What are the differences between different types of Fender® Guitar Tuning Machines?
Although it is possible to upgrade or change out tuning machines, you should know that they are not a simple drop in replacement; some modification to the headstock is required to make this change.
The diameter of the mounting hole on the headstock for our vintage style tuners is 11/32" (8.7mm), and the machines themselves have a .249" diameter string post. The mounting hole on the headstock for our die-cast tuning machines is 13/32" (10mm) with a .236 diameter string post. The modern tuning machines are obviously larger in diameter than the vintage tuners and consequently, the mounting holes will need to be enlarged to accept the new tuners. As this is not an easy project for a beginner, we would suggest that you only have a skilled luthier perform this modification for you.
Conversely, if you want to switch from the modern tuners to vintage style tuning machines, without having to fill and re-drill the mounting holes, you will need to purchase a set of conversion tuner bushings which allow an 11/32 string post to fit into a 13/32 diameter mounting hole without any filling and drilling. Fender does not produce or offer these conversion bushings, so you'll need to purchase them through an aftermarket parts supplier.