BMW xDrive. Would you tick the option box?

[anonymous-user]

Nope. because i'm not a massive fanny........ ;-)


(my current 3er can put all it's power down 99.9999% of the time with just rwd, so why would i want to lug another 100kg around all year that dulls the handling, knocks the edge of the performance once moving, makes the car more difficult to steer. My suggestion, spend the money on LSD instead!)


(and once all the numpties who can't drive for toffee in the snow get 4wd BMWs instead of not being able to start moving, they will simply not be able to stop moving instead............)

[white_goodman]

EricE said:

I suppose it always depends on where you live, but with the M135i and M135i xDrive I would absolutely go with the AWD version. The RWD version without a LSD would be a real pain in winter here in Austria.
Mind you snow tires are mandatory here but what good is a 320 hp one-wheel drive car on a snowy mountain pass...

I think a lot of people still associate AWD in small cars with the old front heavy implementations with the old versions of Haldex and very "safe" calibrations (Audi). True rear biased AWD like xDrive is a wonderful thing and the newer Haldex (VAG MQB, A45) systems are almost as good now.

This is the last new BMW I really lusted over!



It has all the right ingredients that I associate with BMW:
Conservative but handsome styling;
Revvy NA straight six petrol (surely one of the best engines ever made)
RWD
Manual gearbox

I'm not sure why I've never owned one. Would love an E46 CS or CSL but just had a look at prices and they're more money than I expected for 10+ year old cars! However, a friend owned a "normal" E46 M3 and said it was too fast to enjoy on the road most of the time and promptly sold it and bought a 106 Rallye instead, which he says he prefers!

For some reason, the new M3/M4/M5 just doesn't seem to do it for me (haven't read any reviews on the new M3/M4 yet though)! If I was going to buy myself a new BMW, I quite like the look of the 435i/435d Gran Coupe, possibly with xdrive, as I currently live in Canada where the roads are snowy and icy for 50% of the year and being able to put the power down in those situations without the massive wheelspin that ensued under even modest throttle openings in my relatively modestly powered FWD car last winter. Conversely, on normal tyres, the Jeep we had just gripped and went without any drama. Sadly we don't have the Jeep any more but have a set of winter tyres on my wife's new FWD car, so will be interesting to see how effective they are this winter (never driven on winter tyres before).

Would xdrive be worth it in the UK? I'm not so sure but my Impreza was awesome in the snow on the few occassions that it snowed on "normal" tyres and no less fun for being AWD (but maybe a bit worse on fuel). It's good to hear the xdrive system is rear-biased and hasn't been detrimental to the dynamics from those that have driven one. I expected the usual tirade from the RWD lovers who haven't tried one but it's not RWD, so must be crap! Personally, I have least experience time-wise with RWD (although have owned 3 RWD vehicles) but have also owned AWD/4x4 and FWD vehicles and think that all three configurations can be brilliant if executed well. I didn't realise about the extra ride height though. Not necessarily a bad thing here but if it looks funny that might put me off! I wonder why? Do quattro Audis ride higher than FWD Audis? How does quattro compare to xdrive i.e. what's the torque split/balance? I've only driven the Haldex-type quattro (A3/Golf?) which works OK but feels a bit weird.
Just when you think the front wheels are going to spin as they would in the FWD version, the drive shuffles to the rear axle and rockets you forward but feels like a FWD most of the time. I would prefer a rear-biased system or the Subaru AWD system personally.

I'm torn between a new 435i/435d Gran Coupe and a lightly used A5 3.0 TDI quattro or S5 Sportback. quattro being a no-brainer in the case of the Audi!

[Zwolf]

Urban Sports said:

I'm pretty sure my next car will be a 330d M Sport, I wouldn't get the 335d because it's x drive only, they just don't seem to sit right.

Consider an ALPINA D3 then, more power still and available in RWD (with the further option of a mechanical LSD) and similar price to a speccy 335d.

In terms of "sitting right", ISTR that xDrive F3x models sit 10mm higher than RWD ones, whether M Sport or SE/Modern/Luxury trim.

