Petrol vs Diesel: A 10 year urban running cost comparison

[Bushbasher]

I always look at Prados on the road and I reckon it's closer to 70/30 in favour of the TD. Is there currently a bit of a glut on T/D Prados and Hiluxs for sale given the huge downtown in the mining sector? Another 3000 laid off in WA recently with a 1000 told they won't have a job after Christmas (Barrow Island).

[Whitey]

Hey Rusty,

Wow!

An incredible $14000 difference to the most expensive, that is just beyond ridiculous and completely without justification!

Some more perspective, I paid $37000 for my V6 GXL with just under 80000km 6 years ago, it was mint condition, never been off road.

Well I know what I'd be buying!

...it also brings up another point, I've seen the figure of diesels/petrols sold in Australia quoted as 98% diesels. Are you aware of any good sources for reliable statistics of the real ratio? I can't believe that only 2% of Prados sold are petrol!

Best

Mark

[Rusty62]

This is off carpoint today

[Whitey]

Hey Rusty,

Wise words for the way the market is right now!

However, the big difference in 2nd hand price is completely unjustified according to my number crunching above. At best, a 5 year old V6 should only be around $900 cheaper than a diesel, and a 10 year old about $1800 cheaper.

Best

Mark

[Rusty62]

So when buying second hand - go the V6.
Buying new the diesel.
The resale is the killer on the petrol 4wd.

This also applies to the 100 series Sahara Land cruiser. Original cost of the diesel over the petrol was only $10000 more. Now the resale is between $15-25000 more for the diesel. This is of course if you are looking at the whole picture of owning the car.
Lets start talking insurance, rego etc. Do tyres wear out faster on the petrol's when using the extra power? Brakes last longer with manual transmissions.

For me it is about the overall feeling i get from the vehicle i buy. If it was just dollars i would drive a Getz. That's why i have diesels, a 120 series D4D and a 2006 100 series Sahara.

Rusty.

Also we have in the driveway a 2000 Avalon V6 and a 2002 Rav4 with a 2.4 petrol motor. The Avo hasn't been touched other than batteries and brake pads in 10 years. It would be the most reliable car i have ever had. The Rav we bought with a dead motor and a new 2.4 motor import from Japan, brand new in a box is now residing under that bonnet.
Daughter has a 2013 Hilux D4D, and for the rest of my family (it's a big family i'm number 9 of 9) we have 2 x 200 series, 2 x challengers, FJ Cruiser, 2 x 150 Prado D4D, 1 x BT50 (4 cyd), Xtrail, Murano, and several non 4wd cars. I can't really call the last two as 4wd now can i.

[Whitey]

Hey all,

I finally found some historical diesel data stretching back far enough, the source is;

http://www.fuelwatch.wa.gov.au/fuelw...iceSearch.jspx

These are Perth metro prices that I used, and to match the national average trend for 2015 data from AIP, the Perth metro needs to be scaled down by around 4.25c/litre. Poor old folks in Perth are copping it!

Here is what the final data looks like;



As was the case for monthly petrol data, there are enough plus/minus swings to change the calculation substantially.

Recalculating the diesel data on a monthly basis reduces the total fuel cost from $28031 down to $26277, a difference of $1754, or around $175/year back in favor of the diesel.

Adding that back on to the $12/year from the last iteration of the calculation puts the final figure at $187/year saving for the diesel.

I think that is as accurate as the model is going to get, you'll save $187/year or about $15.58/month by running the diesel instead of the petrol.

Best

Mark

[Whitey]

Point 3. Is a very good one. Even a used Prado can be $10,000 more for diesel. So all savings could be lost? Haha......
Lets all sell our diesels & get a v6? Quick before everyone reads this not!
Both very good engines, own & drive whatever you choose for you own reasons, the main thing is you have one!!!

Hey ####,

I think this thread has now confirmed the obvious: there is no real cost benefit for diesel Prado over petrol Prado. They are equal in cost terms. The extra price of used diesels is not at all justified.

I still think many buyers will purchase based on preconceived historical ideas/benefits etc., and a million miles of misinformed nonsense on the internet, but maybe now both types of motor can be looked at with a fresh perspective based on some real world analysis!

I think we should also keep in mind that we wouldn't be having this debate for older vehicles that aren't subject to Euro emission standards. It is very much a modern engine debate, and it is the extra cost of emission standard systems for diesels that brings about the equality between diesel and petrol in this case.

Best

Mark

[Anth120playdo]

Just something to note and not necessary that it needs to be taken into account in the calcs:
1. Petrol prices jumps up and down weekly/fortnightly compared to the more stable prices of diesel. With the large fuel tank in the Prados, there is probably a higher occurrence that the owner can fill up on the low cycle. Thus bringing the fuel price down below the national average.
2. With the diesels, there are additional (recommended) items installed like additional fuel filters, catch can, EGR blocking plate; plus additional activities like EGR clean, sump pickup inspection, Techstream/injector readings.
3. This may not apply to all purchasing scenarios... the petrol is much cheaper to buy 2nd hand. It is however debatable as to how much of this savings will be reflected when the vehicle is up for sale again. If the scenario is that the Prado is bought 2nd hand and then run till it dies, then buying a petrol would be favourable.

