I had a friend of mine do the tranny fluid switch about 5 months ago and it seemed fine after I picked it up but recently, it seems the notchiness and 3rd gear grinding is back (when cold outside).

Question is, is there a color difference or something I can check to see if this guy actually changed my tranny fluid to Redline?

Thanks for the replies...

 

well its naturally red when you put it in....

and the stock nissan fluid is sort of yellow/brownish. I'm unsure of how the redline looks used though