I'd rather choose an xDrive BMW if I truly needed year round AWD traction than be forced by default to go the more traditional Audi route. That said, the larger engined petrol Volvos have all been AWD in recent years and an S80 V8 or T6 appeals hugely as a comfy, quick-ish and capable barge.

[EricE]

white_goodman said:

but if it looks funny that might put me off! I wonder why? Do quattro Audis ride higher than FWD Audis? How does quattro compare to xdrive i.e. what's the torque split/balance? I've only driven the Haldex-type quattro (A3/Golf?) which works OK but feels a bit weird.
Just when you think the front wheels are going to spin as they would in the FWD version, the drive shuffles to the rear axle and rockets you forward but feels like a FWD most of the time. I would prefer a rear-biased system or the Subaru AWD system personally.

I'm torn between a new 435i/435d Gran Coupe and a lightly used A5 3.0 TDI quattro or S5 Sportback. quattro being a no-brainer in the case of the Aud

All of the old VAG Haldex implementations generally put 100% torque on the front axle until some loss of traction occurs. From my understanding they were also relatively slow to react which is how that effect you mentioned occurs.

The newer Haldex gen 5 works a LOT faster and puts more torque on the the rear axle based on other factors like g-force, acceleration, etc. Thats why the calibration makes such a big difference (i.e. Golf R going sideways vs S3 having a tendency to understeer). Still, the torque is on the front axle under normal conditions.
See: https://www.youtube.com/watch?v=ZSkwYwgd3ZI

xDrive works in a very similar way to Haldex but it puts all torque on the rear axles by default which is why it feels so much sportier. It’s a RWD car most of the time until you need the additional traction.

Other Audis (A4 and up) use a torsen center differential which is a whole different thing all together.

The reason why Haldex doesn’t provide a full time 50:50 or 60:40 torque split is obviously fuel economy. A company here in Austria sells a modified Haldex controller for VAG cars with the old Haldex. It’s tweaked to always provide 50:50 torque so clearly that would be possible.

https://www.youtube.com/watch?v=FHa823iSFM4
(seems like they mixed up the top and bottom videos because the bottom one does not look anything like the normal FWD based understeery version)

[white_goodman]

EricE said:

All of the old VAG Haldex implementations generally put 100% torque on the front axle until some loss of traction occurs. From my understanding they were also relatively slow to react which is how that effect you mentioned occurs.

The newer Haldex gen 5 works a LOT faster and puts more torque on the the rear axle based on other factors like g-force, acceleration, etc. Thats why the calibration makes such a big difference (i.e. Golf R going sideways vs S3 having a tendency to understeer). Still, the torque is on the front axle under normal conditions.
See: https://www.youtube.com/watch?v=ZSkwYwgd3ZI

xDrive works in a very similar way to Haldex but it puts all torque on the rear axles by default which is why it feels so much sportier. It’s a RWD car most of the time until you need the additional traction.

Other Audis (A4 upwards) use a torsen center differential which is a while different thing all together.

The reason why Haldex doesn’t provide a full time 50:50 or 60:40 torque split is obviously fuel economy. A company here in Austria sells a modified Haldex controller for VAG cars with the old Haldex. It’s tweaked to always provide 50:50 torque so clearly that would be possible.

https://www.youtube.com/watch?v=FHa823iSFM4
(seems like they mixed up the top and bottom videos because the bottom one does not look anything like the normal FWD based understeery version)

Thanks for that. xdrive sounds a bit like the 4WD system in the Ferrari FF then, which can't be a bad thing! How does the non-Haldex quattro (torsen diff) system work then?

[EricE]

white_goodman said:

Thanks for that. xdrive sounds a bit like the 4WD system in the Ferrari FF then, which can't be a bad thing! How does the non-Haldex quattro (torsen diff) system work then?

I don’t really understand that well enough myself but unlike the clutch based system like the Haldex, the torsen system has a limited slip center differential that constantly provides 40% torque to the front and 60% to the rear. So true all wheel drive. When it detects slip on one of the axles, the diff gradually "locks" itself and tries to send more torque to the axle that has traction.

The Ferrari FF comparison is really accurate because it is also clutch based and rear biased. I never looked at it that way. The Aventador, Huracan and Veyron (!) also use a rear biased version Haldex.

