gas vs diesel operating cost and mpg

94yj · February 20, 2020

i am thinking about buying a 2020 2500/3500hd regular cab for a service truck and wanted to ask if the cost of the diesel engine and the cost of fuel is worth it vs the gas engine what is the mpg for the both with a 3.73 rear axle also is the 4wd any extra upkeep as it will never see 4wd but it seems the 4wd are running about the same cost TIA

Edited February 20, 2020 by 94yj

buckwuk · February 20, 2020

Short answer, no. But do I still want the diesel, yes! For a service truck I'd probably go gas, better payload for tools and however your going to set it up. For the expense of the diesel and higher fuel and def costs mileage is never going to be worth it. Unless you tow a lot but even then I think the math is like 125k-150k miles before you break even. I'd think of it more as do I want the power/torque, exhaust brake for the extra 10k.

From what I see online is a lot of fleets are switching to gas. There info shows them over the life of the vehicle the cost of repairs and downtime far exceeds that of a gas motor.

Maintenance wise more oil so yes a little more expensive and a fuel filter every 30k. Or a lot of people do every other oil change. I dont think it's a big deal or that much of an expense if you do it yourself. If a dealer does it then I understand why people complain about maintenance on diesels.

Also new diesels apparently dont like to idle for extended periods of times with the emissions, not sure how you roll but I see service trucks idle forever it seems.

newdude · February 20, 2020

Nothing much on 4x4 other than front diff fluid and transfer case fluid that would need a changing at some point.

Diesel vs. gas depends on many factors. Are you mostly stop/go city driving or mostly highway? Would the truck be loaded at all times with gear/tools/supplies? Some sort of contractor cap with stuff in it?

Benefits of gas 2020 HD:

- No DEF.

- Can run 87 octane.

- Larger fuel tank on regular cab (36 gallon).

- Cheaper oil changes.

Cons of gas 2020 HD:

-Fuel mileage.

- "less power" (Depends on needs).

- 6 speed. Its a great unit, but the GM 10 speed exists.

Pros of diesel 2020 HD:

- Fuel mileage. Especially if you drive more highway than city.

- 10 speed.

- Power. Lots and lots of power.

Cons of diesel 2020 HD:

- Higher maintenance costs. Fuel filter, Trans system holds almost 10 quarts more, DEF, etc.

- DEF, DPF.

- Smaller tank. 28 gallon on regular cab.

- Cost of diesel vs. 87 octane.

- DPFs don't like idling.

- Regens.

Edited February 20, 2020 by newdude

94yj · February 21, 2020

19 hours ago, newdude said:

Nothing much on 4x4 other than front diff fluid and transfer case fluid that would need a changing at some point.

Diesel vs. gas depends on many factors. Are you mostly stop/go city driving or mostly highway? Would the truck be loaded at all times with gear/tools/supplies? Some sort of contractor cap with stuff in it?

Benefits of gas 2020 HD:

- No DEF.

- Can run 87 octane.

- Larger fuel tank on regular cab (36 gallon).

- Cheaper oil changes.

Cons of gas 2020 HD:

-Fuel mileage.

- "less power" (Depends on needs).

- 6 speed. Its a great unit, but the GM 10 speed exists.

Pros of diesel 2020 HD:

- Fuel mileage. Especially if you drive more highway than city.

- 10 speed.

- Power. Lots and lots of power.

Cons of diesel 2020 HD:

- Higher maintenance costs. Fuel filter, Trans system holds almost 10 quarts more, DEF, etc.

- DEF, DPF.

- Smaller tank. 28 gallon on regular cab.

- Cost of diesel vs. 87 octane.

- DPFs don't like idling.

- Regens.

thank you great info and i do idle the truck every once in a while for the warning and other lights at night as needed and the idle on the diesel is something i did not know about

94yj · February 21, 2020

19 hours ago, buckwuk said:

Short answer, no. But do I still want the diesel, yes! For a service truck I'd probably go gas, better payload for tools and however your going to set it up. For the expense of the diesel and higher fuel and def costs mileage is never going to be worth it. Unless you tow a lot but even then I think the math is like 125k-150k miles before you break even. I'd think of it more as do I want the power/torque, exhaust brake for the extra 10k.

From what I see online is a lot of fleets are switching to gas. There info shows them over the life of the vehicle the cost of repairs and downtime far exceeds that of a gas motor.

Maintenance wise more oil so yes a little more expensive and a fuel filter every 30k. Or a lot of people do every other oil change. I dont think it's a big deal or that much of an expense if you do it yourself. If a dealer does it then I understand why people complain about maintenance on diesels.