Just some food for thought when you're doing your own calcs.

Point 3. Is a very good one. Even a used Prado can be $10,000 more for diesel. So all savings could be lost? Haha......
Lets all sell our diesels & get a v6? Quick before everyone reads this not!
Both very good engines, own & drive whatever you choose for you own reasons, the main thing is you have one!!!

[Whitey]

This is some really good stuff and I reckon it might be fairly helpful to those tossing up which direction to head.... petrol or diesel.....

I would like to hear from those that have an after-market LR tank in a Petrol 150's & what sort of range they get out of it......

Hey Rob,

Dunno if you've read this thread;

http://www.pradopoint.com/showthread...for-150-series

222 litres of petrol at the 15.2l/100km used in the model calculation in this thread would be 1461km range. Nice stuff!

Best

Mark

[Whitey]

Hey again,

Here are a couple of plots from AIP showing the last 40 weeks worth of data, where you can see the cyclical variation of petrol, and the relatively flat curve for diesel;

Petrol



Diesel



As such it appears that the often read statement that diesel variation is pretty flat compared to petrol is true.

Even so, there's probably some small gains to be had on the diesel side by using monthly data in the model, so if anyone can find a source lemme know!

Overall though, I don't believe it will change the conclusion, and any cost advantage of diesel over petrol will be minimal, and probably less than $100/year.

Best

Mark

[rob_macca67]

This is some really good stuff and I reckon it might be fairly helpful to those tossing up which direction to head.... petrol or diesel.....

I would like to hear from those that have an after-market LR tank in a Petrol 150's & what sort of range they get out of it......

[Whitey]

Hey all,

I've now re-calculated the data to include the cyclic price of petrol. This data is sourced from Caltex. Monthly data (for Brisbane) is in red, and the national average is the dashed black line. The data only included the major cities, so I chose Brisbane.



My previous suggestion that there may only be a few dollars/month saving was way off, and you can see that the cylical variation of petrol produces big plus/minus swings compared to the national average.

Previously the total cost for the petrol was $33146 based on the yearly national average. Re-calculating for the monthly data gives a huge difference, with the total reduced to $30156. This is a saving of $2990, or$299/year.

This means the diesel is now ahead by $311-299 = $12/year.

Yes you read that correctly, the diesel is ahead by only $12/year.

Unfortunately Caltex don't have monthly data for diesel, and I can't currently check if there are large enough monthly variations for the total cost of the diesel to be considered unreliable from the national average.

I have read in many places that the price of diesel is always fairly flat compared to the cyclical variation of petrol, but I won't believe this until I see some monthly data.

For the sake of this thread to provide realistic numbers, I'll need monthly data for diesel, so if anyone knows a good source shout out!

If the national average for diesel is truly representative, then the petrol vs diesel race just got a lot closer!

Best

Mark

[Mick2211]

Mark,

2013 V6 GXL auto, no extras fitted, averaging 10.9l/100km (scangauge) mainly open road use.

Regards....Mick

[Whitey]

Hey amts,

All good points to consider!

I mentioned in the first post that the analysis is a bit on the data poor side by using yearly averages. I do have historical petrol data on a monthly basis, but it will take a while to re-crunch the data. If there are any gains for petrol, I'm guessing it's only a few bucks/month.

Regarding all the additional maintenance for the egr system, I assumed that inspection/cleaning etc. was all wrapped up in the $2000 figure that #### provided.

Another interesting point is that the 1GR-FE in the 150 series is more economical than the 120 (by how much 150 owners?), and doesn't have the "old" early model 1GR-FE issues like timing cover leaking (up to 08 models), head gaskets blowing (04/05) etc. Anything after 05, and the 1GR-FE is a very bullet proof looking motor, with a minor number experiencing the infamous timing cover leak.

The DPF system in the new 2.8 is an altogether new and cumbersome beast. Judging from European experience, the DPF system will likely be as difficult and costly to maintain as the old egr system it replaces, perhaps even more costly!

What is apparent from these discussions is that any cost benefit the diesel had over the petrol is negated by a costly emissions control system that ends up costing owners a lot of money outside the normal service schedule.

Best

Mark

Just something to note and not necessary that it needs to be taken into account in the calcs:
1. Petrol prices jumps up and down weekly/fortnightly compared to the more stable prices of diesel. With the large fuel tank in the Prados, there is probably a higher occurrence that the owner can fill up on the low cycle. Thus bringing the fuel price down below the national average.
2. With the diesels, there are additional (recommended) items installed like additional fuel filters, catch can, EGR blocking plate; plus additional activities like EGR clean, sump pickup inspection, Techstream/injector readings.
3. This may not apply to all purchasing scenarios... the petrol is much cheaper to buy 2nd hand. It is however debatable as to how much of this savings will be reflected when the vehicle is up for sale again. If the scenario is that the Prado is bought 2nd hand and then run till it dies, then buying a petrol would be favourable.

Just some food for thought when you're doing your own calcs.