A floating tremolo unit allows guitarists to raise and drop the pitch of notes with the tremolo arm. As its name implies, the back end of a floating tremolo unit is raised slightly off the body of the guitar. The vast majority of Fender Stratocaster guitars come with a Fender vintage tremolo unit, which can be easily adjusted with screwdrivers. However, if these adjustments are made haphazardly, the guitar may not sound right and you run the risk of damaging the instrument.
Remove the plastic plate on the back of the Stratocaster. This plate is generally held in place with six Phillips-head screws
Examine the springs in the tremolo cavity. If there are three or fewer, you don't need to do anything. Skip ahead to Step 5.
Loosen the guitar strings until they become slack if there are more than three springs attached to the tremolo.
Remove the second and fourth springs if there are five of them in the tremolo cavity. Remove one of the middle springs if there are four. If the springs are difficult to remove, you can lessen the tension on them by loosening the two screws at the top of the tremolo springs. Tighten the strings (tune to standard tuning) once you have removed these springs.
Measure the height of the back of the bridge (the floating part). It should be around 3mm (1/8 inch) off the guitar body. If it is not that high, tighten the screws above the strings in the rear cavity of the Stratocaster. If it is too high, loosen these screws.
Adjust the six screws at the top of the bridge unit on the front of the guitar (beneath the strings) until this section of the bridge is 1.5mm (1/16 inch) above the guitar body. On most Stratocasters, these screws will need to be loosened.
Retune the strings and check the measurements again. Make any needed adjustments. Replace the plastic plate when you are done.
To avoid damaging your guitar, do not over-tighten any screws.