I should also mention that the xDrive behaviour I mentioned above only applies to the 1 series. Larger BMWs probably also use different systems with center diffs and permanent 40:60 split.

[Diderot]

Yes I would indeed. XDrive m135i (why does the UK not get them?) would be stellar and my new (08 plate) 635d would spin its wheels far less for sure at 50 mph in the wet

[jamieduff1981]

No, because although not a driving god I'm not a hamfisted arse either and have successfully enjoyed RWD cars in all weathers in Scotland for many years.

Clearly my world is not the real world but since I spend almost all of my time in my own world I don't mind that my RWD cars will spin off the road in a ball of fire if I try to enjoy myself on a wet day if I should accidently cross dimensions and find myself in the real world of binary throttles and corner speeds limited by grip rather than sight lines.

[lord trumpton]

jamieduff1981 said:

No, because although not a driving god I'm not a hamfisted arse either and have successfully enjoyed RWD cars in all weathers in Scotland for many years.

Clearly my world is not the real world but since I spend almost all of my time in my own world I don't mind that my RWD cars will spin off the road in a ball of fire if I try to enjoy myself on a wet day if I should accidently cross dimensions and find myself in the real world of binary throttles and corner speeds limited by grip rather than sight lines.

Its not about safety or nannying, its more about being able to harness the full torque of the engine in the lower gears without the dsc kicking in or lighting the wheels up like a dousche.

All BMW engines are now Turbocharged and all that extra torque is harder to contain with just a set of rear wheels.

Try one - its not like you would imagine and theres no understeering like the regular AWD cars.

[jamieduff1981]

lord trumpton said:

jamieduff1981 said:

No, because although not a driving god I'm not a hamfisted arse either and have successfully enjoyed RWD cars in all weathers in Scotland for many years.

Clearly my world is not the real world but since I spend almost all of my time in my own world I don't mind that my RWD cars will spin off the road in a ball of fire if I try to enjoy myself on a wet day if I should accidently cross dimensions and find myself in the real world of binary throttles and corner speeds limited by grip rather than sight lines.

Its not about safety or nannying, its more about being able to harness the full torque of the engine in the lower gears without the dsc kicking in or lighting the wheels up like a dousche.

All BMW engines are now Turbocharged and all that extra torque is harder to contain with just a set of rear wheels.

Try one - its not like you would imagine and theres no understeering like the regular AWD cars.

Why? I can out drag 99% of other cars I come across out on the roads day to day wet or dry with 550ps and 500lbft of torque through the rear wheels anyway. Just how fast does someone need to go? I almost never NEED to pull in behind someone for a junction and only do because I'd look like a dick otherwise. Likewise, I've yet to opt out of an overtake in the wet even in the TVR let alone our electronic safety netted XF because of traction fears.

I used an F-Type V8S for a week in miserable weather for commuting this month. Not once did I find myself wishing I could go *EVEN* faster out of a corner in the wet.

It's simply unneccessary and more things to go wrong.

Edited by jamieduff1981 on Thursday 28th August 21:59

[redtwin]

No, if the time comes where I feel the need for 4WD I will chop the RWD BMW in for a Range Rover or some other proper 4X4.

[tomjol]

EricE said:

All of the old VAG Haldex implementations generally put 100% torque on the front axle until some loss of traction occurs. From my understanding they were also relatively slow to react which is how that effect you mentioned occurs.

The newer Haldex gen 5 works a LOT faster and puts more torque on the the rear axle based on other factors like g-force, acceleration, etc. Thats why the calibration makes such a big difference (i.e. Golf R going sideways vs S3 having a tendency to understeer). Still, the torque is on the front axle under normal conditions.
See: https://www.youtube.com/watch?v=ZSkwYwgd3ZI

<snip>

Without wishing to nit-pick, this is a common misconception. Even on the original TT, R32, S3 etc, loss of traction is not required for torque to be shuffled, and some torque is sent to the rear most of the time. Engine speed, pedal position etc are factored in, so you can learn to manipulate it to a degree.

This is not to say that "old Haldex" provides a thrilling dynamic experience, but it's better than it gets credit for.

