2002 s80 new transmission filter and oil/ flush. Only picks up. Gears downhill.

[Breezy411]

Put new transmission filter and new oil and did a flush. It only goes in reverse. I went through all gears before driving quite a few times before driving after gear oil change. If going down hill it will pick up in 2nd gear then 3rd and drive. Will also pick up in 1st. But only starts in 2nd. Will pick up all other gears going down hill. What could be the problem and what should I check and do?

[MoVolvos]

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Fluid level can be tricky. After replacing the filter, gasket, adding a Transgo shift and them a complete flush on my 03 S80 T6 it drove sloppy with bump shift in second gear till I got the fluid level correct. Took quite a few test drives, double and triple checking the level till I read it and filled it correctly that it drove smoothly.

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