XSeries-forum

Is the rear portion of the sunroof meant to slide back when you open the sunroof fully? If I open it to tilt position then front and rear glass tilts so I think I have a fully working sunroof at the moment.

Pretty sure it does no sliding, the front tucks under the rear. They both tilt also with the sunblind across when you tilt it should part in the middle with a mesh strip

That's right. One push upwards tilts both glass bits and the cover splits open with the mesh in the middle

Sounds normal, or at least exactly what mine used to do. One push to the rear moved the roof back to its first stop, two pushes all the way back. I can't remember what the rear section did in that case though.

When the front panel slides back you also get an anti-draft device popping up too. If you ever get onto a test track you will find the anti-draft device auto lowers at speeds in excess of 110mph.

Being a Fleet Manager in my previous job gave me access to Millbrook once a year. I did take an X5 around the oval a few times, and at speeds around 110mph and noted the device retracting. I miss that track access, although I do still get invites every year in June. All sorts of manufacturers were there and all the tracks except the 'Mile' were open - it was the Car Park. You do have to be a Business Fleet Manager to attend though, and I don't know if BMW attend anymore.

I do remember being aboard a Police marked up Skoda Octavia vRS and being driven by a test driver when he flashed an Astra Turbo VRX 'out of the way' at more than 155mph in Lane 5 whilst 4-up though..... . We passed it with ease, and the faces of the passengers were a picture, as if they were all saying "but that's a Skoda and it left us for dust!" We were only allowed to use Lane 5 if accompanied by a qualified test driver. Mere mortals could use up to Lane 4 as long as we didn't exceed 110mph....ish...