For my two cents worth...
I had a 2003 Silverado 2500HD with the 8.1 liter gas engine. I used it to tow my 24' toy hauler for many years (>10K weight loaded). It would bog on the hills at times, but never failed me. However, the mileage was horrible. 4-8 towing this trailer.
I then bought a GD 303RLS, which is 34' and a 5th wheel. The truck really struggled with this on long steep grades. And mileage was 4-8 mpg still.
Then I bought a 2020 Silverado 3500 HD diesel. This truck pulls no problem (even on steep grades). It will actually pick up speed on the hills if I give it gas (or should I say diesel). My truck keeps track of the trailering mileage and the average is currently 9.4 mpg.
So my experience between gas and diesel is night and day. The diesel beats gas hands down. At least for me it does. My RV buddies are also towing exclusively with diesel rigs, Ford, Dodge, and Chevy of varying years and swear by them.

I don't doubt that a modern diesel is superior to gasoline when looking at torque and towing capacity. But the primary question is will he be able to tow a 9-10K trailer up some fairly steep hills without severly limiting the towing speed. Probably about an 8% grade max.

He's trying to stay within budget which means he could purchase a low milage 2019-2020 gasser for the same price he'd spend on a 2014-2015 diesel in order to pay cash. If the gas truck will do the job adequately 3-4 times a year, then the decision is a no brainer. So we're really looking at anyone's experience with a 2017 or later gas truck that has been used to tow on some steep grades.

Jim

Tony,

The new gas engines were not designed to compete with engines such as your Duramax, but rather to fill the gap with an industrial rated engine between light duty and the HD diesel. This is based on usage, terrain, initial cost, cost of ownership etc.

The light duty diesel is another option for us half ton folks and likewise depending on the situation.

Jim

I have stayed out of this conversation because my experience doesn't really fit the original question . . . but, I feel that I need to respond to the perspective voiced in post 16.

I have also towed a Reflection 303RLS (for over 5 years and 25,000 miles) with a gasoline engine. Albeit . . . a turbocharged gasoline engine, but of much smaller displacement that the other engines being discussed. I am a firm believer that turbocharging is right for gasoline, just like it is for diesel. I have never experienced the lack of performance and fuel economy described in post 16. I don't tow the Rockies, but I do tow the Appalachians and have never had the powertrain even struggle to maintain 60 MPH. Across all those 25,000 towing miles, fuel consumption has averaged about 9.5 MPG. Those who do tow in the Rockies with an Ecoboost have stated that engine power is the same at 10,000 ft as it is at sea level. (which is what Ford claims).

A thousand lb-ft of torque might be nice to have, but is totally unnecessary for towing a 10,000 lb trailer (in my opinion). 450 lb-ft with a broad turbocharged torque curve does just fine.

Rob

Everybody's perspective and experiences are different Rob. Do I "need" 1,050lb-ft of torque in my truck to tow my 310GK? Nope. I could do it with 300. In my case, I spent many years towing boats and trailers with "underpowered" tow vehicles that did fine on flat roads but struggled going over mountain passes. I don't like it when my engine is screaming and I'm not able to maintain speed on steep grades. It's stressful and can be dangerous. It brings back a lot of bad memories that my kids even remember to this day. I actually look forward to steep grades now because the towing experience is exactly the opposite of what it used to be. It's effortless, quiet and completely stress free. It literally puts a smile on my face. I can pass anybody I want with ease - and I mean with ease that is difficult to comprehend considering I'm pulling 15,000lbs.

So I would much rather have extra power that I rarely use than the other way around. I'm just glad we have options for both camps. I know you're really happy with your truck and I'm happy with mine. Very different trucks that both suit their owners just fine. There is no right or wrong. Just different.

bertschb

Hi Brian,

I think that the message from this thread is that we shouldn’t judge current gasoline powertrains based on experience with gasoline powertrains from a decade or more ago. They are not the same.

My engine revs up but doesn’t “scream at me”. I have never not been able to maintain 60 MPH on grades. (I admit that I have never driven the Rockies and probably never will). My engine and trans temperature gauges never move more than a needle’s width higher on the steepest Appalachian grades on the hottest days.

Agreed that there is no right or wrong. Just different. Consideration must also be given to the majority of miles (95% in most cases) that are “not towing”.

Rob

Hi Rob,

I wasn't dissing your gas rig. Sorry if that is the way I came across. Just stating my experience with my gas vs. diesel. I would imagine the newer gas rigs are much better, especially if turbo (mine was not). My 2003 Chevy had the 8.1 liter fuel injected engine and Alisson tranny. That is almost a 500 cubic inch engine. I would have thought that engine more than enough to pull a toy hauler or my 5th wheel. At least that was my intent when I ordered that truck. But the engine would really scream to try to keep speed on steep grades. My toy hauler was heavier than my 5th wheel, but actually towed easier than the 5th wheel, perhaps due to the increased wind resistance of the 5th wheel. My steep grades are into the more remote areas of the Sierra in California to access the areas we promote hare scramble races. These are back country roads that can get steep. My diesel actually picks up speed on these same grades.

I would also imagine that mileage has gotten better on all the newer rigs.

My truck is used mostly for towing. I use my street bike or our Tahoe for work commute or around town. So diesel makes sense for me. I get 22 mpg on the highway with the diesel without towing, though.

As you said, no right or wrong, just different.

Tony