I'm not sure that any data exists for "MTBF". . . .

There's data from the manufacturer for "changing" the part b/c its useful life is 'over'. But that's a lot different from MTBF.

For example, a Bosch O2 sensor is recommended for change at 60k miles. But, as we all know, many are still running them well in excess of the mileage.

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Regards . . . . JimF
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'94 S500 Cpe

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