I bought this inpeccable s420, no warning lights, everything works, with 80K miles.
It does have a transmission problem.
all upshifts are fine,at any power setting.
But a 4 to 2 or 3 to 2 downshift is disastrous.
The engine revs up to high, and than slams into gear very very hard.
It makes no difference if you step on the gas a little, or a lot.
I read a MB service builletin about this, indicating problems with the front brake band (B1)

I did scan the transmission for codes, none. (use a snap on modus, with trans software).

Any feeback?

Thanks, henri.

That trans(722.6) doesn't have bands only clutch packs! A most common problem is a broken spring in the valve body. MB list price is $1.50, however dis-assembly of a valve body isn't a DIYer.

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Thanks MB dock, Does this broken sprinfg indeed cause this down shift problem, ?
I have a shop, and am certainly capable to pull a valve body, but will need some help finding the location of this specific spring.

Many thanks, Henri.