How often should I get transmission flush on e350?
When did you have it changed last? If you never did, now would be a goo d time.
MB has a MUCH shorter recommended schedule than other manufacturers. Often every 40k or 50k miles whereas many others are at 100k. Regardless, at 150k you are way overdue. One sidenote: some people report that they waited so long (overdue) to do this service that when they did do it, other problems developed because the old 'tranny' could not handle the new fluid and filter. Maybe just an urban legend - but check with your mechanic.
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