Originally Posted by
Clyde1820
Very similar derailleurs, that Deore and that Deore XT. Same essential specs:
Deore XT FD-T8000 3x10:
Compatible chain HG-X 10-speed;
Chain line (mm) 50; Chainstay angle (deg.) 63-66; Top gear teeth 48T; Total capacity 22T; Applicable top-mid tooth difference 12T
Deore FD-T6000 3x10:
Compatible chain HG-X 10-speed;
Chain line (mm) 50; Chainstay angle (deg.) 66-69; Top gear teeth 44T, 48T; Total capacity 22T; Applicable top-mid tooth difference 12T
These two examples aren't compatible because of the chainstay angle, but both derailleurs are available for both angle ranges.
Part numbers have the format : "xxx-L3" for 62-66° and "xxx-L6" for 66-69°.
Just make sure the new one matches the old. The range should be stamped somewhere into the current derailleur.