Thanks for the information, both this time and the last.

Question about the new speedpass - will they deny the application for a new wand, if you use a card already connected to a wand?

The Speedpass deal is a good one. Thanks for the info. I'm always up for $20 of free gas. I wonder if that card can be used for other Exxon/Mobil purchases in the store. I'm gonna find out!

If you are truly cost conscious should you be skipping the XOM stations and fill up at the (usually) cheaper independents?

Besides ... speedpass is RFID based ... eeeew (www.spychips.com)

I drove clear across the country and found Exxon/Mobil to be competitive in the majority of the states.... and I was really looking hard for cheap gas. If you find an Exxon/Mobil across the street from one of the grocery stores selling gas or a truck stop also selling unleaded, you will find some of the best prices in town (depending on the market.)

As for the independents, it often depends on the markets. Some of them sell crappy gas filled with water, some of them aren't really that cheap, and others don't accept credit cards. I save 5% on gas purchases using my credit card, so unless the station takes credit card, it generally isn't a great deal for me. I get about 13 cents back per gallon just by using the credit card. Also, if you live in FL, LA, MA, NC, NJ, RI and SC, it doesn't matter if Exxon/Mobil is the cheapest, because just by signing up you'll get $20 back right away. I am jealous!

I've been doing research into importing a diesel smart fortwo CDI from Canada, and enjoying 50+ MPG regularly... but alas, the EPA and DOT are about as forward thinking as the TSA.

And hybrids are a joke if your commute is all freeway outside of rush hour.

There are a few dealers offering SMART cars in the US - I saw an article last week, I think in USA Today. It indicated there is a lot of pain and expense to make the necessary changes to be allowed to sell the car in the US and the mileage suffers as a result. They also mentioned the huge waiting list most dealerships have for the vehicle (only approved/offered in a few states so far)

combine trips, live closer to work...

wait till technology comes up with
something economically feasable...

I think about this issue a lot since I commute about 150 miles per day, using $300 a month worrth of gas. I live in Michigan.

The best strategy I have found is with Speedway. They have a cobranded credit card that gives a 4% rebate on Speedway purchases. When you buy a Speedway gift card (refillable, any amount) you also get a discount of $2 per $50 spent (another 4% discount.) Once a month, I use the Speedway CC to load up my gift card with $300, which costs me $288. Then I receive a 4% rebate on the $288 ($11.52) for a total price of $276.48 for $300 worth of gas.

Then I use my Speedy Rewards (loyalty) card to add up points. I am about to reach 34,000 points ($3,400, although they have bonuses for stuff like milk so I didn't actually spend that much) which will get me a $50 Speedway gas card.

This is the best I have been able to come up with. However, what I really want is a diesel car (which will apparently have to be a VW) so that I can fill up with biodiesel, thus buffering me from the fluctuations of the petroleum market, creating less environment-destroying pollution, and reducing my personal dependence on oil which results in the US giving money to terrorists. I really want that Jetta.

The only ones offered in the US are the gas ones, which are nowhere near as efficient as the diesels. I'm looking at a diesel import from Canada... Florida makes it easy to register and title a canadian vehicle, or just keep it with Canadian registration. It's an easy days drive to Windsor.

That easy is definitely relative, I have problems having to drive from DC to PA.

I leave after breakfast to DC and I'm there just before dinner

If I could earn FFM's for road trips, I'd definitely be enjoying AA even more

The cost of whichever fuel at the pump is the sum of 5 elements:

- crude oil cost (from extraction to the refining plant)
this is about the same for gas and diesel

- refining cost
this is more complex
let's say I can refine 1 unit of gas for $1
then I can refine 1 unit of gas + 1 unit of diesel for $1.20
but if I only want to refine 1 unit of diesel that'll cost me $0.90

- distribution (from the plant to the pump)
same for gas and diesel

- taxes
in Europe diesel is taxed much less than gas.

- oil companies (and sheik, etc) margin.

Historically, Europe and US have followed different paths.
In Europe taxes were the largest contribution to total price. Diesel, being used mostly for commercial trucks, was not taxed as high. As a consequence, when gas prices shot up in the 70's, European automakers started to push diesel cars.
In the US taxes are lower and diesel and gas cost about the same. As such, diesel engines for private use are still quite exotic.

So the correct answer is that, bar artificial components (taxes and gain margin), diesel and gas cost about the same and are still quite cheap.

Diesel engines give more mileage per fuel unit.
Gas engines are naturally better performing.
Diesel engines generally pollute more.

If you ask me what's the best way to save on gas: get a small car. Smaller engines and smaller cars weigh less. This is the single most important factor in fuel economy. Besides, a small car costs less and you'd save there too. By small, of course, I mean European small: 1 liter or less engine, four seats, gross weight under 1600 lbs., 75 mph top speed.
Why so many feel the need of commuting to work on a 3-liter monstrosity beats me, especially considering that Americans are generally unskilled drivers.

I won't necessarily agree about deiesels being the more polluting... the new generations of diesels on sale in Europe and Japan are among the cleanest engines around. You should check out some of the Euro CO2 ratings... the dirtiest car sold in Europe right now is the Gas powered Dodge Ram (yes... someone at DCX thought it was profitable to export them)

I agree. But that's because manifacturers spent more money on cleaning up diesels. From a thermodinamic point of view, a gas engine has better, cleaner combustion, so you can't beat that. Of course, it all depends on how much one is willing to spend and what kind of emission control parametrs are imposed.

I totally agree with you on the first point... on the second point, I really don't think you can limit this to Americans. I think there are plenty of crappy drivers the world around. In general, I believe there are fewer automobile deaths (as a percentage of total mileage driven) in the U.S. than in most other countries. The reason we have so many accidents in total is because we drive so much compared to other countries, where gas and cars are more expensive... plus the U.S. is a huge country. But I think the percentage of crappy drivers will be pretty much the same in most modern countries.

The question here shouldn't be about pollution per gallon, but rather pollution per mile. Even if gasoline produces fewer combustion pollutants per gallon, gas engines are typically less efficient and hence require more gallons to go the same distance as a diesel engine. Thus, the relevant question is whether the gas or the diesel engine produces more pollutants per distance driven. Even in this case, gas may ultimately be less polluting, but only if the manufacturers actually implement better pollution control, which in this country doesn't seem to be likely anytime soon.