I drive 120miles a day & after a recent trans rebuild the shifter will fall out of gear 2 times a day & only on right turns @ 50-75mph.

The amount of shift travel seems to be the same for 5th or 4th. I was thinking cable not adjusted for fwd/rev travel.

Also, I have a billet pro shop short shifter.

Any ideas?

 

The first thing I would do is check the adjustment on the cable

 

How do I do that? I assume the up & down cable right?