I had a 1985 300sd and the transmission would flair from 1st to 2nd. But only if I had it floored.
Well I soon backed off and gave my transmission a break until I could find a fix.
Did some research and found out there was a Mercedes fix for the flaring problem. Cost around $20. BUT you had to remove the valve body and put the kit in which had valves, springs, and it was a long time ago so I can't remember but I put the entire kit in. I also bought the corresponding Mercedes transmission book to make sure everything got put back together and torqued per specification. While at it I replaced the filter and fluid.
That fixed the flaring issue.
If you can't find a Mercedes fix for your problem then I would suggest a transmission shift kit.
I bought a superior K68908AS which is for 722.3/722.4 transmissions. I didn't use the kit because I bought the Mercedes kit. Of course I didn't find out about the Mercedes kit until I already had the superior kit.
Roddy

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