Ram 3500 DRW 6.4L Hemi "Game Changer"

[ib516]

Truck Camper Magazine article and review HERE

18.2 mpg empty and 12.8 mpg with a 4700# slide in camper on board with 3.73s. That's with a dually!

The truck has 5800# plus payload and would have been over 6500# if they had opted for the 4.10 ratio. Apparently, the GVWR changes with gear ratio. 3.73 is 13,300# and 4.10 trucks are 14,000#.

[spoon059]

Ron3rd wrote:
Correction: Our Tundras have 401 ft lbs of torque. 🙂

Sorry, my mistake... 😃

In Florida last year we camped next to an older couple in a Winnebago Vista or View or something like that. It was a large class B, almost like a class C without the front overhang. I was talking to the guy about it, it had a Mercedes diesel and he said he got about 24 mpg towing all around the country. I was stunned when he said that.

I looked at the floorplans at the time and none were suitable for my family needs... but man its hard to beat going cross country at 24 mpgs! My wife's Camry gets about that, but I sure wouldn't want to sleep, eat and go to the bathroom in that thing!!!

[Ron3rd]

spoon059 wrote:

Cummins12V98 wrote:

Both figure $4.00 per gallon.

Except gas is about $3.30 gallon here, diesel is $3.89. Obviously the vehicle with the best mpg will be cheaper at the same price of fuel.

Reality is that diesel is more expensive. In my area diesel is roughly 20% more expensive that gas. If you are simply using "COST" as a reason to buy a diesel, you need to make sure you are getting 20% better fuel economy with the gasser. Even then, you are simply breaking even. When you figure higher cost to purchase and maintain, you need an even bigger delta to make financial sense.

I don't know how many times we can keep having this argument and keep having the same old tired clichés thrown out.

If you need a diesel due to higher weights or more time spent at higher elevation, get it. If you want a diesel because it makes you feel better, get it. If you are buying a diesel because it makes sense financially... double check your numbers.

If you don't need a diesel because you are towing at around 12,000 lbs or less, the 6.4 looks like a great engine. If you don't have an additional $8 grand to drop on a diesel over the 6.4 gasser, the 6.4 looks great. If you aren't constantly up in the mountains and worried about less oxygen and less engine output, the 6.4 looks great. If you don't feel the need to justify yourself to the diesel crowd, the 6.4 looks great. If you are satisfied with your love life, the 6.4 looks great. If you aren't towing exclusively with your vehicle and still use it as a daily driver but want a ridiculous amount of power to tow, the 6.4 looks great.

Lets not forget that 10 years ago in 2004, the MIGHTY DIESELS had the following numbers...

6.6 Duramax had 300 HP and 520 lbs/ft torque
5.8 Cummins had 325 HP and 600 lbs/ft torque
6.0 Navistar had 325 HP and 560 lbs/ft torque.

The 6.4 has 410 HP and 429 lbs/ft torque. This gas engine blows away those diesels. Technology is changing boys and girls. You don't need a diesel to pull the weights that you did even 10 short years ago. Hell... my Tundra engine has 380 HP and 400 lbs/ft torque.

Bottom line, buy what you want and keep your nose outta what your neighbor buys. Why do some people care so much about what other people drive? You want me to drive a Big 3 diesel truck... donate some money or keep your opinion to yourself. You don't like the 6.4 gas engine, don't buy it. You feel the need to compensate for other "shortcomings"... do what you have to do.

Correction: Our Tundras have 401 ft lbs of torque. 🙂

[RoyJ]

wintersun wrote:
People always seem to assume that with a heavy truck the 3.73 gears are going to provide better fuel economy than 4.10 gears in real world use when there is no reason to believe this is true.

I always emphasize the importance of transmission internal ratios when comparing rear end ratios.

The 66/68RE has a relatively tall 1st gear, and benefit heavily from a deep rear end such as 4.10. The 8 spd ZF on the other hand, has a super deep 1st gear (4.7:1), and can easily get away with a 3.21 rear end, all else being equal.

The B Class Roadtreker motorhomes with their Mercedes 5-cylinder diesel engines get 25 to 28 MPG in actual use with them fully loaded and passengers on board. That is more than double the fuel economy of the Ram with the camper.

Somewhat apples to oranges though, as the truck is many times more capable than the camper. An empty 1st gen Sprinter was rated to tow 5000lbs, the conversion would be lucky to pull 2000 lbs with 154 hp.

The 410 hp Hemi can run circles around it pulling a trailer 3 times that weight while carrying the camper...

[MM49]

ib516 wrote:

wintersun wrote:
People always seem to assume that with a heavy truck the 3.73 gears are going to provide better fuel economy than 4.10 gears in real world use when there is no reason to believe this is true. The higher gears make a difference with the EPA test that is done indoors with the truck not moving and this helps the fleet mileage overall. This is not the same as dealing with gravity and air drag and tire scrubbing in the real world.

