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Unread 08-16-2013, 06:31 AM   #16
Kev M
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Quote:
Originally Posted by hemispin View Post
My calculations are using an 18 mpg average for the Hemi, 19 mpg for the V6, 24 mpg for the diesel, and an average of 15,000 miles per year.

<snip>

Let me know if this helps you out, or if you would like me to try a different calculation.
I'm a little skeptical of your choices for average fuel economy

2014's 4x4s are rated as

V6 - 17 / 24
V8 - 14 / 20
Diesel - 22 / 30

So your test assumes:

An average of 4 mpg higher on the Hemi than city/ 2 mpg less than highway

An average of 2 mpg higher on the V6 than city / 5 mpg less than highway

An average of 2 mpg higher than city rating / 6 mpg less than highway.

I would claim your numbers show a clear bias towards the Hemi.

I know that on our 2012 V6 Limited 4x4 (rated at 16 / 23) we tend to get 18-20 on mixed average (wife-me) and 24-26 highway (wife-me).
So I'd like to see you run the numbers at a less biased average/mean (or closer to what I think I could expect from my own experience).

How about the results at dead center of ratings

V6 - 20.5 mpg
V8 - 17 mpg
Diesel - 26 mpg

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Unread 08-16-2013, 06:54 AM   #17
nyrhockey23
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Quote:
Originally Posted by Kev M View Post
I'm a little skeptical of your choices for average fuel economy

2014's 4x4s are rated as

V6 - 17 / 24
V8 - 14 / 20
Diesel - 22 / 30

So your test assumes:

An average of 4 mpg higher on the Hemi than city/ 2 mpg less than highway

An average of 2 mpg higher on the V6 than city / 5 mpg less than highway

An average of 2 mpg higher than city rating / 6 mpg less than highway.

I would claim your numbers show a clear bias towards the Hemi.

I know that on our 2012 V6 Limited 4x4 (rated at 16 / 23) we tend to get 18-20 on mixed average (wife-me) and 24-26 highway (wife-me).
So I'd like to see you run the numbers at a less biased average/mean (or closer to what I think I could expect from my own experience).

How about the results at dead center of ratings

V6 - 20.5 mpg
V8 - 17 mpg
Diesel - 26 mpg
His screename isn't Hemi"spin" for a reason, ya know. But at least he didn't use 28mpg for the Hemi like kickrocks likes to mention in every thread he can get it in.

If we use the Hemi as the baseline, at 50/50 driving (city/hwy) the V6 should get +3.5mpg and the CRD +5.5mpg improvement. @ 75/25 (city/hwy) the V6 should get +3.25mpg and CRD +5.25mpg over the Hemi and @ 25/75 (city/hwy) the V6 should get +3.75mpg and CRD +5.75mpg
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Unread 08-16-2013, 07:12 AM   #18
hemispin
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Quote:
Originally Posted by Kev M View Post
I would claim your numbers show a clear bias towards the Hemi.
Perhaps you could say that. However, I'm getting a real world average of 19 mpg with my hemi. So I'm getting better mileage than I anticipated.

Quote:
Originally Posted by Kev M View Post
How about the results at dead center of ratings.

V6 - 20.5 mpg
V8 - 17 mpg
Diesel - 26 mpg
Sure, why not:

Break even point considering you purchase the "advanced tech package" on the gas engine options:

V6 = 11.3 years and about 169.5k miles.
V8 = 1.89 years and about 28.4k miles.

Break even point considering you DO NOT purchase the "advanced tech package" on the gas engine options, yet you have to buy it with the diesel:

V6 = 15.8 years and about 237k miles.
V8 = 3.77 years and about 56k miles.
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Unread 08-16-2013, 07:31 AM   #19
Kev M
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Quote:
Originally Posted by hemispin View Post
Perhaps you could say that. However, I'm getting a real world average of 19 mpg with my hemi. So I'm getting better mileage than I anticipated.
Well, my point is so are we on our V6, so there's no reason to assume either you or I wouldn't also get more than city rating from a Diesel right?

I suspect that has something to do with where we live, driving habits, how we use the Jeeps etc.

So a realistic comparison for US should reflect that across the board. No?


