Diesel or Hemi ?

[Rossum]

That just isn't true. I'm not sure where that myth came from. You'll get better mpg with diesel whether your on hwy or city. The only thing thats kind of a pain is if you do a lot of short drives, you'll want to run the engine for a minute or two so your turbo can cool. If diesel didn't make sense in city then why would school busses, ambulances, tons of cars across Europe, all be diesel?

Better fuel economy regardless how they're run? Sure. A diesel engine is intrinsically more efficient due its higher compression ratio. This is aided and abetted by the fact that diesel fuel has a higher energy content per gallon than gasoline does.

But the other pain the you've neglected to mention is clogged up DPFs and EGR systems when they're run on short drives and/or at low speeds all the time. This is a real problem for modern diesels used that way.

 

[2wd]

I was left stranded on the highway a hundred miles from home thanks to the CP4 pump in my last diesel. Thankfully the $10,000 dollar repair bill was handled under warranty. I would never consider a diesel with that pump, which limits me I think to a pre-2019 Cummins (CP3) or a New Duramax (Denso) if I wanted newer diesel.

It's unfair thanks to EPA but gas engines now adays can go hundreds of thousands of miles replacing regular wear items and doing regular maintenance. No EGR, DPF, SCR. The Hemi is an old tried and true design. Good old pushrod and port injection. Notice how Ford went back to this design with their very cool new 7.3 gas engine.

BTW you don't have to run 89 or 91 in your Hemi. It runs perfectly well on 87. It's recommended, not required, to run 89. You may get a few HP less on 87 as the timing is adjusted. I run 89 only when towing heavy. Otherwise I'm on 87 with no issues at all.

 

[rlc2020]

^^^^ This^^^^

You can't compare diesel prices to premium, compare it to 87. I've been running both of my Hemi Rams on 87 since 2016 and get great mileage and have had no issues. 87 is cheaper than diesel just about everywhere. That changes the equation quite a bit.

I average 17/tank and over 24 on highway trips at 72mph on 87 octane

 

[Bas]

87 is still considered mid grade here but that is good to know. Larger tank is a must for either one I have learned reading the forums here.