Citation:
Truss Rod
There are two different styles of truss rods found on Fender guitars and basses; the "Standard" truss rod, and the "Bi-flex" truss rod. Most Fender guitars and basses are equipped with a "Standard" truss rod (there are two types of "Standard" truss rod; one which adjusts at the heel of the neck, and one which adjusts at the headstock, but both operate on the same principle). The "Standard" truss rod can counteract concave curvature, for example: in a neck that has too much relief, by generating a force in the neck opposite to that caused by excessive string tension.
Fender also uses a unique "Bi-Flex" truss rod system on some instruments. Unlike the "Standard" truss rods, which can only correct a neck that is too concave (under-bowed), the "Bi-Flex" truss rod can compensate for either concave (under-bowed), or convex (over-bowed) curvature, by generating a force in either direction as needed for the correction.
Check your tuning. Install a capo at the 1st fret, depress the 6th string at the last fret.
With a feeler gauge, check the gap between the bottom of the string and the top of the 8th fret -- see the specification chart below for the proper gap.
Adjustment at headstock (Allen wrench): Sight down the edge of the fingerboard from behind the headstock, looking toward the body of the instrument. If neck is too concave (action too high), turn the truss rod nut clock-wise to remove excess relief. If the neck is too convex (strings too close to the fingerboard), turn the truss rod nut counter-clockwise to allow the string tension to pull more relief into the neck. Check your tuning, then recheck the gap with the feeler gauge and re-adjust as needed.
Adjustment at neck joint (Phillips screwdriver): Sight down the edge of the fingerboard from behind the body, looking up toward the headstock of the instrument. If the neck is too concave (action too high), turn the truss rod nut clock-wise to remove excess relief. If the neck is too convex (strings too close to the fingerboard), turn the truss rod nut counter-clockwise to allow the string tension to pull more relief into the neck. Check your tuning, then recheck the gap with the feeler gauge and re-adjust as needed.
Note: In either case, if you meet excessive resistance when adjusting the truss rod, your instrument needs constant adjustment, adjusting the truss rod has no effect on the neck, or you're simply not comfortable making this type of adjustment yourself, take your instrument to your local Authorized Fender Service Center.
Neck Radius
7.25" : .012" (0.3 mm)
9.5" to 12" : .010" (0.25 mm)
15" to 17" : .008" (0.2 mm)
