Originally Posted by workingonit

Thanks for the info. I can guarantee that those bolts have been tightened to 3-4 times the 45 ft-lbs (as were the lug bolts on the wheels I removed awhile back). I'm a long-time shadetree mechanic, but was a grad of a GM tech school, so I know when and where to use proper torque; obviously, my engineer friend skipped using his torque wrench, and instead used his whang-bang-super impact on those bolts!

If I need to remove the "stiffener plate", I will replace those over-tightened ones with new 12.9 grade replacements, properly torqued to specs. If BMW deems it a neccessary piece to maintain chassis rigidity, then I shall respect their judgement.

I may have to soak those bolts with PB blaster or WD-40 for a week in advance of removal, and use my best breaker bar (and another hand under the car with a box-end wrench) to actually free the bolts, but is there a problem re-assembling it, as it might be under stress?

As the oil has just been changed, and all the suspension components nearby (and the tranny and driveline parts refreshed in the last 3 years/2000 miles), I'll probably not have to do anything there for a year, so I'll file this info in my growing X5 compendium.