2014 Jeep Grand Cherokee Summit Test Drive

A Tale of Two Engines

In a Nutshell

With apologies to Charles Dickens, "It was the best of times; it was the best of times." I say this because I have spent the past week driving two amazing SUVs.  They both happened to be 2014 Jeep Grand Cherokee Summits; however, one was endowed with a 3L Ecodiesel engine, and the other, a Pentastar 3.6L VVT V6.  I'm sure you'll want to know which came out on tops in my books, but that will have to wait until the end of this review!

Rolling Off The Lot

Jumping out of the cockpit of the Ecodiesel and directly into the 3.6L Pentastar and tackling similar routes and environmental conditions as I had in the other gave me a quick and dirty opportunity to compare the two engines.  The vehicles, otherwise, were almost identical in spec, even the same color - the first time my wife got in to the Pentastar-equipped SUV she didn't even realize I had switched vehicles!

Leaving the dealership in the Pentastar, there wasn't the now familiar  rumble of the Ecodiesel which has a certain 'gravitas' and latent power that makes you take it seriously!  Reaching the open roads in the Pentastar however, I felt a sense of freedom and playfulness that I hadn't felt in the Ecodiesel, a feeling like being 20 again, light on your feet with nary a care in the world.  This feeling was enhanced even more when I put the SUV into 'Sport Mode', which you do by tapping again on the electronic shifter.  I don't know why, but this rather easy, innocuous motion nostalgically transported me back to the days I had to double-clutch the old 50s vintage International half-ton I used to drive as part of my first summer job building and repairing grain dryers - a happy memory.

Around The Block

On a trip downtown mid-week I decided to park in an underground parkade.  Even though I was sure the Jeep would negotiate the low entrance (5'11") with no problem - I always get a little nervous even in my much lower vehicle - I decided to activate the Quadra-Lift system that allows you to position your vehicle at one of three heights and dropped the chassis to its lowest point.  Now I felt much better about entering the parkade.  Driving in the bush or over rocks I would certainly station the Quadra-Lift to its highest position and feel better about the clearance over rocks and other debris.

It wasn't until I got into a co-worker's vehicle one afternoon to go to a meeting that I realized just how much soundproofing there is in the Jeep.  Going over the same road I had taken that morning I was hearing ambient road noise and vehicle noise that I didn't remember while travelling in the Jeep.  I consciously took note of the noise-level again on my way home after work and confirmed that the Jeep offers a much nicer, quieter ride than many vehicles on the road today.

A couple of days later I got the opportunity to really get to know the Adaptive Cruise Control feature which automatically adjusts your cruising speed to maintain a preset distance between your vehicle and the traffic ahead.  This feature takes a little getting used to.  My penchant is generally to cruise up to the vehicle ahead a little more aggressively; a maneuver meant to get them to move over (multi-lane highway) or be prepared to be overtaken (single lane highway).  Nevertheless, I can see the virtue of this feature on a long inter-city haul when the traffic is choc-a-bloc.

Bringing It Home

I thoroughly enjoyed driving the incredible Grand Cherokee in two of its three award-winning engine iterations.  I didn't have the pleasure of driving the 5.7 L gas engine but could definitely imagine what it was like having driven the 5.7 L Hemi in the Dodge RAM 1500 not long ago. The 3.6L VVT V6 Pentastar is a multi-award winning powertrain pushing 290 hp and 260 lb-ft of torque and comes equipped with an eight-speed automatic transmission with E-shift.  The towing capacity (when properly equipped) is 2948 kg (6500 lb).  In comparison, the innovative 3.0L Ecodiesel pushes 240 hp but claims 420 lb-ft of torque and has a towing capacity of 3265 kg (7200 lb).  This is the enigma of diesel engines - less horsepower, but far greater torque!

 In terms of fuel economy the gas engine claims 12.4 L/100 km (23 mpg) City and 8.3 L/100 km (34 mpg) Highway respectively.   This is pretty decent. The diesel, on the other hand, is even more fuel efficient sporting 9.8 L/100 km (29 mpg) City and an amazing 7.0 L/100 km (40 mpg) Highway.  This means you can actually go about 1300 km per fill (highway driving)!

The first time I put diesel in the tank, two oddities jumped out at me.  First of all, there is no fuel cap such as on every other vehicle I've driven.  Instead there's a hermetically sealed back flow valve that keeps the diesel from spilling out or evaporating.  Secondly, there's an additional orifice for adding Diesel Exhaust Fluid (DEF) that converts NOx (nitrous oxide) to harmless gases - an environmentally friendly innovation.  This DEF is added about once every oil change (approx. 10,000 km) and is looked after by your dealer-servicing agent.

Another vagary of the diesel vehicle is apparent when you start up the diesel engine in very cold weather and there is a slight delay after you depress the electronic starter.  This is disconcerting at first but once you realize this is a result of the ceramic glow plugs heating up, and that this minor delay is protecting the starter mechanism, then you won't bat an eyelash at it.

The Big Decision

So, in this tale of two engines which engine did I prefer and which one would I buy?  Much to my surprise, I preferred the diesel engine.  The whole experience in the diesel felt exceptionally solid and robust.  I loved the rumble of the engine and the feeling of 420 lb-ft of torque.  Just like we barely tap into the entire potential of the human brain even at our most productive times, we are barely tapping into the potential of the 3L EcoDiesel even at highway speeds.  And call me quirky, but I also enjoyed the light scent of diesel in my garage.

Having said that, I would probably buy the Pentastar 3.6 L VVT V6.  The feeling of freedom and responsiveness is liberating and I love the general playfulness of this vehicle.  Also, I don't pull a heavy trailer or RV and the heavyweight diesel is more than I would need.

I will look back fondly on the past week and remember it as the best of times ? and the best of times!