Hey I need help again..... So I hooked up the rear tank today and was listening under the vehicle and realized there a whining noise coming from in or around the transmission. the truck is an 86 f150 with the inline 6 and granny 4 speed manual. any helpful suggestions on what it could be would br greatly appreciated

 

Confirm the gear oil is full first. If it hasn't been service in a while change the oil. Gears whine as the start to wear and get shiney. The gear lash gets larger and creates the whine. If it's working fine a the fluids are OK, drive it. Anything short of a master rebuild will not stop the whine. Good luck