Quote:
Originally Posted by hemispin View Post
Sure, why not:

Break even point considering you purchase the "advanced tech package" on the gas engine options:

V6 = 11.3 years and about 169.5k miles.
V8 = 1.89 years and about 28.4k miles.
Ah, we're package/feature whores anyway, and again I prefer to keep the comparison as apples to apples.

That shows me a clear advantage to the Diesel over the Hemi FOR US, and a take-it-or-leave-it on the Diesel vs. the V6 (which is kinda nice since I don't really have a reason to get rid of our 12' yet). But it certainly tells me I could justify a diesel for our usage.

Thanks much.
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Unread 08-16-2013, 07:33 AM   #20
Dave2002ti
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Dont assume

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Originally Posted by loveracing1988 View Post
$165 for something I can get at Walmart for $8? Sounds like a steal!
Some automakers make replenishment of the Urea a dealer trip since the computer must be reset. We dont know with Fiat. You just cant dump in the fluid from the parts store since the vehicle goes into limp home mode unless the computer is reset.

JP magazine had an article back a few issues ago about diesels and diesel conversions and payback. Interesting article. You might want to read their formula.

Reason a gallon of regular cost what it does right now is a direct result of our screwed up foreign and energy policies. Right now a barrel of oil is being priced with turmoil in Egypt playing a big part. A barrel of oil should be selling for $85 or less. This is not a supply and demand issue. A rational energy policy in the US would also mean OPEC couldnt blackmail us any more and Putin and his cronies couldn't play games with Eastern Europeans.
Drilling off our coasts and telling Republican govs in Fl, NC, SC and VA to pound sand would be a good start. Environmental damage would be minimal and I am a body surfer for over 45 years.

Again diesel is subsidized by the EU and UK and I also believe Aussie and NZ govts.

I keep a vehicle approx 6 years before I sell. I used to keep them longer but as they became more complex ie more computers etc I no longer keep vehicles for 10 to 12 years. I dont care about emissions or clean air since billions of Chinese mean anything I do is worthless.

Just wait until the Obama administration drives up the price of beef, lamb, and poultry because of its Green pro PETA policies. There are senior members of Obama admin who believe veganism is the answer. My friends who raise livestock feed their herds special diets that increase their methane output.

So my advice is fart more, eat more red meat and buy the vehicle you want because soon your freedom of choice will be limited.
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Unread 08-16-2013, 07:37 AM   #21
Kev M
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Quote:
Originally Posted by Dave2002ti View Post
Some automakers make replenishment of the Urea a dealer trip since the computer must be reset. We dont know with Fiat. You just cant dump in the fluid from the parts store since the vehicle goes into limp home mode unless the computer is reset.
I continue to predict that most (all?) manufacturers using DEF are not going to make the vehicle go into limp home based on mileage alone, meaning that they are going to use some form of level or pressure sensor on the urea tank/injection system - ergo - if you anticipate the need for fluid and top it off before a level sensor triggers a warning you won't ever need to return to the dealer for a reset.

But time will tell...
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Unread 08-16-2013, 08:26 AM   #22
hemispin
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Quote:
Originally Posted by Kev M View Post
Well, my point is so are we on our V6, so there's no reason to assume either you or I wouldn't also get more than city rating from a Diesel right?

I suspect that has something to do with where we live, driving habits, how we use the Jeeps etc.

So a realistic comparison for US should reflect that across the board. No?
I have found that I can easily beat average mpg numbers. Maybe one of the reasons is that I'm not one of those people that mash the gas pedal to get to the red light first. I don't use my brakes nearly as much as most people on the freeway. It's called being alert, and anticipating slow downs. Coasting sometimes and keeping a steady speed helps your fuel economy.

I can't give any info on what the average fuel economy would be for the V6 or diesel. So I gave my best guess. I also used your numbers. Use the comparisons as you like.

Quote:
Originally Posted by Kev M View Post
Ah, we're package/feature whores anyway
I have never liked being forced to purchase something I didn't want. All of the automakers do this. Unless a certain option is dependent on another, I think it should be offered a la carte. Not "you can't get a certain axle ratio unless you buy the automatic climate control", or something like that.

