[antzcrashing]

Originally Posted by Laros1988

So.. improved fuel economy: myth or truth? It has been mentioned many times here (and also asked about..). Is there someone that measured fuel consumption before and after turning it off via the app?

I would doubt that it would help fuel econ because you are always just driving one wheel (either allowed to be any ie awd or allowed to be rear) and the software doesnt change the fact that the car has the additional and heavier awd drive components for the front. If anything I would expect it to be negligible at best if driving the rear wheels is more efficient because you are resisting the corning friction/forces less. But I will let others weigh in with data or counterpoints

[FaRKle!]

Originally Posted by Laros1988

So.. improved fuel economy: myth or truth? It has been mentioned many times here (and also asked about..). Is there someone that measured fuel consumption before and after turning it off via the app?

Complete myth. I record every fill up and when I averaged the RWD tanks vs AWD tanks the value was the exact same to the second decimal point (I was surprised by that).

[Skyhigh]

Physics would be invalidated as a science if it was not a myth

[chowser51]

Myth for me. Fuel economy didn’t change one way or the other for me.

[T0NE*F32]

Didn't really get a definitive answer to this but are there any concerns running xdelete long term?

[Skyhigh]

Originally Posted by T0NE*F32

Didn't really get a definitive answer to this but are there any concerns running xdelete long term?

By the time you find that answer for the COVID vaccines, we will know for xDelete for the F-series as well
Both are too new to tell.

[T0NE*F32]

Yea man I hear ya.. been wanting to give it a try but not sure if Im sold on it yet. It would be nice to be able to switch it on for winters and off for summers (as long as there's no issues).

I run staggered during summers but there's always a thought in back of my mind about the strain on transfer case.

[Logicoeur]

Originally Posted by T0NE*F32

Yea man I hear ya.. been wanting to give it a try but not sure if Im sold on it yet. It would be nice to be able to switch it on for winters and off for summers (as long as there's no issues).

I run staggered during summers but there's always a thought in back of my mind about the strain on transfer case.

Still no issues here in 2 years of daily use for winter/summer with dedicated tires.

[opinion914]

Mine has been prematurely letting the traction control kick in. Prematurely like when I'm at partial throttle and the tires are NOWHERE near breaking loose. According to Xdelete the solution is to manually turn off DSC or have my iStep updated. No idea about having iStep updated but it's a bit of a bummer to have the power cut for no reason. Main reason for me for having Xdelete was the potential increase in lifespan of the TransferCase but now I'm feeling it's a bit of a wash with the car going limp so frequently.
Anyone know what's involved with an iStep update?

[SethRed]

Originally Posted by opinion914

Mine has been prematurely letting the traction control kick in. Prematurely like when I'm at partial throttle and the tires are NOWHERE near breaking loose. According to Xdelete the solution is to manually turn off DSC or have my iStep updated. No idea about having iStep updated but it's a bit of a bummer to have the power cut for no reason. Main reason for me for having Xdelete was the potential increase in lifespan of the TransferCase but now I'm feeling it's a bit of a wash with the car going limp so frequently.
Anyone know what's involved with an iStep update?

Mine is doing this same thing. I actually noticed a stutter before getting the app. I was worried it was the Tcase going out. Got the app in an attempt to bypass the Tcase. Still get the stutter, but now the traction control light flashes. Turn off DSC and it goes away. After a little research, I'm thinking it might be a wheel speed sensor.

[E91Noob]

Originally Posted by fantanas

You can do it from esys.

"You can just change with ESYS module DSC > 3000 > C_Funktion_LaengsMomentVerteilung_aktiv_e > aktiv to nicht_aktiv
After you code this you will have RWD car WITH traction control, which can be turned off"

The traction light will stay on, but you will have a RWD car.

Is this the same module as on an e90-series car?

[RBT-Tuning]

Originally Posted by E91Noob

Is this the same module as on an e90-series car?

No, and the post you quoted is complete nonsense anyway. Sure you can code the DSC to be in RWD mode, but then the LMV (xDrive unit) and all units relying on signals from it will go to limp.

[fantanas]

Originally Posted by RBT-Tuning

No, and the post you quoted is complete nonsense anyway. Sure you can code the DSC to be in RWD mode, but then the LMV (xDrive unit) and all units relying on signals from it will go to limp.

I am not sure that this is true. I have tested it and it was working fine. It was my test before I got xDelete, just to see how it was. Definitely the xDelete is the way to go, but for a one off test that works.

[matrixen4]

Hey!
New member. I spent almost 3 hours reading through this whole thread yesterday, top to bottom. Thank you for the valuable information. I was gonna leave it at that, but i must say i kept getting irritated by some of the topics on and off in this thread. I would like to adress one particular one.

Many people here argue "if you want RWD then get RWD and not xdrive". How hard is it to understand. Winter sucks, xdrive is good during winter. But also slidey slidey sideways is fun as hell, and through xDelete we can get the best out of two worlds?

So. The reason for my following this thread was to get an understanding of whether the whole xDelete business is safe, and will not destroy the car. I understand now that it disengages the front clutch, meaning the cars 4wd will theoretically last longer, since it will be disengaged at times. Fine.

chowser51 Hey. You promised a few posts back in this thread to check back after using it for an extended period of time. Would really like to hear your experiences, any troubles at all with your car? Of course any other opinions on longevity / general problems (by anyone on here) due to xDelete are kindly appreciated!

Btw, im in the market for a m235i xdrive, and this would be my research

Again, thanks to all for a very entertaining read!

