We Drive Ram 1500's Diesel in a Jeep

2013 Ram 1500 Rambox II
By G.R. Whale

Now that Ram has confirmed a diesel light-duty Ram, it’s just in time for us to sample Chrysler’s A630 VM Motori 3.0-liter diesel engine on the Jeep Grand Cherokee media drive. Yes, we know that the Grand Cherokee is not a pickup. However, we think it will give us a good baseline for what to expect when the EcoDiesel is dropped into the Ram.

We expect many systems to be similar in the Grand Cherokee and Ram, including the electrical architecture, the eight-speed automatic transmission and the engine choices. Jeep prices the diesel option at $4,500, and chances are it shouldn’t cost any more when dropped into a Ram.

A Grand Cherokee with the diesel option (the same versions that offer a Hemi) weighs from 5,065 to 5,374 pounds; the gas-engine Grand Cherokee weight ranges from 4,545 to 5,219 pounds. By comparison, the Ram 1500 base (with the V-6) weighs from 4,502 to 5,859 pounds, and the top GVWR of 6,800 pounds is the same as the Jeep 4WD. The maximum gross combined weight rating for the Jeep is 13,100 pounds where the Ram runs from 9,500 to 15,650 pounds, depending on its powertrain and gearing. Rams will use different transfer cases and slightly larger ring-and-pinion sets, and the Ram’s 17-inch tires and wheels are similar to the 18s on a diesel Jeep. The Ram and Jeep should use the same alternators.

Aerodynamics will be the bigger factor in making a comparison. Jeep’s quoted coefficient of drag value is 0.371, higher than the Ram’s 0.360, but we’re guessing a diesel Ram may not get all the high fuel economy tweaks. We don’t think that’s enough to overcome Ram’s larger front, so it makes sense to us that city mileage ratings will be similar but highway ratings will be slightly less than the Grand Cherokee. No doubt a lot will depend on gearings and tire choice.

The VM is a 60-degree under-square 3.0-liter engine with an iron block, aluminum heads, overhead cams and a compression ratio of 15.5:1. It uses a single water-cooled Garrett turbo in the back of the valley, solenoid common-rail Bosch injection (with up to three pilot and two post-injection events per cycle and 29,000 psi) and selective catalytic reduction. 

The gas tank has a a capless arrangement that wasn’t quite up to Jeep angles on the prototypes we drove; the tank can hold up to 24.6 gallon fuels, and the urea reservoir is sized to 10,000-mile refill intervals. The oil system has been developed for the steep angles one expects to tackle in a Jeep, and for cold-weather cabin performance Jeep has electric heaters in the air ducts.

Because the temperatures at the event were above freezing, we couldn’t test how long it would take to start the diesel in the cold. For us, at 53 degrees, the wait was no longer than the “ignition on” bulb-check function. The gravelly diesel growl is well muted, with injector tick quieter than some gasoline engine idles — BMW’s 2.0-liter I-4 comes to mind. If you’ve driven any recent 3.0-liter-range six-cylinder diesel, be it VW’s corporate unit, Mercedes’ 72-degree V or BMW’s inline arrangement, the sounds and numbers will be familiar to you.

Throttle response is average. Mash the accelerator from a full stop, and there’s a quiet step-off followed almost immediately by full power, and while it’s certainly not as fast as a Hemi, the diesel engine delivers an effortless midrange-rpm surge that will make passing just an excuse to exercise the turn signals. Jeep didn’t offer a zero-to-60-second time, but the Jeep feels competitive with the Germans, probably getting to 60 mph in the 7.0- to 7.3-second range.

Jeep hits that magic 30 number (EPA highway mpg rating) but only for the 20 percent of Grand Cherokees that are rear-wheel-drive; 4WD delivers 21/28 city/hwy ratings, very similar to comparably weighted competitors: VW Touareg (20/29), Porsche Cayenne (19/29), M-B ML350 Bluetec (20/28) and BMW X5 35d (19/26). Note that Jeep also claims 17/25 (17/24 4WD) with the 3.6-liter V-6 Pentastar and 14/22 (14/20 4WD) for the Hemi backed by an eight-speed automatic. That’s never more than 1 mpg different than the Ram V-6/eight-speed and only 1-2 mpg better than a Ram Hemi with the six-speed automatic.

