gas engine a 20yr lifespan, so either engine is good for the life of the truck.

[valhalla360]

DiskDoctr wrote:

valhalla360 wrote:
But given the available engines, the idea that a typical non-commercial diesel will outlast a gas engine by 2-3 times is just silly...

Of course, if you really are putting 500k miles on a pickup (maybe 50k/yr on the carnie circuit),

Listen, you're entitled to your opinion, but others are capable of making their points without being disrespectful or rude. Perhaps you could show similar courtesy to your fellow posters.

Google: Ad Ignominiam Diversion

It's an invalid argument to mock others' position and it is considered quite rude and often inflammatory.

Make your case respectfully or move along.

Sorry if calling a use case that is multiple standard deviations from normal "silly" hurt your feelings. Inflammatory would be calling you a name. This was highlighting an argument that is misleading.

Generally, cars & trucks are assumed to have a lifespan of around 20yrs and the average mileage per year is around 12,500...which works out to around 250k miles...which pretty much matches up with the life of a gas engine.

So if a gas engine lasts 250k miles...it already lasts the life of the truck. It's unlikely to have an engine replaced. Lasting long enough to get to the third engine is exceedingly rare.

I've seen a story a few times about a guy who has an old Volvo that at something like 1.5million miles but to claim it as justification to buy a new Volvo that is a completely different design is silly.

But let's say you do get to the point of having to replace the engine: A diesel runs $8-10k more up front. A replacement gas engine can be dropped in for around $5k-6k if you really do reach that point, so you are still ahead of the game and a 40yr old diesel is going to have negligible resale value in most cases (as will a 40yr old gas truck).