ETA: As you say, third-party controllers are available, offering more "flexibility"

Edited by tomjol on Thursday 28th August 23:28

[Hughesie]

Had a 335dMsport xDrive tourer recently, epic off the line in launch mode. Far far far too quick for the roads as it just grips and grips.

[ORD]

white_goodman said:

This is the last new BMW I really lusted over!



It has all the right ingredients that I associate with BMW:
Conservative but handsome styling;
Revvy NA straight six petrol (surely one of the best engines ever made)
RWD
Manual gearbox

I'm not sure why I've never owned one. Would love an E46 CS or CSL but just had a look at prices and they're more money than I expected for 10+ year old cars! However, a friend owned a "normal" E46 M3 and said it was too fast to enjoy on the road most of the time and promptly sold it

What car is that? Handsome.

[white_goodman]

ORD said:

What car is that? Handsome.

E46 M3 CS

[scherzkeks]

EricE said:

All of the old VAG Haldex implementations generally put 100% torque on the front axle until some loss of traction occurs. From my understanding they were also relatively slow to react which is how that effect you mentioned occurs.

Gen 4 operates the same as Gen 5, and most VAG and Volvo products after 2008 had it.

Gen 2, which you speak of, was biased 85/15 in Audi implementations, and in most driving situations had a lot more tq on the rear axle than that. It winds back in cruising and parking.

EricE said:

The newer Haldex gen 5 works a LOT faster and puts more torque on the the rear axle based on other factors like g-force, acceleration, etc. Thats why the calibration makes such a big difference (i.e. Golf R going sideways vs S3 having a tendency to understeer). Still, the torque is on the front axle under normal conditions.
See: https://www.youtube.com/watch?v=ZSkwYwgd3ZI

The new Haldex starts off in 50/50 mode from a standstill, just like Gen. 4 did, that is why you perceive it as faster -- the torque is already there. It winds back once you get up to speed.

EricE said:

xDrive works in a very similar way to Haldex but it puts all torque on the rear axles by default which is why it feels so much sportier. It’s a RWD car most of the time until you need the additional traction.

No it isn't a RWD car by default. It puts 60 percent tq on the rear axle by default. The latest versions of the system do operate very much like Haldex cars though.

EricE said:

I

Other Audis (A4 and up) use a torsen center differential which is a whole different thing all together.

Not in the drive. Both systems do the same job but via different hardware. The Haldex is faster and tapers back tq as needed. On slip, the mech. systems max out with available torque bias at anywhere from 66-85 percent, depending on the system. The Haldex does up to 100 percent. The mech. system on the S4 offers a diff that spins up the outside rear wheel when cornering, which works quite well. I have no personal preference for either system, though the old B6/7 Torsens (RS4 not included) felt a bit agricultural and less dynamic than any 2WD or Haldex car.

[mclwanB]

Just as many people tick it as possible. Live in the country and need to be out in all weathers and would like one in a few years

[Driver101]

No I wouldn't go with xdrive.

For all the time it would be a real advantage, I'd rather have RWD for the rest of the time.

[Mr Tidy]

I think it all depends on what you want to use the car for.
Some years ago a work colleague went to the GP at Silverstone before it got rescheduled and managed to leave the quagmire car park unaided in his A4 Quattro when most others needed towing out, so if wet/mushy fields are on the agenda Xdrive may be useful.
For snow I doubt it helps much, winter tyres are a cheaper and more affective option - Autocar posted a video a while ago comparing 2 Skoda Yeti's, one on summer tyres with 4WD and one on winters with 2WD and the cornering and stopping abilities of the latter were so much better. After all every car had 4 wheel brakes but the ability to stop is determined by tyre grip.
That may explain why when it snowed a couple of years ago I drove my RWD 1 Series past a few Range Rover/X5 type vehicles fitted with bling wheels parked in fences and ditches.
You have to spec a car to suit your own needs rather than to suit the latest fad - I get so fed up with M-Sport and S-line owners moaning about the poor ride; you only have yourself to blame!

[DUMBO100]

A local BMW drove a 320d X Drive up indoor Ski Slope, which it tackled in seconds and with 5 people on board.. Very impressive