VM Motori is a 50/50 joint venture between Fiat and General Motors but unless GM is sandbagging a well-concealed diesel program for the new Silverado or Sierra, Ram will be the first half-ton to market in the U.S. with a diesel engine. And if Nissan puts a baby Cummins in a Titan, our test title won’t be a misprint: Ram Diesel Versus Cummins Showdown.

2014 VM Motori 3.0L V-6 2 II

2014 Jeep Grand Cherokee II

2014 ZF 8-spd II



Can't wait to see one of these on the street and hear it.

Oooh yes a 30 mpg RAM!!!
Now beat that Ford and Gm! Like Lou said, ram is the direction everybody will follow. Great this will be my next Ram truck!!!
RAM the king of trucks!!!

I'm glad ram is coming out with a diesel, but I'm a little doubtful about the 30 mpg people keep throwing out. A 4x4 jeep with the diesel they say will be about 24 mpg combined (20 city/28 highway). So I'd say that the ram 4x4 will be about 23 mpg combined (they are saying it will get slightly worse mpg than the jeep). I average 16 mpg in a ram 4x4 now with a 5.7 so with the new 8 speed that will probably be closer to 17 mpg. With gas at 3.19 and diesel at 3.89 after 200,000 miles of driving you'd only save $3,800 on fuel with the diesel engine. The premium for the diesel engine will probably be at least $4,000 right? So basically I could never justify it on fuel savings if my numbers are right. Most people wouldn't do the math though and I bet they will sell quite a few of these. No doubt the ecoboost is way overrated as far as gas savings but they are still selling well. I think it's a no-brainer to get the 5.0 if you are going ford (better reliability and comparable power and fuel economy without the premium price). I think ram will do well with the diesel but highly doubt I would buy one. This is of course disregarding all of the other pros and cons of owning a diesel. I think a lot of people would buy them even if they only averaged 19 or 20 mpg.

50% of the profit goes to General Motors, wait until all the numbers are out on the 2014 Silverado and Sierra.

Is that $4500 upcharge to go from the Pentastar to the diesel or to go from the hemi to the diesel?

So essentially, it has the same towing capacity as the current 5.7L V8/6-spd, but yet gets about:
50% better city fuel economy
40% better highway fuel economy

At the current national average, diesel fuel is 9.74% more expensive than regular gasoline, and 5.42% more expensive than mid-grade (recommended 89 octane for the 5.7L).

So, lets say one does at least 10,000 city miles per year:

5.7L will cost $2697.86 (on regular gas)
3.0LTD will cost $1973.81

A yearly saving of $724.05

The DEF tank holds 8.5 gallons. Assuming you're buying it in 2.5 gallon jugs from Walmart or NAPA, you would end up spending $60 with tax. It also costs about $30 more for an oil change using Mopar oil.

That knocks it down to $634.05

The diesel is $2,800 more than the current 5.7L/6-spd. So it will take about 4 1/2 years for the diesel to pay for itself.

Lets say it takes 5 years to pay for itself. If you hang onto it for 10 years total, that could represent a potential savings of nearly $3200 over the life of the vehicle.

Obviously, that number is going to vary significantly from person to person and from location to location, but it does seem to suggest that the diesel could, potentially, be worth considering as an option over the 5.7L. However, if you don't do any towing, just by looking at the numbers, I doubt it would be worth it over the base 3.6L V6 gas engine.

@ Paul

I will be real interested to see the mileage reported once PUTC tests the ecodiesel vs hemi vs ecoboost side by side by side to compare towing mileage. The diesel may pay off very quickly for people who do a fair amount of pulling.

@beebe and @phillyguy

The $4500 number is the option price over the 3.6L Pentastar V6.

In the Jeep, the option price for the 5.7L is $1,695.

