Well, it's time to 'fess up. Several posts ago, I mentioned that I was contemplating the replacement of my 2000 Jeep Grand Cherokee Limited that has been the subject of the majority of my posts in this blog.
The fact is that I did so in November of 2006. Did I buy a Prius? No. Did I buy a Civic Hybrid? No. A Diesel Rabbit? No. An Insight? No. Well, did I at least buy a Lexus 400h Hybrid? Yes. Umm... I mean no.
In the end, after driving several vehicles and looking at many more, I wound up in a Land Rover LR3 HSE. This 6000 pound vehicle has a 4.4 liter engine and gets an EPA estimated 14 m.p.g. city and 18 m.p.g. highway. What a hypocrite, huh? Well maybe, maybe not.
A careful reading of my blog (should anyone wish to engage in such extensive self-abuse) will reveal that I never preached that people should buy vehicles with high mileage ratings, rather, I have suggested strategies for consumption reduction in whatever vehicle was driven. I haven't even, as best I recall, recommended reducing driven mileage though this is clearly the most obvious way to burn less fuel.
Now that that's out of the way, let's talk about why I did purchase the Land Rover. First, it's capable of having seven comfortable seats and converting to five with a very large and functional cargo area. Second, it is an unbelievably capable off road crawler and I have a deep and abiding love for the Mojave, Sonoran, and Great Basin deserts, particularly those areas to which no one (except me) ever goes. I wanted the capabilities of the Land Rover for this pursuit, though I have an old (1989) Jeep Comanche pickup that I have extensively modified for extended desert trips (water tank, lift kit, custom over sized fuel tank, spare battery system, cargo carrier, etc.). But I wanted something in which I could take more than one passenger to the desert, given that I have a family of four. I did not have that family when I bought the Comanche.
Now that I have the reasoning (some will say rationalization) out of the way, what has been my experience so far? I started out driving the LR3 with the same methods I had used in the Grand Cherokee. I was able to achieve a combined mileage of about 17.5 m.p.g. Then, in order to see what sort of diminution of mileage a less strict fuel saving methodolgy of driving might produce, I drove in relatively "normal" fashion for a few tank fulls. For these, I saw an average of about 16.1 m.p.g.
In other words, going from normal driving to extreme fuel saving only produced an 8.7% increase in gas mileage. Remember that going from extreme fuel consumption methods to extreme fuel saving methods in the Grand Cherokee produced about a 58% increase in gas mileage. What gives? It's an interesting question, I never drove the Grand Cherokee in a "normal" fashion, only the two extremes. Is it true that I could have gotten almost all of the benefits I achieved by only going from extreme fuel consumption mode (speeding as much as possible, full throttle takeoffs, etc.) to "normal" mode? I don't have the Grand Cherokee, but I passed it down to an employee. I am going to assume he drives "normally" and see what the average mileage indicator shows.Of course, I'll log it here.
There are several questions I'd like to address in subsequent posts. I'd like to know why the 4.4 liter engine in the LR3 burns more fuel per mile than the 4.7 liter engine in the Grand Cherokee. I'd like to know why I can achieve overall fuel economy dramatically higher than even the EPA highway rating in the Grand Cherokee, but not in the LR3. Is this because of changes between 2001 and 2006 in how the EPA performs its evaluations? Is it the aerodynamics of the two vehicles? Differences in the engines? I'll try to find out.