The brief
The X4 came in for its steering tie rods. On some of the older X4s the tie rods of the earlier design configuration are known to weaken over time, the subject of a BMW safety action, and it's exactly the kind of thing worth checking and sorting rather than leaving to chance. He brought it in for the inspection and the work. The tie rods are the links that connect the steering rack to the front wheels, so when you turn the wheel they turn the wheels. They have ball joints at each end, and if a tie rod weakens or its joints develop play the steering goes vague, you get a knock over bumps, and the front tyres can wear unevenly, and in the worst case a failed tie rod loses control of that wheel's steering. So when they're flagged, you replace them and reset the alignment.
The diagnosis
On the lift the steering and the tie rods were checked. The earlier-design tie rods were the items in question, and with the steering loaded there was the play and the condition you'd expect of the configuration that gets flagged. The rest of the steering and suspension checked out. That's a tie rod replacement, both sides done together with the updated parts, then a four-wheel alignment to set the geometry right.
The work
Both tie rods were unbolted and removed, and new genuine BMW-spec tie rods of the current design fitted, the ball joints torqued to the manual figures and seated properly. With both sides back together the car went on the alignment rig and the front geometry, toe in particular, was set to BMW's specification so the steering tracks true and the tyres wear evenly. A road test confirmed the steering was tight and precise, no knock over bumps, the car tracking straight.
The outcome
Tight, precise steering, no knock over bumps, the car tracking straight, and the alignment set so the front tyres wear evenly. The X4 went home with the steering sorted. A weakening tie rod is the kind of part you want renewed before it gives trouble, so changing both with the updated design and resetting the alignment put the steering back where it should be, with peace of mind.