That makes the diesel a $2805 option over the 5.7L.

If the Ram can come out with a 6 speed manual that would be a great bonus as it would knock another $1000+ of the price.

But Ram only has 10 000 diesel engines to use, so many will probably be high end trucks to make a bigger profit on. If that occurs it will be a pity as working trucks would benefit more.

The acceleration times seem a little optimistic though, at best I thought maybe 9sec to 60mph for a 2wd Ram. The same goes for the mpg's, a little high. I would think they would be on par with the Grand Cherokee.

I don't know if the 8 speed will have as big an impact on the fuel economy as it does with the petrol engine.

Highway driving a top gear is top gear. Like where I live the roads are very open and once in top you leave it there until you need fuel again. Even around town the diesel is a tractable engine.

I can't see Nissan using the 2.8 Cummins now, that was being looked at when Nissan was considering pairing up with Ram.

The V6 Renault diesel would be my guess as it would be extremely competitive against the Ram. Its also an engine Nissan already is using in our Navara (Frontier). Apparently it goes like a rocket.

In some of the reviews they state you would think it was a petrol V8. Its willingness to rev is commented on.

As for Chev/GM the only engine possible is the 2.8 diesel fitted to the Colorado. If that engine is used in the Colorado then it wouldn't work that easily from a marketing perspective. Some of our base model Colorado's come with a 2.5 diesel.

And if Ford does decide to place a diesel in the F-150 it has two choices. The Lion 3 litre V6 diesel (expensive) or the 3.2 Duratorque (global Ranger/Transit). The 5 cylinder 3.2 would in my mind would be the choice, due to the costs.


That's what I'm curious about as well.

The guy I go snowmobiling with has a crew-cab 5.7L 1/2 ton and he is lucky to get double digit fuel economy towing his three place snowmobile trailer. My old diesel Suburban, on the other hand, does about 15 pulling a heavier 4-place trailer. If this engine does any better than my old girl, that could mean almost double the towing fuel economy.

Since I'm in the market for a new truck, I would definitely take that into consideration.

After reading what I wrote and it does unfold that way.

Ford will probably end up with the cheapest diesel pickup.

Chev will only have a diesel Colorado.

I didn't mention the Tundra, but it would be silly for them to compete with the Big 3 and Nissan.

If they drop the 4.5 V8 diesel from the Landcruiser into the Tundra, it could be a competitive choice rather than buying an HD. The pricing would also be more compeitive against an HD diesel.

I know over the past year I have been at times "screamed" off of this site over my diesel comments.

But the reality is like I've been saying, these 3 litre class diesels are quite good.

Towing and off roading they will return fantastic fuel economy.

Most of you guys have had limited exposure to these engines.

My vehicle which weighs about 4 700lbs driving at 85mph can deliver over 20mpg. (before anyone complains, the speed limit is about 85mph were I live). If I sit on 60mph the figure goes above 30mpg.

That's with a 3.2 Duratorque or as it will be called in the US a baby Powerstroke.

The 3.2L I5 diesel in the F150 would definitely make a lot of sense if Ford was looking for a diesel to use. It could share production costs between the F150, full size Transit, and T6 Ranger. Sounds like a great way to keep the option price low.

It would be interesting to see how it competes with the 3.5L Ecoboost. That engine carries a ~$2400 option price over the base 3.7L, yet it still gets roughly V8 fuel economy when towing. If the diesel does significantly better, and only costs ~$1500 more than the Ecoboost, I think it would make a lot of sense for some people.

@Paul 810
Looking at the additional costs for the VM diesel in the Ram I would think there is a little profiteering from Ram.

The 5.7 and VM diesel costs the same in Australia. The 5.7 doesn't come with an 8 speed in the price and that would amount to over $1 000.

That's why I think a 6 speed manual gearbox would be a good option, it would knock down the price.

Another manufacturer has to come out with a diesel 1/2 ton pickup to keep the prices realistic. Competition is what is needed.

