DIESEL: Is the 4k worth it? It depends.....

[Fraser]

Originally Posted by Barcius

I believe both engines has pros and cons depending on the use you will have for your X5: The gasoline V8 showed less vibration when I drove the US spec in the BMW factory, it is more fun to drive in both city and highway and it has that great V8 sound. Choosing between a gas or diesel engine comes down to what you'll do with the X5 and where you live. If you use your X5 like a car, desire quick, quiet acceleration, rarely haul a heavy load, and you don't plan on keeping it past 100,000 miles, you may want to consider the V8 gas engine. However, if you use your X5 for towing, value good fuel economy, and plan on racking up loads of miles, diesel is for you. Also take into consideration the price per gallon of the diesel in the U.S. is still quite high compare to gas. My V8 is averaging 17mpg with a mix 60% city 40% highway. Assuming the diesel makes 26mpg it represents 52% better fuel economy, but the price per gallon of diesel is also 40% more expensive here in Colorado ($2.80/diesel vs. $2.00/premium) so it is only 8% savings or equivalent to say the diesel mpg drops from 26 to 18 miles per gallon in comparable dollars. Not great of a solution in the U.S. as you can see. Good luck with your decision.

You are doing well getting 17mpg. Either, you are a very smooth driver or, you are very light on the throttle. My experience tells me the 4.8 is more like a 15mpg engine and can easily become a 13mpg engine, or worse without too much provocation. The diesel engine doesn't make the X5 into some sort of crude, long-haul truck, best used for towing. The massive bottom end and mid-range thrust makes for plenty of fun and more instantaneous acceleration than the 4.8.

[Barcius]

Originally Posted by Fraser

You are doing well getting 17mpg. Either, you are a very smooth driver or, you are very light on the throttle. My experience tells me the 4.8 is more like a 15mpg engine and can easily become a 13mpg engine, or worse without too much provocation. The diesel engine doesn't make the X5 into some sort of crude, long-haul truck, best used for towing. The massive bottom end and mid-range thrust makes for plenty of fun and more instantaneous acceleration than the 4.8.

You missed my point. I believe, in the US, the diesel does not add to a lot of savings. Price per gallon here is substantially higher than gasoline (the price gap may increase as the economy rebounds) and the fuel economy difference is big, but does not put a lot of $ in your pocket as it may in Australia. Also taken into consideration that here in the US it is not common to have gas stations that sell diesel mainly in city areas. Therefore, in my opinion since I have driven both US diesel spec and the 4.8, the V8 is the winner in this side of the pond. No vibration, smooth as silk, V8 sound, super fast acceleration etc. However, it may have a niche for diesel here if use the X5 primarily for towing and you may want to keep it for more than 100,000 miles since the diesel is well known for its durability.

[MrX]

Originally Posted by Barcius

You missed my point. I believe, in the US, the diesel does not add to a lot of savings. Price per gallon here is substantially higher than gasoline (the price gap may increase as the economy rebounds) and the fuel economy difference is big, but does not put a lot of $ in your pocket as it may in Australia. Also taken into consideration that here in the US it is not common to have gas stations that sell diesel mainly in city areas. Therefore, in my opinion since I have driven both US diesel spec and the 4.8, the V8 is the winner in this side of the pond. No vibration, smooth as silk, V8 sound, super fast acceleration etc. However, it may have a niche for diesel here if use the X5 primarily for towing and you may want to keep it for more than 100,000 miles since the diesel is well known for its durability.

Agree. Here in America diesel will be a niche market. I am not sure why an Australian is trying to understand more about this market than us Americans.

[jpl]

Agree 100% in Canada, the diesel price way to high in Quebec, more then other province to make a justifictaion on fuel savings, plus don't forget, it needs that new low sulfur diesel, not the common diesel

[jimsaq]

Originally Posted by MrX

Agree. Here in America diesel will be a niche market. I am not sure why an Australian is trying to understand more about this market than us Americans.

I'm interested in how you took fraser's comment as 'trying to understand more about the US market'. He simply made a couple of factual comments about some characteristics of the two engines which have nothing to do with any market in particular.

[Fraser]

Originally Posted by jimsaq

I'm interested in how you took fraser's comment as 'trying to understand more about the US market'. He simply made a couple of factual comments about some characteristics of the two engines which have nothing to do with any market in particular.

