In a message dated 9/27/2014 3:43:05 P.M. Eastern Daylight Time,
camping.elliott@GMAIL.COM writes:

I  remember that two, three months ago, someone posted here about a
cleaner or  restorative that was good for the crumbling brown auto
transmission lever  handle, then went on to extoll the stuff's amazing
ability to restore the  finish on just about anything plastic?

there is no fix.  just replace it with a black  one.