I don't think I have ever spent money on a vehicle under 100k that wasn't regular maintenance or and addition to the vehicle.

The 5.3L with a 6-speed doesn't do very well. Ram with an 8-speed should beat it in gas mileage easily.

Now the chevy 6.2L is another story, but I assume that's not part of the comparison.

Not sure what you are trying to say....Most vehicles I have owned required expense above regular maintenance the first 100k miles

Every Chevy my fathers owned has beaten my ram for mpg's. The 8 speed might make the hemi get better that the '13 and older ones with the 6 and 5 speeds, but it's still not going to beat a late model silverado for mpgs all things being equal.

but I owned a 5.3L for the last 12 years

I think where your wrong is with this statement. There have been some significant changes in the 5.3 in the last few years you have no experience with from your old 5.3. If your 5.3 was an '05 then it was before AFM which is comparable to MDS that dodge runs on the hemi. I believe AFM came out as an option in 2007 or so?

Also the 2014 plus got about a 40-50 hp bump and from what I hear get quite a bit better mpg than its predecessor.

Old Rams got terrible mpg - no doubt about that. Newer hemis with the 8-speed and a low-reduction rear axle are getting 19-21 on the hwy, and I don't think anyone with the 5.3L and a 6-speed is getting that.

Now if you get a Ram Hemi with the 8-speed, but a 4x4 and a towing rear end, then you're back at 14-15 mpg like the old Rams. I probably shouldn't have made the global statement about the Ram being better than the 5.3L, but I owned a 5.3L for the last 12 years and it's a dog of an engine from a power and efficiency standpoint (although mine was incredibly reliable). I had the 4-speed in mine, but it never did better than 16 or maybe 17 mpg on pure highway. My buddy had the 6-speed in his 5.3L with AFM and got basically the same mpg. I've heard with a better rear end you can get 18-19 mpg with the new 5.3L with AFM, but I still don't think it tops the best numbers that Ram's Hemi can put out.

Chevy's 6.2L is getting well over 20 on the highway with a non-towing rear end and 2WD, and I've heard you don't even have to baby it and slow down to get those numbers. I wish trucks with that motor were more affordable.

Yeah I had a buddy who had a 2007 with AFM and the 6-speed and his numbers for mpg weren't really any better. 2WD Z71 model, so I don't understand why his gas mileage still stunk.

I admit I have no experience with the newer ones, but I haven't heard of anyone getting 20+ on the highway like I do with the Ram/Hemi/8-speed with a 3.21 rear end. On the flip side, I have no personal experience with either of these motors in the last couple model years.

ETA: my 5.3L was a 2004 model. Only thing I ever had to do was clean the throttle body once. Bulletproof engine, but no power and drank the gas.

My fathers '11 z71 5.3 extended cab got the same or better mpgs as my 6 speed '13 2wd single cab ram. He can get 23+ highway in his '15 2wd 5.3. Just hand calculated his tank this morning and it was over 20 with mixed driving. The Ram is not going to beat the Chevy in the mpg category all things being equal. The hemi is a more powerful, higher compression motor that recommends using mid grade. Mine out performs a 5.3 hands down, but it's not gonna suck less gas doing it...even with a 8 speed.

My mom has a 2006 tahoe with 3.23 rear end its a great running vehicle. It gets around 20 on the hwy. Big thing is it is a 4 speed not a 6 or 8 like the new ones.

I'm 99% sure the only thing I have fixed pre 100K on my own vehicles at my own expense was a brake light on one of my dodges.