I would take it to a well recommended indy shop for an inspection and if they were not comfortable in also diagnosing the transmission also to a transmission shop that is familiar with BMW transmissions. Regards if there are symptoms of a problem or not that is the most critical part of preventing buyer's remorse when purchasing any used vehicle. Even if you are completely DIY capable get a second opinion.

There are usually several potential causes of the same engine and transmission symptoms. Without an in person diagnosis there is no reason to conclude the transmission is failing.

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