I got 17 MPG on average with a 1998 Tahoe SUV with the largest V-8 sold at the time and that was with 4.10 gears and a 4-speed automatic transmission where 4th was a 1:1 gear with no overdrive. Now we have 6 and 8 speed transmissions that have 2 or more overdrive gears to compensate for the lower gears in the differentials.

The Ram gas engine like the new engines from GM have the very old approach (used in the 1980's with the Cadillac) of shutting off gas to some of the cylinders. Trucks benefit from lighter weight and more gears and in some cases with better motor oil that is a lighter "weight" to gain fuel economy. Even so this is a trivial gain in terms of the total cost of ownership.

The B Class Roadtreker motorhomes with their Mercedes 5-cylinder diesel engines get 25 to 28 MPG in actual use with them fully loaded and passengers on board. That is more than double the fuel economy of the Ram with the camper.

All GM 4 speed autos in 1998 were 1:1 in 3rd and 4th was overdrive (0.69:1). It would have been a 4L60E trans in that Tahoe BTW.

25-28 mpg? Really? Most reports I read say 16-21 mpg....
What kind of hp/tq does the Mercedes 5 cyl have? More than or equal to 410hp/429tq? If not, then it is likely it can get better mpg, but it has less power. Depends what you want.

A Prius with a tent in the cargo hatch would get ever better mpg than a Mercedes class B MH, but it too has less power.

Every single topic is wrong in the attached note.
MM49

[45Ricochet]

Sport45 wrote:

45Ricochet wrote:

ib516 wrote:
If you want to compare total cost of ownership, you should know that the 6.4L Hemi in the trucks requires the same full synthetic 0w40 oil that the SRT cars require. Oil changes at the dealer are around $100. It takes 7 quarts like someone mentioned earlier. It only needs 87 octane, not 89 like the 5.7L though in case someone was wondering.

The oil isn't much of a big deal to me since I'd likely use synthetic in the winter anyway as it gets dang cold here (-40*).

Thats Celsius right?

-40 is -40 in °F or °C, as that's where the scales cross. But then maybe it was a trick question. 🙂

Dang you got me on that one, your right about the -40 :B minus anything is, well cold.

[ib516]

wintersun wrote:
People always seem to assume that with a heavy truck the 3.73 gears are going to provide better fuel economy than 4.10 gears in real world use when there is no reason to believe this is true. The higher gears make a difference with the EPA test that is done indoors with the truck not moving and this helps the fleet mileage overall. This is not the same as dealing with gravity and air drag and tire scrubbing in the real world.

I got 17 MPG on average with a 1998 Tahoe SUV with the largest V-8 sold at the time and that was with 4.10 gears and a 4-speed automatic transmission where 4th was a 1:1 gear with no overdrive. Now we have 6 and 8 speed transmissions that have 2 or more overdrive gears to compensate for the lower gears in the differentials.

The Ram gas engine like the new engines from GM have the very old approach (used in the 1980's with the Cadillac) of shutting off gas to some of the cylinders. Trucks benefit from lighter weight and more gears and in some cases with better motor oil that is a lighter "weight" to gain fuel economy. Even so this is a trivial gain in terms of the total cost of ownership.

The B Class Roadtreker motorhomes with their Mercedes 5-cylinder diesel engines get 25 to 28 MPG in actual use with them fully loaded and passengers on board. That is more than double the fuel economy of the Ram with the camper.

All GM 4 speed autos in 1998 were 1:1 in 3rd and 4th was overdrive (0.69:1). It would have been a 4L60E trans in that Tahoe BTW.

25-28 mpg? Really? Most reports I read say 16-21 mpg....
What kind of hp/tq does the Mercedes 5 cyl have? More than or equal to 410hp/429tq? If not, then it is likely it can get better mpg, but it has less power. Depends what you want.

A Prius with a tent in the cargo hatch would get ever better mpg than a Mercedes class B MH, but it too has less power.

[wintersun]

People always seem to assume that with a heavy truck the 3.73 gears are going to provide better fuel economy than 4.10 gears in real world use when there is no reason to believe this is true. The higher gears make a difference with the EPA test that is done indoors with the truck not moving and this helps the fleet mileage overall. This is not the same as dealing with gravity and air drag and tire scrubbing in the real world.

I got 17 MPG on average with a 1998 Tahoe SUV with the largest V-8 sold at the time and that was with 4.10 gears and a 4-speed automatic transmission where 4th was a 1:1 gear with no overdrive. Now we have 6 and 8 speed transmissions that have 2 or more overdrive gears to compensate for the lower gears in the differentials.

The Ram gas engine like the new engines from GM have the very old approach (used in the 1980's with the Cadillac) of shutting off gas to some of the cylinders. Trucks benefit from lighter weight and more gears and in some cases with better motor oil that is a lighter "weight" to gain fuel economy. Even so this is a trivial gain in terms of the total cost of ownership.

