Mercedes 1982 300D Turbo... 161000+(?)

My 2nd post! While attending a tech session last week I overheard mention of a mileage counter that is located in the transmission of Mercedes deisels. This was not related to the odometer or instruments. TRUE or URBAN MYTH? I'd love to know because I have just acquiered my 1982 300D Turbo and the mileage counter was stopped at 1610000 and would like to find out the "true" mileage. (I now have it working again thanks to info I learned on your board!)

Thanks for a great board.