Thanks for your interest, guys. Looks like I'm the only one with this problem, so far.

For further information on my X5 sub-frame issue.......

The car was purchased new by me in January 2005. It has never been immersed in salt water or been used for beach driving.......although there is sometimes salt in the air due to ocean breezes.

The car has spent half it's life parked outside the garage on a flat concrete driveway, and is only used 2-3 times a week. The splash shield had never been off in 11 years.

The water definitely pools in the splash shield, around the sub-frame components.......just look at the rust stains on the top of the splash shield (which I couldn't remove).

And yes, as far as the repair goes.........it was much cheaper to do the 'cut and paste', as it was relatively easy to access.

A mechanic, after scratching his head, quoted 15-20 labour hours to do a complete swap. Bonnet off, support engine from top, engine protection plate off, steering out, suspension components, sway bar and struts off, engine mounts off, replace everything, fix anything that breaks in the process, new wheel alignment. It probably would have cost me over $2,000.

Anyway, now it's all good....the repair is neat and tidy and strong. The car also handles better, no vibration when braking at 80-100kph, and most of all, I have peace of mind that the control arm is not going to fall off and cause a serious accident.

Of course, in my case, all this could have been avoided if only the splash shield had drain holes in the relevant places.

Lesson learnt for me...........occasionally check the complete underside of the car, particularly under shields/covers etc.