anderlopez46 wrote

Es el sistema xdrive de bmw! Yo noto trabajar la transferencia en el suelo de los asientos traseros de mi bmw x6 30d 2022 en frío y no es ningún problema de caja de transferencia ni de los diferenciales. Comportamiento totalmente normal.

anderlopez46 wrote

El X5/X6 pesan muchísimo más y si llevan llanta 22 peor aun! Es totalmente normal, no te obsesiones! A mi también me pasa y coches recién sacados del concesionario lo mismo.
Yo cuando lo compré nuevo lo hacía, una pequeña resistencia en el volante y acelerador en giros muy cerrados y en frío, es el sistema xdrive! Totalmente normal!
Yo te hablo a velocidades de 5kms/h! Lo que tu describes no lo he sufrido nunca ni lo sufro! Es normal sentir el funcionamiento de la transmisión en el suelo del coche en la parte trasera, en frío, en giros muy cerrados, solo eso! Pero a velocidades normales no tengo esos síntomas!

starlights wrote

I wasn't able to feel anything as described above in your post Marty - I specifically looked for it. This is for X50i.

anderlopez46 wrote

Ahora me ha quedado claro! Muchas gracias! Yo lo único que siento es en el suelo de los asientos traseros el funcionamiento de la caja de transferencia en giros lentos en frío, como también el funcionamiento
de la misma en frío en el volante y acelerador. Ningún ruido raro y todo perfecto en caliente! Lo que te pasa a ti a mi no ma pasa! Perdón! No había entendido.

M a r t y wrote

Any pre LCI 40i's out there that want to do this test?

21X3M40 wrote

Marty, the vibration damper comes to mind on the lower control arms. Do you have those already?

yzhou2004 wrote

I do a lot of local drivings and honestly did not notice it. The only time I had similiar viberations on steering was due to a specific spot on a particular uneven road I drove through almost everyday.

But I will find some time tomorrow to do some testing if i can.

Go to 30mph and let go gas. coast to 25mph, slightly press gas to maintain 25mph without transimisssion shift up. Did I get it right?

M a r t y wrote

Yup, you got it, thanks! Since you're not used to it or tuned into it, you may need a number of trials to identify if its happening. The trick is to get the speed just right without causing the tranny to shift, which then changes the rpm and puts you on a different place on the torque curve.

yzhou2004 wrote

Was your viberations strong and high frequent as lane change warning? Or more subtle and uneven frequecies?

M a r t y wrote

At the right speed/rpm, the vibration is constant and medium strong, felt only at the steering wheel. You could compare it to the very mild setting for the lane change warning but at a higher frequency. You may not detect it if the road you're on is bumpy, rough, etc cause there's so much suspension working on roads like that.

yzhou2004 wrote

Just did a few more trials today. The road is by no means bumpy. Still did not notice the constant vibrations at range of 25-35 miles at 1200-1500RPM without shift changes. I occasionally feel viberations from run flat tires though but it is not constant.

DrAzazeign wrote

I experience the same symptoms with my 2023 (pre LCI) x5. Did you manage to pin point the exact cause?

Zumich wrote

Hi,I experience something like this.2025 x40i.When you speed up to 30-35 mph,let off and press gas slightly I feel small vibration over steering wheel.I think that the transmission is just on upper gear at this case and the torque band is not optimal.Try to push down gas gently,so the trans shift down 1 gear and see if vibration disappear