Diesel vs Gas cost to own comparison tool

Rozz522 · October 28, 2020

I wondering if anyone out there could recommend a calculator or comparison tool for comparing the per mile or fixed year interval cost of ownership of a diesel vs gas model truck. I've read a lot of online comparisons which looked at purchase price, fuel cost, maintenance costs, etc but while it's easy to understand the fuel economy of the diesel will be better but how do you quantify that along with everything else. I was thinking of creating a spreadsheet but figured I can't be the only one looking for this type of tool.

Ray Pickle · October 28, 2020

I think you may be over analyzing this. If incidents of repairs are roughly equal, although I believe due to def issues they are not, labor costs are higher on diesels. Preventative maintenance is higher. According to the diesel forum on this site def usage varies greatly due to use and maybe driving style but seems to fall between 300 and 700 mpg. As you have already stated acquisition costs are greater for diesel. If you tow heavy often, you will be happier with a diesel regardless of any cost differences. If you only occasionally tow heavy and/or significant mountain terrain, gas is fine and will save you money. At the moment diesel fuel costs are down from historic numbers bringing this calculation much closer but it still weighs in favor of gas and if diesel fuel goes back to what it had been over the past 3 or 4 years its not even close.

redwngr · October 28, 2020

Are you interested in comparing your 1500 gasser with a 3.0L or with an HD and the 6.6L? (or the canyon/colorado 2.8L)

If so, which engine are you running?

Daily driver duties or towing duties?

Lots of steady speed driving or lots of stop and go around town?

I keep reading posts about 'extra' cost for maintenance of a diesel, but would argue that any differences will not make a significant impact on the cost per mile of ownership.

Edited October 28, 2020 by redwngr

Rozz522 · October 28, 2020

1 hour ago, Ray Pickle said:

I think you may be over analyzing this. If incidents of repairs are roughly equal, although I believe due to def issues they are not, labor costs are higher on diesels. Preventative maintenance is higher. According to the diesel forum on this site def usage varies greatly due to use and maybe driving style but seems to fall between 300 and 700 mpg. As you have already stated acquisition costs are greater for diesel. If you tow heavy often, you will be happier with a diesel regardless of any cost differences. If you only occasionally tow heavy and/or significant mountain terrain, gas is fine and will save you money. At the moment diesel fuel costs are down from historic numbers bringing this calculation much closer but it still weighs in favor of gas and if diesel fuel goes back to what it had been over the past 3 or 4 years its not even close.

I'm sure I am probably overthinking it but based on all the advice you hear from everyone willing to offer it, I was looking for something very concrete and all encompassing. Some from the diesel crowd will tell you that if you tow anything, even the smallest load, that you will not be satisfied with the gas job. Others will say that the resale on the diesel over the gas will justify the extra cost. Others will claim a 50-100% increase in MPG for the diesel vs gas. It's all just very subjective, and while there may be a grain of truth with some of these opinions, they are easily inflated or twisted. I've read a lot of your posts and would say that your experience certainly has me thinking the gas would be more than adequate for my needs. For further point of reference, I am an engineer, so I tend to over analyze everything.

kenny_r · October 28, 2020

Tbh I own a gas HD and I could sell it for what I bought it for 3 years ago. I don’t believe in the whole “diesel gets way better resale any day over a gas truck” I think the numbers are relative it’s just that your paying the extra up front for the diesel, but you get it back at the end.

Rozz522 · October 28, 2020

1 hour ago, redwngr said:

Are you interested in comparing your 1500 gasser with a 3.0L or with an HD and the 6.6L? (or the canyon/colorado 2.8L)

If so, which engine are you running?

Daily driver duties or towing duties?

Lots of steady speed driving or lots of stop and go around town?

I keep reading posts about 'extra' cost for maintenance of a diesel, but would argue that any differences will not make a significant impact on the cost per mile of ownership.

I'm looking to upgrade from my truck to the HD platform and I'm was referring to comparing the costs of the 6.6L gas to the 6.6L Duramax. I generally keep a truck for 10 years and average 12-15k miles a year, so I was trying to find something where you could plug in the variables (cost of vehicle new, MPG of each vehicle, miles per year, towing miles, average yearly maintenance cost, anticipated resale value etc). That may also help with determining break even points, etc (like if I own the truck 5 years gas is cheaper, but if I own it 10 years diesel is). I understand there are a lot of variables, but when you look at if from a fleet perspective, I would be surprised if they aren't doing this level of detailed analysis.

