[Neusser]

Originally Posted by g21

in normal driving at constant speed going straight 100% rwd. front wheels activated on demand (actively by computer before the car slips) - eg accelerating, turning, driving on snow, etc

my m340i goes sideways driving at a constant 55mph on loose tarmac! but the dealer has found the front diff is whining, so i'm not sure it that's got anything to do with it.

My 540 steps out on exit ramps when I run the BMW tire pressures. When I run lower pressures in line with the weight of the car and the tire, this happens less.

X-drive is setup for fun. This is particularly noticible in the snow. An Audi would plod along like a shopping cart, but the 5er always feel like it is on the verge of stepping out.

Was in Switzerland a few weeks ago, with snow on Alpine roads--that was interesting.

[G30M]

Originally Posted by NGT2

Anyone know if the xDrive system works differently in my M550 than my X7 40i?

We’re supposed to get some snow (not a lot) and I’ve got to go somewhere later. Just curious if the X7 is better on snow than the M550. Both have AS run flats. Ground clearance won’t matter.

i don't know that it does (work different). these cars are heavily RWD biased when all is well (i have an app called bimmergeeks protool that shows 99% of the time it is pure RWD), yet when you drive on snow (i have NOT), people report that it drives fine on any of these cars on all season tires

i'd be cautious on either car as neither has snow tires. i'd say both AWD systems work the same way. i'd say the car with higher profile tires (the 2nd number on the tire sidewall eg 275-45-20 would be better than 275-35-20) would give better grip.

[HerkHealer]

Really interesting topic. Learned quite a bit about X drive on this one!

In my Telluride, there's a digital display on the dash that shows the amount of torque going to each wheel during its AWD functions. It's pretty cool and you can see exactly what's going on in real time.

[Qsilver7]

Originally Posted by HerkHealer

In my Telluride, there's a digital display on the dash that shows the amount of torque going to each wheel during its AWD functions. It's pretty cool and you can see exactly what's going on in real time.

Hmmm...you raise a good point. I think some xDrive models have a screen that shows something similar. I'm not sure if it is available on the sedans...but the older versions of iDrive used to have a screen that gave info on the SUV's xDrive system if you have DHP.


This is from ID4: