yes they do if u leave them out u eventually break down the metal screw inside and cause damage to the shift linkage, or the screw just comes undone and u no longer can shift while driving. not fun, yah its a pita, trying to lay under the car, barly able to move while fumbling with the outter and inner peice while trying to hold it all together, and putting a screw thru it all with ur other hand while having gunk fall all over ur face, i did it a week ago when i put in a new engine, i hate the little stuff like that, always the biggest pita.