I have the same problem with my 300SL. Have already replaced the K1, replaced fluid & filter, etc. and it did nothing at all. Here's my plan:

1. Make sure the modulator holds vacuum, and the little plastic cap isn't cracked (search the forum.. these are two common problems).

2. Run a can of Seafoam Trans Tune through. I've heard good things about this. http://www.seafoamsales.com/transTuneTech.htm

3. Drive the car hard for a bit

4. Drain the fluid and replace filter.

5. Fill with Mobil 1 ATF, including 1 can of Trans-X (also heard good stuff about this)

6. Test car. Hopefully fixed

7. Take car to shop to have transmission rebuilt.

What does 'minimally invasive' mean by the way.. Is it something that can be done with the pan off, or does it require transmission removal??

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'83 300SD 335,000km (207k) mi SOLD
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