The B Class Roadtreker motorhomes with their Mercedes 5-cylinder diesel engines get 25 to 28 MPG in actual use with them fully loaded and passengers on board. That is more than double the fuel economy of the Ram with the camper.

[Cummins12V98]

goducks10 wrote:

Cummins12V98 wrote:
goducks10

You should shop genosgarage.com

Mopar NanoNet 4 micron filter for all 2010-2014 Cummins $50.95!

If you are buying from the Dealer I would make sure the oil filter is the Stratapore. They are all made by FleetGuard Cummins filtration Company.

I've seen the Geno site. Prices are pretty good. I get the Mopar285 oil and Mopar609 fuel filter. It's the OEM filters. I figure if it's good enough for OEM then it's good enough for me. The 609 is a dual stage Stratapore.

Sometimes OEM has two grades of filters.

All filters on the Cummins engine are made by Fleetguard and painted with MOPAR labeling.

Geno's has MOPAR and Fleetguard side by side and sometimes the MOPAR is less $.

BTW the NanoNet fuel filter is 4 Micron and really should be used.

Nice there is another option to buy OEM for the Mighty Cummins at better pricing.

[Sport45]

45Ricochet wrote:

ib516 wrote:
If you want to compare total cost of ownership, you should know that the 6.4L Hemi in the trucks requires the same full synthetic 0w40 oil that the SRT cars require. Oil changes at the dealer are around $100. It takes 7 quarts like someone mentioned earlier. It only needs 87 octane, not 89 like the 5.7L though in case someone was wondering.

The oil isn't much of a big deal to me since I'd likely use synthetic in the winter anyway as it gets dang cold here (-40*).

Thats Celsius right?

-40 is -40 in °F or °C, as that's where the scales cross. But then maybe it was a trick question. 🙂

[rhagfo]

45Ricochet wrote:

ib516 wrote:
If you want to compare total cost of ownership, you should know that the 6.4L Hemi in the trucks requires the same full synthetic 0w40 oil that the SRT cars require. Oil changes at the dealer are around $100. It takes 7 quarts like someone mentioned earlier. It only needs 87 octane, not 89 like the 5.7L though in case someone was wondering.

The oil isn't much of a big deal to me since I'd likely use synthetic in the winter anyway as it gets dang cold here (-40*).

Thats Celsius right?
Clicky
I'll just chime in about cost of diesel maintenance. There is none with certain engines. Others are well, quite expensive.

45Ricochet, that isn't 100% true, but I will say 12 qt of oil every 10,000 miles isn't bad, I can get my Fleetguard oil and fuel filter from the local Cummins dealer for $12 and $18, but other than that just keeps on running.
I need to update signature as I just rolled 275,000 miles, headed back from the Moon now!

[45Ricochet]

ib516 wrote:
If you want to compare total cost of ownership, you should know that the 6.4L Hemi in the trucks requires the same full synthetic 0w40 oil that the SRT cars require. Oil changes at the dealer are around $100. It takes 7 quarts like someone mentioned earlier. It only needs 87 octane, not 89 like the 5.7L though in case someone was wondering.

The oil isn't much of a big deal to me since I'd likely use synthetic in the winter anyway as it gets dang cold here (-40*).

Thats Celsius right?
Clicky
I'll just chime in about cost of diesel maintenance. There is none with certain engines. Others are well, quite expensive.

[ib516]

If you want to compare total cost of ownership, you should know that the 6.4L Hemi in the trucks requires the same full synthetic 0w40 oil that the SRT cars require. Oil changes at the dealer are around $100. It takes 7 quarts like someone mentioned earlier. It only needs 87 octane, not 89 like the 5.7L though in case someone was wondering.

The oil isn't much of a big deal to me since I'd likely use synthetic in the winter anyway as it gets dang cold here (-40*).

[goducks10]

Cummins12V98 wrote:
goducks10

You should shop genosgarage.com

Mopar NanoNet 4 micron filter for all 2010-2014 Cummins $50.95!

If you are buying from the Dealer I would make sure the oil filter is the Stratapore. They are all made by FleetGuard Cummins filtration Company.

I've seen the Geno site. Prices are pretty good. I get the Mopar285 oil and Mopar609 fuel filter. It's the OEM filters. I figure if it's good enough for OEM then it's good enough for me. The 609 is a dual stage Stratapore.

[IdaD]

It's been helpful reading through this thread. I think if you look at the total cost of ownership, it's pretty clear that the difference between the Hemi and Cummins over the course of 10 or 15 years is probably immaterial. You'll spend $6k more up front for the Cummins but it'll be worth more when you go to sell it, so you'll recoup at least some of that.

So I guess it really does just boil down to which one you prefer.