I recently had the transmission out of my '87 300SDL to replace the front pump due to installing it incorrectly previously and breaking the drive ears.

So I got it back together and have added 6 quarts of synthetic ATF.

The car shifts hard from 1st to 2nd and then... no third. It just stays stuck in 2nd.

Previously it shifted through the gears without issue.

I haven't had a chance to check everything over, what should I look for?

Sticky Bowden cable?

Could it simply be that I need more fluid?

The ATF was just below the low line but I was not able to drive it very long to warm it up. I know I have a little more to add but I wanted to get it warm to check it properly and the roads around me are 55mph so I need third gear.

Let me know what you think and thanks for the help!

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1987 300SDL 167k
1992 Volvo 740 140k
1990 Volvo 740 250k
1989 Volvo 240 269k

Anyone want to trade an old Volvo for an '87 300sdl?