Also new diesels apparently dont like to idle for extended periods of times with the emissions, not sure how you roll but I see service trucks idle forever it seems.

thank you looks like i will be going with the gas version

CRApex · February 21, 2020

Any rumors on if the gas version would get the 10spd for 2021? That 'might' get me thinking about the gas motor next time around.

XY74 · February 21, 2020

The only thing I saw regarding rumors was some software updates to the camera system and a couple other minor tweaks. I think the 10 spd would help the gas engine a lot.

dieselfan1 · February 21, 2020

After the piss poor showing on the Ike Gauntlet they have to put the 10 spd. in the gasser. You can't get beat by 3 minutes in 8 miles and sit on your hands.

They need to get rid of Mr.Truck as the driver too. His name should be Mr. Ford.

ShotgunZ71 · February 21, 2020

The 10-speed in the gas would be completely useless towing unless GM gets the programming right and lets it downshift to keep the RPM in the power band before it's too late. That's why the Ike test was such a joke. Any normal, sane person would have put the truck in "M" and selected the top gear themselves, instead of letting the ECM/TCM do it. The 10-speed with more aggressive tuning would help, but if it's tuned more for economy instead of working, it'll be a waste.

When I'm towing in grades, I always lock out the upper gears so that it won't shift up too soon then try to "catch up" when the speed drops too much. Always easier to maintain speed than play catch up.

Ray Pickle · February 22, 2020

Shotgun you got it right. Issue is completley a programming strategy. Faulty strategy for a work truck in my opinion but correctable by proper user interface or programming update for those lacking the concept. 10 speed would be better due to less rpm drops between shifts. Reliabilty still leans to the 6 speed for me until more actual user miles are accumulated with the new 10 speed.

greatmizzou · February 22, 2020

If you got extra $$$ to blow diesel is the best platform. Its not necessarily cost effective, the break even point on a new diesel vs new gas is incredibly far off if not never achievable.

Ive been really impressed with the gas engine and most have spoke highly of it.

But again, if you can easily afford it diesel is clearly a stronger platform. When I shopped the diesel was about $10,000 premium. I would like it, but not that much. Plus I know nothing about servicing diesels

swathdiver · February 22, 2020

On 2/20/2020 at 2:44 PM, 94yj said:

i am thinking about buying a 2020 2500/3500hd regular cab for a service truck and wanted to ask if the cost of the diesel engine and the cost of fuel is worth it vs the gas engine what is the mpg for the both with a 3.73 rear axle also is the 4wd any extra upkeep as it will never see 4wd but it seems the 4wd are running about the same cost TIA

If all you need is 2WD, having 2WD will make maintenance and repairs easier down the road without that running gear in the way.

More importantly, is this for around town driving and towing or moving long distances? If the former go GAS, if the latter, get the DIESEL.

redwngr · February 22, 2020

22 hours ago, CRApex said:

Any rumors on if the gas version would get the 10spd for 2021? That 'might' get me thinking about the gas motor next time around.

If it gets a 10 speed, it won't be the one that's behind the diesel -- it's torque and duty cycle rating is much higher than necessary for the 6.6L gas.

I'd still not be surprised to see them replace the 6 speed with a 9 or 10 speed.

OTOH, there are about 18 (yes, 18) different versions of Allison 6 speeds in the 45/55/6500's...

Dunn · February 23, 2020

On 2/21/2020 at 12:17 PM, XY74 said:

The only thing I saw regarding rumors was some software updates to the camera system and a couple other minor tweaks. I think the 10 spd would help the gas engine a lot.

they want to sell diesel motors.....huge profits

10k upcharge and you get no credit for gas engine ( which you should be).....new diesel motors cost 5-7k

and for a manufacturer of vehicles they cost lot less....

so RAM, ford, GM kill it selling diesels to people.....they are way overpriced, 10k and no credit for gas motor they are replacing.....should be 5k max upgrade and they are still killing it

I am a gas guy, and yeah 10 spd would be awesome and how is 6.6 make less hp than their 6.2.....I don't think they really want to sell gasser HD trucks, certainly not easy to find

swathdiver · February 23, 2020

7 hours ago, Dunn said:

... and how is 6.6 make less hp than their 6.2.....I don't think they really want to sell gasser HD trucks, certainly not easy to find

Durability. 6.2s are not as enduring as the 5.3s and 6.0 HD motors.