Diesel engines are usually made from iron.
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Pump Price Difference - Petrol vs Diesel
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Diesel engines are usually made from iron.
Soldato
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I believe they have to be beefier due to the higher compression they use.
What's your source for that? Checking various figures it's as low as 1400 for the 320i and 1495 for the d.
Parkers
I'd be surprised if it was that low TBH, my F30 330D (auto only) was 1560kg. That being said, book weight varries a lot across the interwebz, as the 335D seems to be around 1700+ kg. 140+ extra kg seems a lot for two front driveshafts and an extra turbo...
And unfortunately there's no petrol equivalent that would come anywhere remotely near the blend of performance and economy the 30D and 35D engines offer...
And unfortunately there's no petrol equivalent that would come anywhere remotely near the blend of performance and economy the 30D and 35D engines offer...
Caporegime
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Still impressed with my leggy 530D, decent amount of grunt, 50mpg plus on a long journey. Not sure where to go next but suspect it'll be a something similar.
Soldato
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What economy do you get vs what a 330i would get?
Soldato
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Soldato
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The 340i can get impressively close to the economy of the 330/335d, after the anti diesel press a lot of owners have made the switch and one who tracks all his fuel usage only dropped 3mpg from a 335d I can’t remember the exact numbers but it was around 40mpg to 37mpg, this is over dozens of tanks of fuel recorded at the pump.
I’ve driven a few models with the 6 cylinder petrol and all have managed to get in the 40s driven sensibily
Nothing comes remotely close, I was quite dissapointed to see how much worse my A4 3.0 tdi was especially around town.
The thing is a 330D gets 40+ MPG in mixed conditions regardless of how you drive it, a 330i is quite efficient for a petrol, but still doesn't come near if driven one behind another. If you're nursing the 330i you'll get 40+, yes but if you're having a bit of fun you'll quickly get aproach 30. The 330D will even show you over 60mpg if you're being conservative (I had mine show an 80mpg average over a 20mile stretch of 50mph limited road section) and no matter how much you rag it around it will refuse to drop under 40 unless you only make short town trips.
This takes some very, very specific circumstances, perhaps a high mileage broken thermostat (most are tired, and hardly anyone bothers replacing them despite being £35 from BMW) and short trips where the diesel takes a bit longer to get warm. The 335d will also suffer a minor (say 5%) mpg penalty do to being xdrive only, whereas all 340i are RWD.
However, the moment you have a look at actual averages it very quickly becomes 29mpg vs 36mpg. 500L of extra fuel at a yearly 15k mileage is not the end of the world, but is not exactly insignificant either.
Actual averages of 335D: https://www.spritmonitor.de/en/over...ar_s=2013&power_s=300&power_e=350&powerunit=2
Actual averages of 335i / 340i:https://www.spritmonitor.de/en/over...ar_s=2013&power_s=300&power_e=350&powerunit=2
That is 7.85L vs 9.75L or 29 vs 36MPG.
Soldato
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You need to change to the power to over 320 + or model year to 2016 to catch the 340i with the newer B58 engine this helped gain a few % improvement in MPG over the older N55. Doing this an the average is 9.39 (30mpg), interestingly moving the model year forward to 2016 to match the 340i the 335d drops to 8.33 (34mpg) , I wonder if BMW did some software changes following VW dieselgate.
I always find the best comparison is when the same owner changes car, most 340i owners don't buy them to drive slowly and many diesel owners buy for economy are likely to drive slower. My experience of going between x40i and x30d or x35d is about 5-7mpg which with the current 8-10p between petrol/diesel isn't a huge cost difference for my 10-12k a year. I plan on swapping my 535d for a 540i so that will be a good comparison.
Soldato
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Was 6p diff when I filled up yesterday. Swear it was 5p last time (10 days or so ago), because I am pretty sure the premium unleaded was same price as the diesel, and the normal unleaded was 5p less.
Annecdotal of course but I was told and this seemed to be borne out when I changed my commute that diesels run far more efficiently when cruising, but take a comparatively high hit to MPG when accelerating
Where as petrol are less fuel efficient to start with (contains less energy per litre to start with), but suffer less of a hit from the acceleration.
So the usage would vary based on the type of driving. This seems to be backed up by my personal experience where my diesel MPG dropped a lot (like 20MPG) between cross country and cruising, where as my petrol drops more like 10MPG.
At my last place our fleet manager accused a lot of our london diesel drivers to be stealing fuel as the indicated MPG was massively below the listed, his basis of comparison was the petrol MPG vs book.
It was later proven that it wasnt a fuel stealing collective but just the way the traffic drove (fleet manager was based upt north so didnt realise how badly you had to drive in London constantly)
Annecdotal of course but I was told and this seemed to be borne out when I changed my commute that diesels run far more efficiently when cruising, but take a comparatively high hit to MPG when accelerating
Where as petrol are less fuel efficient to start with (contains less energy per litre to start with), but suffer less of a hit from the acceleration.
So the usage would vary based on the type of driving. This seems to be backed up by my personal experience where my diesel MPG dropped a lot (like 20MPG) between cross country and cruising, where as my petrol drops more like 10MPG.
At my last place our fleet manager accused a lot of our london diesel drivers to be stealing fuel as the indicated MPG was massively below the listed, his basis of comparison was the petrol MPG vs book.
It was later proven that it wasnt a fuel stealing collective but just the way the traffic drove (fleet manager was based upt north so didnt realise how badly you had to drive in London constantly)
Soldato
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It was 6-8p locally before the super markets dropped the prices, Asda dropped to £1.23 for petrol cheapest diesel is £1.32
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All 340i are B58.
You need to be under around 20 to not have known. It was the case in the 90 and possibly even early 2000s.
Then again my dad owned a diesel pickup so maybe thats why I remember. I guess if you weren’t associated with others that used diesel or used it yourself you wouldn’t have cared.
Soldato
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When i went to Gibraltar a few years ago diesel was quite a lot cheaper than petrol but i guess its not taxed anywhere near as much.
It really depends on driving style and conditions, but in my experience cars from the same generation with similar power will still have quite a gap, especially if you have a bit of fun. Your comparrison would be unfair, the old F10 535D will either have an ancient M57 or slightly newer ish (but still 2008 introduced) N57 engine if it's a later one. That, combined with both theromstats being tired and not warming up properly might get you close to 540i mpg. A direct comparrison would be between a 540D, but it seems there's no option for it in the UK...