To answer your other questions, yes this would be a daily driver, unloaded, with a round trip total of 250miles/week. That is a mix of 10% in town, 45% rural (45-55mph) and 45% interstate (70-80MPH). I tow an 8000lb loaded travel trailer for 10-12 trips a year. Usually we stay within a couple hours of home so lets say 3000 miles per year towing the camper. Additionally, I know the 8k lbs is no problem for this vehicle whether gas or diesel, but I need the extra payload, that why I'm going HD.

diyer2 · October 28, 2020

My father in law was a along time gas truck owner. Towed occasionally. Heaviest was a travel trailer. When he got a diesel truck he was grinning from ear to ear when he towed the camper. After a few years owning the diesel he missed the gassers lower cost and easier maintenance. Still enjoyed towing with the diesel.

We live in Colorado so the mountains are trying on tow vehicles.

If flat land occasional towing a gas would be my choice.

Rozz522 · October 28, 2020

8 minutes ago, kenny_r said:

Tbh I own a gas HD and I could sell it for what I bought it for 3 years ago. I don’t believe in the whole “diesel gets way better resale any day over a gas truck” I think the numbers are relative it’s just that your paying the extra up front for the diesel, but you get it back at the end.

See, you are sort of making my point for me. Is there any truth to this subjective observation, the diesel resale, not your observation. If I run NADA for the two trucks over the last 5-10 years, is that all it equates to, the difference in resale is equal to the difference in purchase price? I guess I just figured that someone out there must have done this analysis for all of these factors and come up with a tool.

Rozz522 · October 28, 2020

6 minutes ago, diyer2 said:

My father in law was a along time gas truck owner. Towed occasionally. Heaviest was a travel trailer. When he got a diesel truck he was grinning from ear to ear when he towed the camper. After a few years owning the diesel he missed the gassers lower cost and easier maintenance. Still enjoyed towing with the diesel.

We live in Colorado so the mountains are trying on tow vehicles.

If flat land occasional towing a gas would be my choice.

I'm in Maine, so I would describe most of my driving as rolling terrain. We do have some mountains in western Maine and I do tow through the White Mountains in NH, but obviously nothing like what you experience in Colorado.

diyer2 · October 28, 2020

This is discussed here frequently. Simple answer...... if one can afford the cost difference, go diesel.

Ray Pickle · October 28, 2020

I have been in automotive repair for 40 years, it by no means makes me an expert but experienced in my opinion. The usage you have described is perfectly within the gas trucks performance envelope and you will be happy with the money you have not spent! I have averaged right at 9 mpg towing a 12k fiver over 10000 mi. All across the country. Looking at reported diesel numbers posted on this forum hauling similar weights it looks like 10.5 to 12 is what most are reporting.

kenny_r · October 28, 2020

See, you are sort of making my point for me. Is there any truth to this subjective observation, the diesel resale, not your observation. If I run NADA for the two trucks over the last 5-10 years, is that all it equates to, the difference in resale is equal to the difference in purchase price? I guess I just figured that someone out there must have done this analysis for all of these factors and come up with a tool.

Some one did do an analysis on this site....I tried to remember what it was all about so I could track down the thread.

i82much · October 29, 2020

i am not aware of a tool but the NADA deal will get you the depreciation part. You can run the numbers fairly easily on the fuel economy part. Opportunity cost of tied up money and maintenance/repair costs are also relevant but harder to predict.

unit · October 29, 2020

Gasoline wins hands down for cost per mile and total cost of ownership. It's less expensive to purchase and cheaper to drive with the exception of those towing heavy most of the time. That said, buy the diesel if you can afford it! I drove the latest Ford and GM gasoline trucks before buying the Duramax and there is no comparison for power and driving satisfaction. My last truck was an 08 with the Duramax/Allison and this 10 speed transmission is the best trans I've ever driven. One caution: newer diesels don't like short trips - don't buy a diesel if most of your trips a less than 10 miles. Diesel emission systems work best and will give fewer problems if the truck goes far enough to reach proper temps and have time to function normally.

Edited October 29, 2020 by unit

Ray Pickle · October 29, 2020

Most "can" afford either. I would venture that for the majority the reason they can afford either is because they don't make a habit of wasting money on purchases that are superflous to the outlined need. It is why the majority of fleet companies purchase gas h.d. trucks. There is no debate which is more capable the question was can the gas provide the needs outlined. It obviously can.