Diagnosis
The grinding noise you are hearing in your CRAFTSMAN V20 drill is typically caused by "gear clash," which occurs when the planetary gear sets are not fully aligned and locked into place. In these tools, the speed selector (the sliding switch on top) moves a shifting collar that engages different gear ratios. If the switch is left in a "halfway" position or moved while the motor is still coasting, the teeth of the gears rub against each other rather than interlocking, creating a harsh metallic grinding sound. This is often exacerbated by the accumulation of fine sawdust, drywall dust, or metal shavings inside the gear housing. These contaminants create friction and physical obstructions that prevent the selector switch from sliding fully into the detent (the locking notch). If you can feel a "mushy" sensation when sliding the switch, or if the noise persists even when the drill is stopped, it indicates that the internal lubricant has migrated or that debris is blocking the shift collar from seating properly.
How to Fix It
To resolve the grinding and ensure the gears are properly seated, follow these steps precisely:
- Remove the V20 battery pack immediately to ensure there is no accidental trigger pull during the process.
- Grasp the drill firmly and rotate the chuck by hand clockwise and counter-clockwise for three full rotations. This aligns the internal planetary gears and makes it easier for the selector to slide.
- Slide the speed selector switch firmly toward the chuck (Position 2 - High Speed). Do not stop halfway; push it until you feel a distinct "click" or snap into the detent.
- Pull the trigger for one second to confirm the gear is engaged and the noise has stopped.
- Repeat the process in reverse: rotate the chuck by hand, then slide the switch firmly away from the chuck (Position 1 - Low Speed/High Torque) until it locks.
- If the switch feels stiff, apply a small amount of compressed air to the gaps around the slider to blow out any trapped particulates that may be preventing a full engagement.
If That Didn't Work
- Internal Lubrication Refresh: If the grinding persists despite full engagement, the factory grease may have dried out or leaked. Remove the outer casing screws (usually 6-8 Torx screws) to access the gearbox. Clean out the old, contaminated grease using a lint-free cloth and apply a high-pressure lithium-based gear grease to the planetary gear assembly.
- Selector Switch Realignment: Check the plastic slider for cracks. If the external plastic switch is cracked, it may be moving the internal metal collar only partially. You can replace the slider assembly or, as a temporary fix, use a small flat-head screwdriver to manually push the internal collar into place.
- Gear Tooth Inspection: If you shifted gears while the drill was under heavy load (stalled), you may have "stripped" a tooth on the gear. Open the housing and inspect the teeth of the speed gears. If you see silver metal shavings (swarf) in the grease or missing teeth on the gear wheels, the gear set is physically damaged and requires a full replacement of the transmission assembly.
- Chuck Tensioning: Occasionally, a seized chuck can put lateral pressure on the spindle, making the gears harder to shift. Ensure the chuck is clear of debris and lubricate the spindle area with a drop of machine oil to reduce friction.
Heads Up
- Never attempt to shift speeds while the trigger is depressed; this is the fastest way to strip the gear teeth and permanently ruin the transmission.
- Avoid using the drill in extremely dusty environments without blowing out the vents periodically; dust ingress is the primary cause of "sticky" speed selectors.
- If you are using Position 1 for heavy-duty driving, ensure the drill is held perpendicular to the workpiece to prevent side-loading the gears, which can lead to premature wear.
- Always store your V20 tools in a dry environment to prevent the internal gear grease from separating or oxidizing.