I'm no expert on the tranny's but I've experienced a failure in the past on my E34 525i >100K miles. That cost me IRE£1100 for a tranny rebuild at that time.

The trans failsafe error will put the tranny in 3rd gear only to allow you get home - hence the sluggish performance when the error is active. The cause of the error can be many things from a simple sensor failure to a major mechanical issue. Let's hope that in your case the speed sensor replacement solves the problem.

If your car has been driven normally (not thrashed) and well looked after - the 139K miles should not be too much of a worry. For cars harshly driven - the tranny could be nearing the end of it's life at this mileage.

Regarding your comments above (leaving the SES without arranging a service and putting the standing start acceleration to the test) - If this is your routine practice then it will take it's toll on the car at some point.

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Cheers, Brian

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2001 X5 4.4i Sport
Black Sapphire, Hi Gloss Shadowline, Full Privacy Glass.
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