Posted By RichC on February 27, 2006
Motorweek updated their views on the Jeep Liberty CRD. They were impressed with the performance but the mileage was far lower than even most avid diesel drivers could tolerate. Here is a short video clip.
A regular poster that I know from a couple of forums is also a Jeep Liberty CRD owner. His conclusion is that the highway performance is very good, but the city driving is not so great. I’ll include his comment directly below:
What I have found with *our* CRD and driving style and all that, is that the CRD sucks for city mileage. When we have a tank go to 100% city, which for us includes lots of short trips, stopping and go traffic – we get only about 19mpg (per the calculated data). However if we have a tank go to highway miles – that jumps real quick. A 50-50 blend highway to city will bump our mileage to about 24mpg average. We have gotten 28mpg on almost all highway.
Today I had about 50 miles on interstate that I decided to play with. Remember, my EVIC is about 1mpg low, and all of these following numbers are from my EVIC.
The freeway I was on was fairly flat, but not completely. Some small inclines and slightly curvy. A pretty good average interstate. Winds were mostly calm. No traffic mid day rural areas…
I got up to 70mph, set the cruise control, and reset the EVIC fuel economy calculator. I drove 25 miles. At the end of 25 miles at 70 mph my average miles per gallon via the EVIC read 27.8.
I then slowed to 65mph, set the cruise, reset the EVIC and drove another 25 miles. After 25 miles at 65mph my EVIC was reading 31.5 mpg average.
I then exited to a 2 lane country road that was fairly flat as well – for about 10 miles. On that road I set my cruise at 60mph, reset the EVIC. At the end of those 10 miles my EVIC read 33.1 mpg average crusing at 60 mph!
I know that these were fairly short distance tests – for a real test maybe 40 miles each would establish a good solid average. And if my EVIC is reading low like it usually does, then I can get between 29 and 35 miles per gallon highway!
And currently my B20 has 80% winterized diesel. I also use PowerService winter treatment (the white bottle) as an anti-gel and cetane booster. So between that and the B20, I am getting good clean high cetane fuel.
I will have to run more “tests” in the summer with non-winterized B20, B50, and B99.
But my conclusions thus far are:
1. The CRD engine is not a good fuel economy performer in the city.
2. Below 60mph and the engine running parameters and transmission settings make the CRD not as efficient as possible.
3. Between 60mph and 65mph is the “sweet spot” for mileage in the CRD.
4. At and above 70mph you start to see the effect of the terrible aerodynamics of the Liberty, and fuel economy suffers greatly.
For me, 60mph is too slow. 70mph is about where I would like to cruise. But on a long trip – the extra 3mpg by driving 65 could pay off, if you are not pressed for time…
And remember – any accessories you add to the top of your jeep suck fuel economy at highway speeds. Racks, lights, cargo boxes. Some people have shown that the Renegade style light bar alone can decrease 1mpg of fuel economy at highway speeds…