Diesel - Would you rather....E70 vs F15
 

Hey fellow owners -

I wanted to get some input from you, I currently own a e70 x35D and I love it. Although I like new things as well, and have contemplated getting the new 2014 x35d.

I know that I will be keeping this diesel for a while, so that being the case thought if I have a chance to upgrade to a brand new one, this would be the time.

I've got 37k on my current x5d.

Is the F15 that much better with the 8 speed transmission, electric assisted steering, and lighter curb weight?

Pros & Cons insight and personal opinions are welcome.

The eight speed transmission is a big plus IMO.

Less curb weight is always a good thing.

I didn't like the feel of the electric power steering when I tested one.

I wouldn't be rushing to buy an early production model of any new vehicle. New engine, (well, at least the first application of NA emissions controls to this engine), new transmission in this model, and so on. At least the platform is still the E70 platform, but it is the small details that can cause the biggest frustration.

Can't justify choosing a diesel, myself, over the 35i, even with the new lower price premium for the diesel model.

neither... vw touareg or q7 tdi.

Because......

I drove a 14' 328d and absolutely hated the 8 speed transmission. It was always shifting. The 6 speed actually uses the power band and compliments the diesel more.


Sent from my iPhone using Tapatalk

Why would you rather buy a 35i ? Not desirable to me at all. Much more tq on the diesel. Better fuel economy. Better sounding motor


Sent from my iPhone using Tapatalk

It is a question of personal preference and the way the X5 is used.Diesel definitely has more room for tune/improvement.
Especially with a new tune for the X5D/335D coming from Europe in the following months-stage1-320hp/500+tq and still the same great fuel economy.The premium gas now being 30 cents per gallon more expensive than the diesel here doesnt hurt either.
For Audi/VW I may consider them once they start making diesels with aluminum block,i.e. when they finally enter the 21st century.

I am not really attracted to the diesel. I have owned two, not BMW. I recently drove an F15, and if we get one it will likely be a 35i, with the optional BMW performance tune. More revs, more engaging to drive, more fun. I think it sounds better too, but like the last few items, that is personal taste. Diesel model has less horsepower than the 35i, so it's slower, and it just seems a lot less like a BMW to me. Good mileage, but not enough to come out ahead on cost of ownership given diesel fuel prices. Sure it has torque, but that is flywheel torque, and torque to the ground matters more. 35i wins there.

And then there is my wife. She remembers refueling the Landrover Discovery and the Passat, and doesn't want to go back there. I could probably be swayed easier than she could.

I'd say the diesel is always shifting because it has a narrower working rev range. It needs to shift. It does shift nicely though.

On the diesel N57, rated torque is available from 1750 to 3000 rpm, a 1250 rpm range.

On the gasoline N55, rated torque is available from 1200 to 5000 rpm, a 3800 rpm range. That is 3 times the usable rev range, not even considering the higher redline (7000 rpm vs 5000 rpm). Hence, less shifting.

A plus for the diesel is that it has a heaver/stronger 8HP transmission than the 35i.

Yes, the diesel has more flywheel torque in that narrower band. But I think you will find it shifts a lot despite the higher flywheel torque, if you want to keep up with a 35i.

That would be true if both had the same final drive ratio.But they are quite different so your logic is not exactly correct.What that means is that ,just for example,1st gear on the 35i with 8sp tranny tops at ~25mph and the 1st gear of 35D with 6 speed tops~30 mph.With the 8 speed tranny gears on the gas and diesel will end at similar road speed,so both cars will have similar max,speed.
The RPM window you mentioned is for the peak torque.However the 35D have usable range from 1200 to 4500 rpm.in the city cycle I stay between 1300 and 2000 rpm.Sometimes even go to manual mode to upshift quickly.
As I mentioned before,the 6sp is a downside for the E70D,but not that huge.
And yes,the wheel torque is what matters.That is the reason why gas engine will be always faster than a similar diesel engine.Many people dont realize that the final ratio is actually a torque multiplier.