The only problem with that is, at least stateside, less than 1% of new car buyers opt for a manual transmission. Other than a few enthusiasts buying them, it's pretty much a dying art here. Most young kids don't care to learn and the old guys that know how just don't want to shift themselves anymore I guess.

With such a low take rate I doubt selling it with a manual here would save any money. In fact, it wouldn't surprise me if they charge more for it.

(Speaking of which, it's always fun to put someone in one of my Brockways with 5+4 duplex transmissions. They look at the two sticks and the extra pedal, and then instantly give up.)

The only way to 'justify' buying one would be if you towed daily and put many miles on your truck. If you can rack up enough miles the numbers could eventually work out. Otherwise it offers another option for guys wanting something different, and I think that's where the sales will go. An engine not as powerful or quick as the HEMI, but with more grunt than the low end engines. But if there will only be 10,000 available, you'll be paying top dollar for the engine as I don't see them offering many in lower trim levels. As a comparison, Ford sells 10,000 EcoBoosts in 20 days.

why is Ram not a dodge anymore im confused is Fiat still mad Dodge trucks kicked there butt in ww2 ??

Don't forget to include resale value when doing a cost analysis. Diesels typically hold a higher resale value.

@Big Al, I think Ford should offer the 3.2 I-5 as a base diesel (skipping the 3.0 V6 - unless they can use the Lion with competitive pricing) with an optional 4.4L V8 diesel in the F-150 and Transit. The 4.4 V8 should be the base diesel in the Super Duty with the optional 6.7.

I would be a lot more interested in the Colorado diesel.I have no need for a full size PU.

@Paul810- thank you for using actual numbers. Since your calc is based on only 10k, its actually pretty favorable. That leaves you ahead month to month, while paying for the truck. While it isn't quite as fast as the Hemi, it will drive great, pull awesome and give you better range.
As long as they don't limit availability, this should be great.
As to transmissions, a manual trans just wont happen. The 8speed should make a bigger difference on the diesel than on the gassers, since it will be able to hold the highest gears more of the time, due to the torque available below 2000rpm.

@Big Al: If they made it a manual trans, why have just 6 speeds?

The current Jeep 6 speed used in Wranglers (I have no idea of it's torque input rating) has like a .84 top gear. That doesn't even compare to the 8 speeds .67, and in a diesel that runs a lower rpm, why would you not want it? It would be somewhat behind if it had only 6 gears.

I can see them making axles with a 3.0 range to start with, instead of the 3.21s that are currently lowest numerically. Since they will be making differant ones anyway.

I think there would be a place for people that could get a manual trans, as everything else half ton is auto, and Ram offers the only manual in the 2500 and 3500s.

Can we delete all the ram glory posts? I'm a fan of Ram trucks and don't plan to purchase anything else, but it makes me cringe whenever I see guts! Glory! Ram! Because it just looks idiotic. Again I love Ram trucks but I want to be taken seriously.


The one assumption you are building into your consideration is that gasoline will remain less expensive than diesel into the future. I have no idea if this is true or not since I don't know why diesel costs more now. But I do remember a time around 2000 when diesel was always less expensive per gallon than gasoline. If that price scheme were to return a motor like this VM 3.0 could be a *huge* cost saver.

With that, does anyone know why diesel costs more than regular gasoline now? Was it the switch from LSD to ULSD? Any thoughts on if they'll switch back?

With this diesel get the twin-torsional isolator on the torque converter?
I would be nice to have a fully locked up torque converter clutch at 1,000rpm (and at full load)


I believe that big oil wants to see 5 bux a gallon for reg gas and I think they will get there without any govt interference like in the old days (regulation).Where will that put diesel,which used to be cheaper because it is a by product of the gasoline making process? I'm not sure a horse wouldn't be a better deal,lol.