I certainly don't need or want all these crazy features like "auto park" or "radar cruise control". People will become more dependent on them and even less skilled at driving than they already are.
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Unread 08-16-2013, 08:30 AM   #23
hemispin
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Originally Posted by nyrhockey23 View Post
His screename isn't Hemi"spin" for a reason, ya know.
Thanks for not giving me any credibility whatsoever. I'm experiencing a 19 mpg average for my first 3000 miles on my Jeep. But I used a lower figure of 18 mpg for the comparisons, which is more than 5% less. Yea, I'm trying to skew the numbers.
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Unread 08-16-2013, 08:32 AM   #24
NDSU_Bison
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Many people are in a Chrysler affiliate program which means they pay no more than 1% less than invoice so I used the invoice prices when doing a similar comparison a few months ago when gas was $3.55/gal and diesel was $3.94/gal.

I tow an RV so I'm only considering the Hemi or diesel. If the Hemi averages 18 MPG and the ecodiesel gest 24, the fuel savings over 62,000 miles at the prices above (with diesel 39/gal higher) covers the extra cost just for the engine alone. I'd probably end up getting the tech package anyway so that helps tip the scale towards the diesel for our needs. The only big service bill associated with the CRD was covered under an extended warranty when the swirl valve had to be replaced.

Then there is the added benefit of running biodiesel to support local farmers and our local biodiesel refinery. Chrysler says the new diesel is rated for B20. The 2008 CRD I have is only rated for B5 and I've run B99 most summers and haven't had any fuel issues over 128,000 miles.
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Unread 08-16-2013, 08:34 AM   #25
Dave2002ti
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Not sure if I would trust

Quote:
Originally Posted by Kev M View Post
I continue to predict that most (all?) manufacturers using DEF are not going to make the vehicle go into limp home based on mileage alone, meaning that they are going to use some form of level or pressure sensor on the urea tank/injection system - ergo - if you anticipate the need for fluid and top it off before a level sensor triggers a warning you won't ever need to return to the dealer for a reset.

But time will tell...
Its that simple. I cant remember if BMW and Mercedes base it mileage or urea level. Please auto makers are out there to make money if they can get you into for a service they will. More parts sold and who knows you way walk through the showroom and fall in love.

Some auto makers make changing the in cabin air filter easy and others you have to disassemble half the dash ie older Accords. It used to be easy to change spark plugs on a vehicle ie 1960's and 70's GM V8's and VW I4's. Now its a royal PITA. All you used to need was a torque wrench, ratchet extension, spark plug socket and anti seize.

If I towed a trailer I would get the diesel over the V8. Would be interesting to find out how much profit Fiat makes on a diesel GC vs a V8 or GC. I prefer naturally aspirated to turbo. I like engines that will rev to 9000 rpms with very small power bands.
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Unread 08-16-2013, 08:45 AM   #26
Dave2002ti
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Support Large Corporations

Quote:
Originally Posted by NDSU_Bison View Post

Then there is the added benefit of running biodiesel to support local farmers and our local biodiesel refinery. Chrysler says the new diesel is rated for B20. The 2008 CRD I have is only rated for B5 and I've run B99 most summers and haven't had any fuel issues over 128,000 miles.
If the local farmers are using crops that can be used to feed livestock and poultry are you doing is driving up the cost chicken, beef, pork, and turkey they may or may be benefitting. As a result its driving up everyones food costs. Depending on where you live biodiesel maybe difficult to find. Its not readily available in Northern Virginia. Out of 6 biodiesel station in VA 4 require key cards. The closest is 20 miles from my house and its the only one in NOVA. Corn should only be used to feed livestock and poultry but its most important use is make liquor. Corn should never be used for ethanol or biodiesel.

Is biodiesel compatible with emission system on the 2014 GC diesel?

Last edited by Jackal01; 08-16-2013 at 07:36 PM.. Reason: FIFY again
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Unread 08-16-2013, 08:53 AM   #27
Kev M
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Hemi, I think it's a good and valid discussion and I appreciate you putting it together. Don't be bothered by minor challenges to the data, that's natural.

That said:

Quote:
Originally Posted by hemispin View Post
I have found that I can easily beat average mpg numbers.

<snip>

I can't give any info on what the average fuel economy would be for the V6 or diesel. So I gave my best guess. I also used your numbers. Use the comparisons as you like.
I'm just pointing out a slight bias in your "best guess" as it wasn't consistent (showed a slight conscious or subconscious bias toward the Hemi).

I.E. If you, as you say, "easily beat average mpg numbers" there's a decent chance you would on other motors in the same vehicle (or even on other vehicles as well) no? Fair assumption?

