Ram 6.4 Hemi Fuel Economy

Anyone have a 3500 with this engine? Wonder what it gets just driving around empty, no trailer.

I think that is what the local oil delivery co. has. He really like it. Says it is better than what he had before. Was the 5.7 hemi before it ? I forget his actual MPG numbers.

I have one. 3500 4x4 bought as cab and chassis. installed a 9 ft flatbed, built in hitches. added Montezuma tool box. Mine is a standard cab. Scales at over 7000#. Handles a fully loaded 24 ft. goose neck stock trailer with no problem. Worst mileage was about 5.5, best, just over 12. Runs about 10 empty / no trailer. I'm OK with this, I once had a '460' Ford, auto trans 2wd. This one beats my old Ford. Doesn't sound very good, but I work this one hard and I didn't pay the 7K premium for a diesel.

Thanks! Finally someone who doesn't stretch the truth. I have a 6.2 Ford f250. 3.73 gears. Just a freckle better. But a little smaller.

My son has a 2500 2016 with that engine, he just got it about a month ago. I used it a couple of days ago helping him. I was pulling a dump trailer hauling loads of logs probably about 12,000 lbs loaded. Running 8 miles loaded and then 8 miles empty to get another load. City driving max of 45 miles per hour. The truck had 500 miles on it and computer was saying 9. something average miles per gallon. Don't know if that helps you any.

I had been researching gasser 3/4 ton trucks about a month ago. The Ram 2500 is coil spring and the 3500 istraditional leaf spring.

Anyway, I really like the prospects of that 6.4 hemi gasser but it is held back by a less than stellar tranny ratios. The ram ratio from 1st to 2nd gear is too large. (Maybe you can get the Aisian tranny in the 3500 which might help but the Aisian is not available in the 2500 with the gasser).

Sadly the Silverado 6.0 beats it in shoot outs from multiple sources. While the venerable 6.0 motor did get some tech improvements beginning in 2014 it is still way down on power compared to the 6.4 hemi. That said, the GM package outperforms the more powerful hemi when you add in the tranny and tranny programming as an entire package.

Real good videos on "The fast lane truck" and test results on "pickup truck * com" also support the the 6.0 chevy as the winner. It was awful watching the 6.4 ram trying to go up the ike gauntlet in 1st with the computer programming limiting it to 4200 rpm in 1st gear.

Granted these are extreme tests but the 6.4 should have cleaned the the 6.0 up the ike gauntlet but it did not due to its crappy tranny and worse yet crappy tranny/engine programming. Surprising the the GM 6.0 got the best unloaded and loaded mpg in multiple tests too.

It is all good reading and watching if you interested....

PS. I am not pushing GM either as I think the RAM would be unbeatable with a better tranny.

I have a Ford one ton dually that I bought new in 2011. It has the 6.7 liter diesel and I pull a big trailer, 24000 pound load, I get between 11 and 12 mpg when I am loaded and average about 13 with the unloaded trailer. When there is no trailer hooked on I get up to 18 mpg in the summer and always 15 or better. This is the best truck that I have ever owned and I have owned many different makes and models over the years. Happy farming.

Thanks for the replies. It is very helpful. We have two Ford diesels for the heavy work but I am looking for a personal passenger vehicle to replace my van. I would like to drive a truck and the new 1/2 tons are claiming 20 mpg. I just thought if I could get a 3/4 or 1 tom and only loose 3 or 4 MPG, it would be handy on the gooseneck once in awhile. Looks like I should stick with a 1/2 ton.

Yes for a daily driver no doubt the 1/2 ton is the way to go for MPG especially since you already have backup diesels for the heavy work. You might even one a look at the midsize Colorado as a daily driver. Some of the mpg that Colorado attained in some of those tests in both the gasser and diesel version were both incredible.

Oddly enough, the reason, I started looking @ 3/4 tons in the first place is my 2003 GMC 1500 5.3 with 4.10 rear end the MPG had fallen off by approximately 3 mpg from what it always got which was never great but it is one pulling son of a gun for a half ton truck and a small V8 (I work it extremely hard at 3/4 ton levels occasionally but not daily. It would not work at those 3/4 ton levels without that 4.10 rearend).

For the mileage drop off I was considering a modern 3/4 ton gasser for less pushing of the envelope.

Anyway all those detrimental claims you read about people eliminating the muffler, or putting the custom loud mufflers on their small block V8 gasser trucks for the so called cool sound are definitely true. Most experience a dramatic MPG drop for the worse when they do this whether they will admit it or not is another matter. I had not changed anything on my truck as it was still stock but my muffler was rusted were a heat shield was strapped on. Had a hole about the size of my fist in the muffler. Truck sounded real good without being obnoxiously loud so I was not gonna fix it....Until I noticed my MPG had dropped 2.5 to 3.0 and repeatable every tank.

Crawled under the truck zip screwed a scrap sheet metal patch over the hole in muffler and the mpg has returned to right were it always was (16 MPG'ish).

My mileage returning to acceptable and those outrageously high prices on new trucks made me decide that I will keep what a got for a bit longer.

Small blocks V8 gassers need some back pressure to run right. Bigger pipes and less muffler resistance is simply not always the answer for fuel economy especially and they can hurt power levels too.

2015 Ford 6.2, 3.73s, 11,000 miles, average 13.1mpg lifetime. It will go up almost 1 mpg if you unlock the front hubs. About half the time I am hauling or towing with it.

I don't understand how a reduction in back pressure could be causing a significant drop in fuel mileage. Not saying it can't happen just don't understand the linkage. Could it be the hole in the muffler allowed fresh air to mess with the O2 sensor, causing it to call for more fuel?

(quoted from post at 04:13:38 01/31/16) I don't understand how a reduction in back pressure could be causing a significant drop in fuel mileage. Not saying it can't happen just don't understand the linkage. Could it be the hole in the muffler allowed fresh air to mess with the O2 sensor, causing it to call for more fuel?

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The muffler is well behind both o2 sensors so I would not think it is that. That said, I do not know what the real theory is either. There are lots of stories on the internet about people paying big bucks for high dollar custom sweet sounding exhaust systems and then their mileage goes in the crapper. I certainly believe that now after experiencing it in an indirect way. (Thank god it did not cost me $700- $900 to learn this invaluable lesson like it does so many other people).

I can only speak of my truck's circumstances but 12.0 to 12.5 mpg highway empty unloaded had me strongly considering a modern 3/4 ton gasser (afterall my truck is 13 years old). My return of normal of 15.7 to 16.5 mph empty highway has me happy to keep what I got especially with new trucks in the neighborhood of $50K.