My car holds off shifting until I reach 3000 rpm when first starting up and driving off. Are you reaching 3000 rpm before yours shifts? I don't think the delay has anything to do with "how far", rather, how quickly.

I am told my car needs a retard upshift dleay valve and the dealer wants to charge me $1200 to fix it. What do you think? Seems like you had the same problem a few years back.

Are they insane? I would simply take it to a trusted independent MB Shop.

Steve