The transmission is not shifting to fourth gear. on 1993 Volkswagen Jetta

The car is a four speed automatic. When driving on the highway going about 62-65 mph the rpms are around 4k. The transmission shifts fine from 1 to 3 but going to 4th gear nothing it stays in 3rd gear. I did research and seen that this is a common problem but cant find a fix.

1 answer
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