2014 Jeep Grand Cherokee - Diesel!

[scubatech]

Other than Hudson I have not heard any good fuel mileage #s from Dodge's 6.7 liter Cummins. MPG figures have been pretty dismal. The guys I know that are running them have been reluctant to admit how bad they are. They quickly change the subject with, "But you talk about power! Man that thing is strong/fast/quick/powerful." Everyone I know that is running the new 6.7 "upgraded" from the 5.9 Cummins. Happiness is where you find it.
I read last night that the Ram 1500 won MotorTrend Truck of the Year. This was based entirely on the merit of the new 240 HP diesel that it shares with the Grand Cherokee. Motor Trend loved the way this diesel performed in the Ram pickup and their MPG #s were very impressive. This diesel is getting better mpg figures than anything in the 1/2 ton pickup segment.

Just food for thought, most of the gas-burning vehicles with automated fuel mileage readouts are moderately to very accurate. None of the diesel trucks I have dealt with have been even close to accurate. This has been true regardless of brand. Hand calculating the mileage is the only way to know.

This is the 7th year of manufacturers running DPF's. I think the mileage will come up every year as they keep refining after treatment components. Even BMW is into with their performance models. Urea is mandatory now even though the Cummins passes without it. 2006 was definitely the year to get if you want to play with tuners and non ctalytic exhausts. I couldn't find a low enough mileage one to suit me or I would have gone that route. Diesels resale well out here in the Rockies.

 

[not2shabby]

Very nice - I've got a '94 Grand Cherokee that my daughter is driving right now. It's got the 5.2 - 318 in it, goes anywhere, but mpg is not one of it's strong points. I've been hunting for one of the '06 - '07 Grands with the Mercedes 3.0 CRD.
My current daily commuter is a 2010 VW Jetta TDI. Only 140hp, but 240ft/lbs of torque at 17rpms according to the spec sheet. I've put 22,000 miles on it, and my average mpg to date is 41.8mpg - that's calculated and not trip computer. You can drive this thing like you're hair is on fire and it still gets 40mpg. It's a blast to drive...

Even with the off set in fuel cost, the TDI is more economical than what a gas car of the same size would return, and the TDI step out and go.

I've got an '10' Jetta sportwagen TDI with the DSG tranny. On the highway I get anywhere from 39 to 46 mpg depending on speed, terrain, etc. On my 8 mile work commute I get around 36-37. Pulling a 4x8 flatbed trailer with 2 dirtbikes (around 900-1000lbs) I still get 31-33 mpg down in the Hocking Hills area.

The turbo lag does take a little getting used to, there's a 'flat spot' from the 800rpm idle up to about 1200rpm when the turbo kicks in. I've found it works best leaving a stop sign if I anticipate when I need to accellerate. If I take my foot off the brake a second or so before I need to zip out, it lets the car start rolling just a bit and it's easier to get into the zone. A few times before I figured it out, I burned some rubber trying to squeeze into traffic!

As for diesels being dirty...I can run my finger around the inside of the tailpipe and it's clean as a whistle! It's got over 100k on it now, too. Try that with your gasser!

The downside is the maintenance...the DPF(diesel particulate filter) in the exhaust will likely need to be replaced, cleaned, (or omitted) at some point, and I'm sure it won't be cheap. I hate to admit I'm leaning toward omitting it when it plugs up and dies. Malone tuning makes a DPF delete kit and supplies a tune that bumps up Hp and torque considerably while supposedly increasing mpg. Then you never have to worry about your DPF filling up again...hard to argue with that. I guess it only puts out a little smoke if you really stomp on it.

One more advantage to diesels I haven't seen mentioned is the longevity. I'm gonna try and get at least 500k miles outta this beotch!

 

[Hudson]

Redfish, the naysayers of the Ram 6.7 seem to be the Gen III, up to 2012. Lots of issues with regen, and most look to mod to improve the mileage, at the risk of black soot belching results. The chatter on the RAM forums is that the Gen IV, with it's DEF, seems to be avoiding the regen issues of the Gen III and getting higher mpg than an un-modded version. The 5.9 engine draws raves, but it is lower in power and modern features than the new 6.7. The Gen IV crowd is pretty happy so far.

Agree on the gas mileage accuracy. Computer is about 1 mpg higher than hand calculations.