new trans issue 4l60
the trans shifts fine 1-2 but when it goes to 3rd it only has the gear sometimes. feels like nuetral others, does not feel like slipping. it does great for hours sometimes then feels like it falls out of gear. I have asked on a few local sites and noone seems to know. could this just be a shift solynoid? or do you have any other ideas?
Thank you all in advance.