[johnung]

Originally Posted by FaRKle!

Complete myth. I record every fill up and when I averaged the RWD tanks vs AWD tanks the value was the exact same to the second decimal point (I was surprised by that).

Older post but this may add to the discussion:

I recall reading a lot of 1980's/90's articles about Audi's AWD system. Although there is a physics argument as to why gas mileage might be less when the engine drives four wheels instead of two, but that isn't the largest factor. Audi said that the biggest mileage factor was the added weight from the extra components needed to drive two extra wheels. Back then I would assume the weight was higher than today's AWD components.

Of course with xDelete there is no weight advantage because the front drive is turned off, but the weight of those components is still being carried around.

Hope this helps!

[Jarda_V]

Hi, I am considering xDelete installation on my BMW 435xd. There is engine + xHP tuning. About 360PS and 720Nm. I am a little bit worried about the output shaft from VTG. In the case of RWD setup. Most probably BMW engineers considering that torque will be split between from and rear wheels. Rear wheel drive is in OEM set up in the situation of not maximum torque. Is it OK for the output shaft?
And the second question is about clutch in SPORT or Snow mode. Documentation is describing that in that nodes there is less torque on the front wheels. That means that clutches discs will be more in sliding condition. What about the clutch's durability in that case? Thank you
Jaroslav

[RBT-Tuning]

Originally Posted by Jarda_V

Hi, I am considering xDelete installation on my BMW 435xd. There is engine + xHP tuning. About 360PS and 720Nm. I am a little bit worried about the output shaft from VTG. In the case of RWD setup. Most probably BMW engineers considering that torque will be split between from and rear wheels. Rear wheel drive is in OEM set up in the situation of not maximum torque. Is it OK for the output shaft?
And the second question is about clutch in SPORT or Snow mode. Documentation is describing that in that nodes there is less torque on the front wheels. That means that clutches discs will be more in sliding condition. What about the clutch's durability in that case? Thank you
Jaroslav

Sport and Snow modes are not available for F-Series, for exactly that reason. The clutch-pack is just too weak for those modes. (E-Series had bigger pack)

The driveshafts take a beating from abuse...not really from engine torque. So drifting around, wheel-hopping etc. can kill them...just like in any car. The induced torque through shock-loads is much higher, than anything the engine can produce. (RWD and AWD have same output shafts at the rear)

[Jarda_V]

Originally Posted by RBT-Tuning

Sport and Snow modes are not available for F-Series, for exactly that reason. The clutch-pack is just too weak for those modes. (E-Series had bigger pack)

The driveshafts take a beating from abuse...not really from engine torque. So drifting around, wheel-hopping etc. can kill them...just like in any car. The induced torque through shock-loads is much higher, than anything the engine can produce. (RWD and AWD have same output shafts at the rear)

Thank you. The license was ordered.
Jaroslav

[johnung]

Originally Posted by Laros1988

So.. improved fuel economy: myth or truth? It has been mentioned many times here (and also asked about..). Is there someone that measured fuel consumption before and after turning it off via the app?

The idea that AWD has worse fuel economy than RWD actually originates from Audi testing in the 80's/90's. Audi stated a few conclusions:

1) AWD drive is more efficient than 2WD because it eliminates the extra energy needed to push or pull the undriven wheels.

2) AWD has slightly worse fuel economy, but the reason is because of the weight of the additional AWD components which at that time weighed over 200lbs.

So engaging xDelete to turn off the front wheels of an XDrive car isn't going to gain any fuel economy because the car is still carrying around the extra weight of the XDrive components (which I would also assume weigh less than the Audi AWD components of decades ago.)

[Alarbus]

Also if you turn off xdrive and make it RWD it's a lot more fun to hammer in the corners and you lose mileage there. Speaking from a few summers of experience now.

It's convenient though, I can keep it awd in the winter and make it a bit more fun in the summer! That said, RWD on all seasons is total ass, you need some decent summers / high performance tires so the rears don't lose grip every five seconds.

[Skyhigh]

The concept of driving all-season tires in this century is beyond me. Irrespective of whether RWD or AWD.
People in Europe forgot what all-season tires are about 20 years ago. They were popular in the 90s. Later found to be simply the worst of both worlds.

[M27]

Hi everyone,

I have read posts above looking for any experience similar to mine but found nothing. So here is the case.

My car is the F32 435ix 8AT 2014.

I have flashed the xDelete using the android phone and the cable. Worked well at first attempt.
Switched to RWD mode. Also at first attempt.

Driving in RWD I have the noise coming from the transfer box.
The noise is like when gears are not fully engaging.
I hear it only when I'm accelerating at approx half throttle or more and only at the initial stage of acceleration. So it is heard clearly at first 1-2 seconds, depending on where is the pedal and how fast I'm pressing it down.
Less throttle - no noise.
Flat out - no noise (or I just don't hear it as engine is loud, or it is too short to notice).
Constant throttle - no noise.
Speed, gear and DTC mode do not make any difference.
It is same noise when accelerating, for example, in 2nd gear in town and in 5th on the highway.

I have verified that the noise is generated by xDelete in RWD mode. I switched the car back to AWD and the noise disappeared. Switched again to RWD and the noise came back.

Has anyone experienced this? Any ideas what makes the noise and why?

RBT-Tuning your comment would be much appreciated.

Thank you,
M27

P.S.: a pleasure for me to finally join Bimmerpost, after years of reading the topics. Let's talk ;)