i replaced my clutch a while ago, and drained the transmission in the process. i filled it with something other than the dealer recommended fluid, and i didn't use redline either. now i'm noticing a gear whine sound when i downshift. the question is, would the fluid type cause that, or did i put something together wrong? i'm sure i followed the manual right, except for the type of fluid...

 

What is "something other than the dealer recommended fluid"? Does it have the same specs as OEM fluid?