I cna drive a manual and actually prefer it, however there are none to be had in half tons anymore, addtionaly towards the end you could not get them in the higher trim levels. I learned how to drive on My moms diesel jetta with a 5 speed manual when i had my learners permit, im the oldest of 6 kids and the only one who drives an automatic (2010 SVT Raptor) we have the family 99 suburban (auto) at the vacation home eveyone else drive manual for their DDs Dads drives a 2011 5.0 mustang , mom drives 2012 Passat TDI , little bro has 2001 nssan pathfinder 4x4 and 2012 jetta sportwagen TDI, Other Borther has 98 ford exploer 4x4, sister drives 2012 Chevy Cruz, littlest brother drives my dads old 93 Taurus SHO, littlest sister is to young to drive. Its funny my littlest brother drove the raptor and went to put the clutch in when driving with his size 14 feet and hit the brake pedal since it extends to were a clutch pedal would be, needles to say we stopped fast.

phillyguy, This is straight from the Energy Administration Information website, and I don't see the price getting any closer than it already is:
On-highway diesel fuel prices have been higher than regular gasoline prices almost continuously since September 2004, a break from the historical pattern of diesel fuel prices usually being lower than gasoline prices except in cold winters when demand for heating oil pushed diesel fuel prices higher. The main reasons why diesel fuel prices have been higher than gasoline prices in recent years are:

High worldwide demand for diesel fuel and other distillate fuel oils, especially in Europe, China, India, and the United States, and a tight global refining capacity available to meet demand during the period of high economic growth from 2002 to mid-2008.
The transition to less polluting, lower-sulfur diesel fuels in the United States affected diesel fuel production and distribution costs.
The Federal excise tax for on-highway diesel fuel of 24.4 cents/gallon is 6 cents per gallon higher the gasoline tax.

@Beebe: where in the world are you getting gas that cheap? 3.19?? This weekend I was up in Springfield Mo, which is somewhat known for having lower average fuel cost. I seen alot of 3.57 a gallon, but 3.50 a gallon @ Sams Club was the best we could do.

We woulda taken my ladies little 1.8L Nissan Sentra had we not been buying kayaks.

I sincerely hope that with production volume the VM diesel comes down in price as an option. As pointed out be a few people the better comparison isn't the 3.6 V6 but the 5.7 V8 which is only a $2800 increase. I was hoping for it to be closer to a $1500-2000 increase though.

Should be a great motor for those who put a lot of miles on their truck or do a modest level of towing or live in higher elevations.

I'll seriously consider this truck but the payload must increase for my personal needs. Since GM is likely to have payload options up to and over 2000 lbs they may be my best bet and I hope they have a license to sell this motor too!

There was a good article written last fall, describing a pretty extensive cost analysis including 23 diesel vehicles. It assumed 15,000 annual miles and 5 years of ownership. 7 diesel trucks were in the study and only one of them made the cut. You can read about it here:

$4500 buys a lot of gas...

You buy a diesel because you need the pulling power, not to save money.

I believe that VM Motori is no longer a JV with GM, Fiat bought 100% some time back....

I do see that everyone is forgetting the flip side of the math equation....the resale value.

This will likely tip any costs in favor of the diesel. We obviously have no directly related data since this is the firsttime since about 1994 that a 1/2 ton will have a diesel but if we use the heavy duties and even some other autos the diesel ALWAYS has the greater resale value and the difference typcaily shows that the engine option costs a buyer around 20% or so over 5 years of ownership. That is a very low depreciation amount.

@ JST: Do you have a link to that? I can't find anything that says that.Everything I have found still lists GM as a half owner.


Thanks, that was interesting. Too bad really. It would be great for half tons to start getting smaller displacement diesels and then have diesel fuel simultaneously drop in price. Oh well.

What additional maintenance is called for in the driver's manual for the jeep with the 3.0 VM? Is there a lot of extra maintenance over its gasoline alternative or is it not such a big deal?

At a 2800 premium, I think the diesel engine makes a good argument for being an alternative for the Hemi.

But a 4500 premium over the V6, is going to be hard to swallow.

From what I've read, GM owns half of VM Motori but the 3.0L was a 100% Fiat project. I think the walls separate the two owners.

You wrote " The VM is a 60-degree under-square 3.0-liter engine with an iron block,"

Well t´s a CGI, Compacted Graphite Iron block. The new block material.