Thanks for the support. I'm not "trying to understand the US market" nor am I trying to predict whether the X5 diesel will be a success in the US. All that will play out in due course.

When diesel power first arrived in the X5 in Australia (in early 2003 in the E53) many people were sceptical that buyers would accept diesel in a luxury vehicle. But the diesel engine, and the subsequent diesels in both the E53 and the E70 (we have now had four generations of diesel engines in the X5 in Australia) have proved a run-away success despite the fact that we pay anywhere between 10% and 25% more for diesel than petrol (it varies all the time). And, like the US, not all fuel stations (especially in the cities) sell diesel. For most diesel buyers it's not simply a matter of relative fuel costs and economy, it comes down to the diesel's superior real-world drivability.

[MrX]

Originally Posted by Fraser

Thanks for the support. I'm not "trying to understand the US market" nor am I trying to predict whether the X5 diesel will be a success in the US. All that will play out in due course.

When diesel power first arrived in the X5 in Australia (in early 2003 in the E53) many people were sceptical that buyers would accept diesel in a luxury vehicle. But the diesel engine, and the subsequent diesels in both the E53 and the E70 (we have now had four generations of diesel engines in the X5 in Australia) have proved a run-away success despite the fact that we pay anywhere between 10% and 25% more for diesel than petrol (it varies all the time). And, like the US, not all fuel stations (especially in the cities) sell diesel. For most diesel buyers it's not simply a matter of relative fuel costs and economy, it comes down to the diesel's superior real-world drivability.

Fraser, I do get your point, but each market is different. I do not know much about the market where you are, but I understand the V8 and the diesel versions of the X5 are much more expensive in Australia compared to the US. Therefore the price of admission is very different. For us on this side of the pond, it is probably a harder choice to make. With regards to the diesel performance versus gas, I am still skeptical about it. It is difficult to imagine that a V8 gasoline will not crush the diesel in real-world drivability. Reading what Barcius posted, he test drove both US spec cars in the factory here in the US and most of the drivers voted for the V8 as the better/superior car in most aspects. I believe BMW took the results and priced the diesel accordingly. I can give you my impression once I drive the diesel. I've been racing for years here is the US so I can give a honest and professional feedback once I drive it.

[Fraser]

Originally Posted by MrX

Fraser, I do get your point, but each market is different. I do not know much about the market where you are, but I understand the V8 and the diesel versions of the X5 are much more expensive in Australia compared to the US. Therefore the price of admission is very different. For us on this side of the pond, it is probably a harder choice to make. With regards to the diesel performance versus gas, I am still skeptical about it. It is difficult to imagine that a V8 gasoline will not crush the diesel in real-world drivability. Reading what Barcius posted, he test drove both US spec cars in the factory here in the US and most of the drivers voted for the V8 as the better/superior car in most aspects. I believe BMW took the results and priced the diesel accordingly. I can give you my impression once I drive the diesel. I've been racing for years here is the US so I can give a honest and professional feedback once I drive it.

I think that everything in Australia is more expensive than the US! Current X5 Aussie pricing is:

3-litre six-cylinder petrol: $86,635
3-litre six-cylinder single-turbo diesel: $88,541
3-litre six-cylinder twin-turbo diesel: $105,490
4.8-litre V8 petrol: $121,908

Aussie dollar is currently worth 65 cents US. Six months ago it was close to parity (97 cents).

As for relative performance between the 4.8 and the twin-turbo diesel, in Aussie spec the 4.8 is 0.7 second faster to 100 kilometres per hour (6.5s v 7.2s) and 0.7 second faster over the standing-start kilometre (26.6s v 27.3s). For your reference, 1 kilometre = 0.62 mile.

However, these figures don't tell the whole story. I've driven both the 4.8 and the 35d back to back over an extended period (not just at a customer clinic) and the V8 simply can't match the diesel's huge bottom-end and mid-range power and needs all the revs that it can muster to see off the diesel. By 1200rpm the diesel is already making more torque than the 4.8 ever produces, and the diesel's peak torque is some 20% better than the 4.8 and is produced from 2000rpm whereas the 4.8's peak torque doesn't come on stream until 3400rpm. As a racer, I'm sure that you will appreciate that performance is not just about peak power, but power spread and power delivery. I can't really comment on Barcius' comments because all my experience has been with the Australian models and your models (both petrol and diesel) may be significantly different.