Having recently purchased a new diesel car, I am often asked “is it worth it”. The question is based on some combination of three basic presumptions. First, it is presumed that diesel cars cost more when compared to traditional gasoline automobiles. Second, it is presumed that diesel fuel costs more than traditional unleaded gasoline. Finally, it is presumed that diesel cars in some way under perform gasoline automobiles. Thus the question is really: “Given the presumed problems with diesel cars, are they worth it?”
This post is based on my recent experience with the new BMW 335d. Of course buying a BMW is not exactly a thrifty thing to do… but I assure you it was within my means. Besides, if you can’t spend the money you save on things you want every now and again, what’s the point? Anyway, I purchased a new 2011 BMW 335d in the fall of 2010. I made my decision based on the premise that gasoline prices were sure to continue to rise (You can’t print trillions of dollars and not have the price of commodities not go up) and that by burning fuel more efficiently I would be not only saving some money, I would also be “helping the environment”. That and my wife said I was too young for a 5 series.
Here is how things have broken down.
First, the 335d actually cost me about 10% less (~$4k) than a similarly equipped 335i. Despite the fact that the 335d has a base MSRP of $2k more than the 335i. This was the case for several reasons:
- BMW provides a $2500 to $4500 “eco-credit” depending on the month (In my case I got $3500).
- BMW provides generous finance between 0.9% and 4.9% (In my case I got 0.9% for 3 years and yes sometimes debt is “ok”)
- The government provides a $900 Tax Credit for the purchase of a certain fuel-efficient vehicles.
- I was able to get a very good deal by using the “Internet sales” division of several dealerships.
Worth It #1 – At least in my case, the diesel car actually cost less.
Second, while diesel fuel does cost more than unleaded, it doesn’t cost that much more. Where I live at last check, a gallon of diesel goes for $4.05 while a gallon of premium unleaded (required by the 335i) goes for $3.99. So the gas is indeed a full 2% more expensive and it is 8% more expensive than regular unleaded at $3.79.
But based on my driving experience for the last 2500 miles, I am getting an average of 31.3MPG with my car. BMW advertises the 335d as getting 23MPG city and 36MPG highway… I am seeing about that. If you assume a 50/50 mix this averages to 29.5MPG. The 335i on the other hand is advertised as getting 17MPG city and 28MPG highway or assuming a 50/50 mix an average of 22.5MPG. If we give the 335i the same mix as me, this would mean an average of ~24MPG.
This means that based on BMW’s numbers and some of my own experiences the 335d gets about 24% better gas mileage. It doesn’t take a math wizard to see that if the fuel only costs 2% more and you get 24% more bang for the buck it the diesel is the way to go. Base on my driving, this means I will save approximately $190 a year in fuel costs.
Worth It #1 – At least in my case, the diesel fuel actually cost less.
Finally, what do you sacrifice by getting a diesel? Fortunately, the days of the old smoke bellowing diesels have long since past. Today’s new “clean diesels” burn clean with no perceptible smoke from the tail pipe. But the reality is that it depends on the diesel. In the case of the 335i vs. 335d you do give up some 0-60 time (5.6s vs. 6.0s) so if I gun it of the line, it takes me an extra 4/10ths of a second to get there. The 335d is also a little heavier (~250lb), so I imagine the handling may slightly hindered. I will say the car is a BMW and with the M-suspension package I have not noticed any handling problems. The one place the 335d spanks the 335i is in torque (125 pound-feet more than the 335i). I find that this is most noticeable in the 60 to 80 range, where the car is a real sprinter. The only other thing I will say I noticed was an occasional “burning” odor for the first 1500 miles or so, but that has now gone away… I have read this is normal as the car “burns in”. No idea if this is related to it being new or a diesel. So when it comes to sacrifices I don’t really see any.
Worth It #1 – At least in my case, the diesel performs just as well as a non-diesel so we can call this a wash.
Of course you don’t need to buy a new car to save on fuel costs. Consider these tips instead.
This posting is provided “AS IS” with no warranties, and confers no rights.