so i just had my transmission rebuilt not too long ago and i red up on the orgs forum and saw someone had posted a thread about about royal purple syn 75w-90 manualtranny oil but noone responded to him has anyone used this because thats what i had put in and so far its just like before . a bit notchy at first but it loosens up after a while of driving, im only asking because if its gonna screw me later id rather dump it and refill

 

If it's GL-5 rated, that could be the source of your issue.

 

im using royal purple synchromax manual transmission fluid and its great man smooooooth shifting

 

been using it for years in my track car with a quart of Redline Ultralightweight Shockproof mixed in. tranny is still surviving, so that's good news.