Torque converter Noise at lowish revs

[X5Sport]

Well at least you now know the labels have gone walkies.  You may be able to get replacements from BMW?  The part is this if you wanted to get one....

kkx5 - That doesn't seem to match the BMW University training document for the ATC500 unit fitted to the E53.  That describes 100% torque being shifted to the front if the rear is on ice as an example.  I'll need to re read it again.  ???

Getting back to the OPs issue, and there is obviously no simple way of forcing the system to front only without probably intervening with the on board electronics via a GT1 or similar Dealer system.

Pulling the fuse will just disconnect the front drive, not 'prove' the problem is the transfer box as it won't be properly under load (60/40 split) and in 'normal' mode.

Chances are it's the wrong sized front tyres, but pulling the fuse may help in some way.

Richard

[kkx5]

No matter what bmw says, there is no way to transfer 100% to the front There is no electrical way via bmw ista,inpa or any, to force to the front only couse front is driven by rear.  You can shift 100% of torq to the front and vise versa, but not the power, the speen. Disconnecting will prove the noise is coming from transfer.

[X5Sport]

I believe you....it's the engineer in me being curious 

R

[X5MO]

Okay guys, just had the front tyres put on, hey presto noise gone completely.

I went to a trusted BMW master technician 20 years experience who diagnosed early torque converter failure. Priced the repair at £2,500 and advised that I should sell the car.
I would never knowingly sell a car to another person that had a fault on it. Turned to family member and got the job done £250 TC reconditioned they said it wasnt bad at all. £150 atf 9 litres. £240 labour.
Grand total £640.00
After all that it turns out the fault was that I put 275 45 20 front tyres on instead of 275 40 20 and as a result of the 5mm height difference It cost me the above amount and could have cost £2,500.00.

I didn't ever imagine the tyres could be an issue and it even fooled my mechanic

I hope this post helps others and a special thank you to Richard and KKx5 for their input and support

Best regards

MO 

[kkx5]

:drunk:

[X5MO]

[quote="kkx5"]
:drunk:
[/quote]


kk
You wouldn't believe how great I feel, you dont realise how it affects you and then the joy of having a car that works and does what it should . Bliss

[X5Sport]

Glad it was a simple fix.  These cars are very sensitive to tyre sizes.

Richard

[X5MO]

[quote="X5Sport"]
Glad it was a simple fix.  These cars are very sensitive to tyre sizes.

Richard
[/quote]

Thanks, you can say that again Richard.  You live and learn mate