To be honest, my wife usually DOES NOT BEAT (or even MEET) mpg numbers, so I'm pleased as punch that she's managing to keep it up to and above 18 mpg on the V6.

The woman used to struggle to keep a Mini Cooper S in the mid twenties with MOSTLY highway.


Quote:
Originally Posted by hemispin View Post

I have never liked being forced to purchase something I didn't want. All of the automakers do this. Unless a certain option is dependent on another, I think it should be offered a la carte. Not "you can't get a certain axle ratio unless you buy the automatic climate control", or something like that.

I certainly don't need or want all these crazy features like "auto park" or "radar cruise control". People will become more dependent on them and even less skilled at driving than they already are.
Well, to be fair, I'm not generally a fan of too many electronic nannies, but I do like gadgets and I do understand why manufacturers bundle packages. I don't get this particular requirement and why it is tied to the diesel motor (that might be a mistake on Jeep's part as it seems like it will discourage sales).

But I do understand why it happens.


Quote:
Originally Posted by hemispin View Post
I have found that I can easily beat average mpg numbers. Maybe one of the reasons is that I'm not one of those people that mash the gas pedal to get to the red light first. I don't use my brakes nearly as much as most people on the freeway. It's called being alert, and anticipating slow downs. Coasting sometimes and keeping a steady speed helps your fuel economy.

I can't give any info on what the average fuel economy would be for the V6 or diesel. So I gave my best guess. I also used your numbers. Use the comparisons as you like.



I have never liked being forced to purchase something I didn't want. All of the automakers do this. Unless a certain option is dependent on another, I think it should be offered a la carte. Not "you can't get a certain axle ratio unless you buy the automatic climate control", or something like that.

I certainly don't need or want all these crazy features like "auto park" or "radar cruise control". People will become more dependent on them and even less skilled at driving than they already are.
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Unread 08-16-2013, 09:10 AM   #28
hemispin
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Quote:
Originally Posted by Kev M View Post
I'm just pointing out a slight bias in your "best guess" as it wasn't consistent (showed a slight conscious or subconscious bias toward the Hemi)
Call it a slight bias if you want, but I see where you're coming from. It's still a best guess. I did casually look at some mileage reports on fuelly.com, but those results are scattered at best. I don't own the V6, or the diesel. I think the 19 mpg real world average for the V6 is realistic. It may get a little better on average, but I don't know.

To be honest with you, I'm surprised I get 19 mpg with the V8. Most of my friends that own Durango or Dakotas with the 5.2 or 5.9 V8 get terrible mileage, like 10-13 mpg. A neighbor's V8 Explorer gets 14 mpg. My wife's previous Explorer with the 4.0L V6 got about 18 mpg. Then again, my other neighbor's 2wd Dodge crew cab 1500 truck with the hemi got 18 mpg average.
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Unread 08-16-2013, 09:16 AM   #29
Kev M
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Hey we all have biases, no real harm.

Again, I hear what you're saying and I attribute your mileage to YOUR unique usage patterns/environment. Others may or may not get the same results. But that's why I was calling for the comparison to use the same relative efficiency across the board, because drivers with similar environments/habits SHOULD see similar results yes?

We're seeing similar results, from similar usage (trying to get decent mileage) and arguably in an environment that is not conducive (lots of hills, lots of stop signs/lights, famously poor fuel quality etc).

I CAN make the mileage numbers drop if I jackrabbit a lot, but honestly the Jeep just isn't fun to drive that way for me so I'm not motivated to. Maybe I would be motivated too if I had the Hemi - which would make for a bigger difference between the two for me.

Considering my wife's history with mileage vs EPA estimates I feel strongly she'd be getting closer to 14 or 16 if we had the Hemi (see Mini Cooper S reference).
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Unread 08-16-2013, 09:22 AM   #30
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Nice, but IMO, your averages for Hemi MPG are quite high. I've had 2 Hemis, and now a Pentastar. My Pentastar always averages 4-5 MPG better than the Hemis. Granted, I know the '14 8 spds are supposed to get better, but I can guarantee the Pentastar will get more than +1MPG better average with the same driving style. If it didn't, it would be worthless. Per window stickers, Combined EPA on the '14 V6 is 19 MPG. , Combined on the '14 Hemi is 16MPG.
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