Someone already posted up a topic with pretty much the exact same question as me, but he had the s14 i believe, and i got an s13 (dont really know if that makes a huge difference or not). I just recently bought a 1989 s13, and im having trouble with the 3rd gear, and sometimes with reverse. When going from 1st to 2nd, and going from 3rd to 2nd or 4th is fine also, but when im going from 2nd to 3rd it grinds almost all the time, and when going from 4th to 3rd it pretty much does grind all the time. now the grinding isnt severe, but its really quite aggrivating. Anyway from what i could tell from the last topic, people were saying to bleed the transmission, and put Redline MT-90 in it.
i was just wondering if that's what i should do for my s13
Thanks
