How many miles on your X5 and do you know what suspension work has been done in the past? Yes, you should replace the tie rod ends as part of rebuilding the front suspensions if they have the same miles on them as the rest of the suspension. Generally, when a vibration only occurs in a particular speed range it is a tire out of balance. In your case since it is only on the left side in a turn at a particular speed range it doesn't sound like a tire issue. I suggest looking over the right suspension where the weight is transferred when turning left. Even though it doesn't sound like an out of balance issue or a wheel that is not true it is the easiest 'potential' problem to eliminate. Before you do that I suggest you check the tie rods and the torque on the suspension components already replaced. Also check the sway bar links as they have about the same life as the rest of the suspension.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas