I'm not going to get into the environmental aspects - your decision.
Most of our travels have been in gasoline vehicles, although we've used diesel off and on in various parts of the world (Argentina, Europe, Algeria, Oman) and on our 10 month Africa trip used a diesel LC80. So, we have experience in North America, Central America, South America, Europe, Asia, Africa, and Australia.
A few things to consider:
- we've personally never been unable to obtain gasoline or diesel anywhere EXCEPT for Venezuela (only 1 in 50 stations had fuel, and the ones which did have lines of between a few hours and a few days) and Argentina (a few stations in Patagonia didn't have fuel at times). In both cases the shortage was both for diesel and gasoline, so no benefit having one versus the other.
- we've never heard of others being unable to obtain gasoline anywhere in the world - all over the world motorbikes are a fundamental means of transport and the market meets this need (formally or informally).
- we HAVE heard of others being unable to obtain diesel (in East Africa) - so although trucks (i.e, heavy transport vehicles, not pick-ups) usually operate on diesel it doesn't mean that you can always find it.
- gasoline quality can vary (Venezuelan gasoline is notoriously poor quality for example) however this has never given us a problem since the engines in the vehicles we've used in the last decade are smart enough to adjust for fuel octane.
- we prefer gasoline from the point of view that diesel is a lot less easy to clean up in terms of getting it on your hands, clothes, gloves, etc. We much prefer gasoline as a "clean" fuel.
- gasoline is flammable whereas diesel needs higher temperature then typical ambient to catch fire
- if travelling in very low temperatures diesel may present a challenge - typically in extreme latitudes the diesel sold is modified to handle low temperatures, however if you do end up with "solid fuel" you're in trouble.
- it used to be considered better to have a diesel engine for wading rivers (for example) however today's diesels are more complex in terms of electronics and can be affected, and gasoline engines today have better insulation. We've never had an engine stall when wading.
- diesel engines are typically stronger, however they are also more expensive. More to the point, if you treat any engine with care, and maintain it properly, it's not going to break - I have never yet had any engine, diesel or gasoline, fail. Yes, you can wear out valves or injectors, however a "broken engine"? No.
- I see a lot of threads posted by people wanting to disable DPFs or other emission control systems on diesels. This tells me a couple of things - one is that the diesels concerned present problems as built, and the other is that some people are willing to run their vehicles without complying with emission control regulations, which might result in fines in many countries (without getting into the ethics of the situation).
- if you plan to travel to some parts of the world running a diesel engine may impose significant restrictions - many diesel vehicles are already banned from entering Paris during the week for example, and restrictions are going to become more stringent. The solution is obviously to park outside the city and take a 'bus, however if you need to have maintenance done on the vehicle you will have a problem.
AS far as we're concerned we are not interested in a diesel vehicle, see no benefit in diesel versus gasoline, and believe that diesel vehicles are going to become progressively less acceptable over time.
