X5 or X3?

[amacman]

Originally Posted by Fraser

I think that you need to go back to your original statement, ie: "hi, i drive a 2002 X5 4.4i sport auto permanent 4wd , the 2004 onwards have xdrive , this means they usually only drive the rear wheels so that you feel as though driving a rear wheel drive." This is incorrect. Both xDrive and non-xDrive X5s are essentially permanent 4WD vehicles. xDrive X5s don't "usually only drive the rear wheels", they usually drive all four wheels.

Here's a quote from BMW's technical info on (X5) xDrive: "In normal driving situations, the drive torque is distributed in the ratio of 40:60 between the front and the rear wheels. xDrive can also vary torque between front and rear axles depending on the driving conditions and can distributed drive torque briefly to one axle in extreme conditions."

What you X3 handbook says is irrelevant as we were discussing xDrive and non-xDrive X5s.

ok , here is info from the bently x5 manual ,you can see how i reached the conclusion , i don`t have access to the x3 manual right now but read this and see what conclusion you can draw from it .

[Fraser]

I find the explanation in top two photographs ambiguous, if not contradictory. However, the bottom page where it says at the top, "In normal driving .... torque split of approx 40% front to 60% rear" is essentially the same as the BMW tech info I quoted.

[faz]

Congrats on X5 purchase.

I test drove X3 a couple of years after it came out, and I was not impressed. The overall interior didn't have the 'rich' look that I expected from that kind of a price tag, the doors closed with a clunky noise, etc. I was not impressed at all and neither was my wife (and she was the one that wanted an x3.)

Recently test drove X3 again, and had the same feeling. Looked at X5 and bought a used one.

At one of our repairs, the dealer gave us an X3 loaner with M package and navigation... very nice ride for sure... was a lot sportier and faster than our X5, but size wise it was no where near what X5 offers, regardless of the specified volume numbers. (usable volume is different than just volume.) Front seats/rear seat space seemed very much the same as my wife's 2007 328i. It basically felt like a lifted hatchback 3 series. With a car seat in the back, I could not wait to get my own X5 back, even though it didn't have the same speed/sportiness of the X3 loaner.

[amacman]

Originally Posted by Fraser

I find the explanation in top two photographs ambiguous, if not contradictory. However, the bottom page where it says at the top, "In normal driving .... torque split of approx 40% front to 60% rear" is essentially the same as the BMW tech info I quoted.

ok whatever . the explanation of how the system works is there in print for you , if you can`t get your head around it then believe what you want , it`s no big deal , but you are still trying to bullshit what i said so that is why i took pics for people to understand what i said . you are correct in what you say about the 40% to 60% split when it is utilising 4 wheel drive but as i am trying to explain there is much more to the X drive system than just that alone . it is still predominantly rear wheel drive . you can look up the word predominantly in the dictionary if it doesn`t make sense to you .

[Fraser]

Yes, it may be predominately rear wheel drive (ie. 40F/60R) but that's along way from your original statement "the 2004 onwards have xdrive , this means they usually only drive the rear wheels". The fact of the matter is they usually drive all four wheels.

[Cole]

Originally Posted by amacman

ok whatever . the explanation of how the system works is there in print for you , if you can`t get your head around it then believe what you want , it`s no big deal , but you are still trying to bullshit what i said so that is why i took pics for people to understand what i said . you are correct in what you say about the 40% to 60% split when it is utilising 4 wheel drive but as i am trying to explain there is much more to the X drive system than just that alone . it is still predominantly rear wheel drive . you can look up the word predominantly in the dictionary if it doesn`t make sense to you .

I am afraid I agree with Fraser here, 60:40 is not predominantly either way, predominantly would be 90:10. And in any event I don't believe that the xDrive X's ever feel rear wheel drive, which is, I think, part of the point you were trying to make. As soon as you push traction so that you would be able to notice if it is rear, or front, or four wheel drive the xDrive system will shift the torque split and move the power front or back and it will feel like a four wheel drive system. No doubt the xDrive is better than the older system, but I doubt you could tell the difference in normal driving. The only time it is important is at traction limiting conditions like snow, mud or sand.... or on a race track!

[amacman]

Riddle Me This Batman ,
the pre 2004 uses planetary gears in transfer case to distribute torque.
the post 2004 xdrive uses a clutch to distribute torque so at 50% front and 50% rear the clutch is fully engaged to front .
at 40% front and 60% rear there must be some slip in the clutch to control torque to the front.
how long can the clutch pack sustain this slip .

[Cole]

Originally Posted by amacman

Riddle Me This Batman ,
the pre 2004 uses planetary gears in transfer case to distribute torque.
the post 2004 xdrive uses a clutch to distribute torque so at 50% front and 50% rear the clutch is fully engaged to front .
at 40% front and 60% rear there must be some slip in the clutch to control torque to the front.
how long can the clutch pack sustain this slip .

For the life of the transmission if that is what it is designed to do...

Just because they call it a clutch it does not mean that it is the same design as the clutch on a manual transmission, which would wear out if habitually run only partially engaged. The clutch on a manual transmission is designed to run fully engaged most of the time and to not slip, the xDrive transfer clutch clearly is designed to slip most of the time.... Think of it more like the torque converter on a auto box.