I am glad Ram stepped up to put a diesel in the 1/2 ton, about time. This is good news , if the diesel 1/2 ton sells well then GM and Ford will release their 1/2 ton diesels.
I will be watching to see how many buy a diesel 1/2 ton,with the cost of diesel fuel being more than gas, the initial cost of diesel truck being thousands of $$$ more than a gas truck, it is a tough call.

@phillyguy, great analysis -thanks for taking the time to run the numbers. Remember though, if history is any indication you'll get your initial investment for the diesel, and then some, back at resale.

(e.g., I paid $28k for my 2003 Ram 2500 CTD new and sold it for $18.5k in 2011. The upcharge from a Hemi was $4.5k. Similar 2500 Hemis were selling for $11k. So I made my diesel investment back + a little).

@TRX4 Tom
The extra cost of an 8 speed I don't think is necessary for a diesel yet. Because of the torque spread of a diesel in comparison to a gas engines less gears are required. I'm not saying not to have an 8 speed option.

The gain will not be as big as the fuel savings in a gasoline engine. It's just not a necessity yet.

Gas in fact should cost more than it does but parts of gasoline is subsidised. The actual amount would be hard to determine. Ethanol in your gas is grown by subsidised farmers.

I know in Brazil which has a substantial Ethanol industry the US just paid (if I remember correctly) $2.30 a gallon (before loading), but it still needed to be handled, transported, stored etc. It doesn't leave much profit in the end.

In the US's crude oil cut 25% goes to domestic and commercial heating. Heating oil is a distillate also. But the US is wasting money subsidising and giving handouts to CNG HDs. Doesn't make much sense. Why not use the natural gas for heating.

There isn't a shortage of distillates, you actually get a higher percentage of distillates per barrel of oil than you can obtain gasoline.

@TRX4 Tom
There is another apect of gearing I'll teach you about.

First you have torqe and load. Speed is also significant.

So you have torque, load and speed.

Now you quote all gasoline engine ratios from brochures, but now work out diesel ratios. You must consider how th torque of an engine impacts speed.

TRX4 Tom
What I'm asking also is the difference in fuel expenditure between a diesel and gas a any given torque load.

There is alot to consider when considering gearing.

I'm not say an 8 speed will not improve economy, but how much? Is it worth the expense?

An 8 speed is a great marketing tool for Fiat/Ram.

Yes excuse the pun it will be a "snowball" effect. I know the manufacturers are looking at introducing diesel engines in quite a few vehicles in the US. The Diesels have a lot of their start up costs written off as they are already in production outside the US.

@Big Al: You will teach me? There is a funny thought!

Hey, don't you work on planes? So because you sit there and wait to see what safety of flight comes up, that makes you some sort of expert?

You don't want an 8 speed with a diesel? That must mean you are AGAINST CHANGE.

I am curious Al, just what you suggest they put behind a diesel? The current 6 speed? The one which has a big spread between 1st and second, then has two gears real close, 1.67 and 1.5, and then also has the two overdrives real close, .75 and .67.

Sure they could redevelope a 6 speed. Spend a bunch doing it. They also have the 6 speed that 2500 gassers run, much better gear spacing.

But it just sounds funny that you would say an 8 speed wouldn't be worth it.

Now if you are actually talking six speed manuals they have, maybe if you actually looked at the ratios instead of just being yourself, sence you spew out a bunch of talk.

@TRX4 Tom
Gearing is gearing, you said you understand gearing. To drive generators, props and all ancillary equipment on an aircraft uses the same maths and physics.

The laws of physics aren't any differenet for a Fiat/Ram than a Ford or for that matter a Boeing or GE jet engine. So you are arguing about water being wet or dry.

Tom, a diesel has different characteristics than a gas engine.

You haven't to much data from a brochure regarding the 3 litre VM diesel? Listen and learn. Look at the concepts I'm putting forward to you.

Also, your comment was a deflection or put down. That re-enforces that you don't know.

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