MB says "sealed for life." I suppose everyone can decide on their own definition of life, but for MB these days it seems to be "until the warranty runs out." After that they flatly refuse to help with anything. Opinions are all over the map on when to change the transmission fluid, and it is not cheap at around $200. I had mine changed at 75K, and a new transmission at 80K. Some people say 100K or 150K on the fluid. Then again, there are some 722.6 trannys out there with over 300K on the original fluid. Mine is staying as is unless it starts acting funny.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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