I've had 5 Hilux's in the past 18 years, diesel and petrol. I travel around 30,000km per year.
I did the math between my late 90's 3.0 non-turbo diesel and my early 2000's 3.4 quad cam petrol and the real wold all up cost including maintenance, RUC and fuel worked out at around $0.02/per Km more expensive with the petrol. Performance wise I would choose the petrol hands down. The only mechanical issue I ever had was the clutch went in the diesel at 60,000km. The V6 averaged 12.358L/100km on 91 octane, and 11.668L/100km on 95/98 octane. That said, this was back when the cost of diesel was way cheaper in relation to the cost of petrol. The $0.02 difference probably wouldn't exist on today's prices.
Stepping up to the later model Vigo's, I have had a 3.0 turbo diesel and two 4.0 petrol's. The Vigo is a much bigger and more roomy than its predecessor. The 4.0 is a sweet motor and is what I currently drive.
Fuel consumption is 13.09 on 91, and 13.25 on 98. That said, the speedo is out by 9% so real world is probably more like 12L/100km on 98.
I have just gone up a tyre size and put a roof rack on top but haven't done any economy checks since.
What's your fuel consumption like on the Subaru 3.0? From what I understand they are rather thirsty .......
One thing to consider with second hand later model diesels, with the extremely high fuel pressures they run at now in order to gain power and economy, if something goes wrong with the fuel system you are in for a lot of money. The parts used are generally not repairable and must be replaced. A typical set of injectors run at $2k EACH, and a fuel pump is around $4k, so if you are looking at a higher mileage truck, you need to keep $12k in reserve just in case the fuel system is worn out or craps out. A couple of friends i have are mechanics, and their advise is if you are looking at a >10 year old vehicle, go petrol as the service cost [and risk of a major] is way less.
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