drill works but the chuck wobbles a lot when it spins, is the shaft bent or something?

Diagnosis

The "wobble" or run-out experienced on the Ryobi ONE+ HP 18V Brushless Drill (PBLDD01B) is rarely caused by a bent motor shaft or a warped spindle. Because this is a brushless model, the motor is decoupled from the chuck via a planetary gear reduction system. For the shaft to be physically bent, the tool would typically have to suffer a catastrophic impact or a seized-bit event that would likely crack the outer plastic housing first. The most common root cause is "off-center seating." This occurs when a drill bit is inserted slightly skewed, or when debris—such as sawdust, metal swarf, or drywall dust—accumulates in the bottom of the chuck jaws. Even a tiny particle of grit can prevent the jaws from gripping the shank of the bit squarely, causing the bit to orbit the center axis as it spins. To confirm this, remove the bit entirely and spin the chuck at a low speed; if the chuck itself rotates smoothly without a visible "hop," the issue is the bit seating. If the chuck itself is wobbling, the issue is likely a worn-out bearing in the gear housing or a loose chuck assembly.

How to Fix It

Follow these steps to calibrate the chuck and eliminate the wobble:

1. Remove the current drill bit and set it aside. Open the chuck jaws to their maximum width by rotating the sleeve counter-clockwise.
2. Use a can of compressed air or a vacuum with a narrow nozzle to clear the interior of the three jaws. Pay close attention to the base of the jaws where debris often collects and prevents a flush fit.
3. Insert a high-quality, precision-ground drill bit. Ensure the bit is pushed firmly to the back of the chuck before tightening.
4. Tighten the chuck sleeve by hand until it is snug. Once hand-tight, give the sleeve an additional 1/4 to 1/2 turn to ensure the jaws have locked the bit's shank centered.
5. Set the drill to the lowest speed setting (Speed 1) and trigger the motor slowly. Observe the tip of the bit. If the wobble persists, swap the bit for a different brand to rule out a bent accessory.

If That Didn't Work

• Check for Chuck Slippage: If the wobble is present even with no bit inserted, the chuck may have become loosened from the spindle. While the PBLDD01B is a keyless system, the internal threading can occasionally slip. Try tightening the chuck assembly against the housing if there is visible play between the chuck body and the drill head.
• Inspect the Bit Shank: Many "wobble" issues are actually caused by the bit itself. Check your drill bit by rolling it across a flat table; if it doesn't roll in a perfectly straight line, the bit is warped and must be replaced. This is common with cheap, bulk-pack bits.
• Bearing Inspection: If you hear a grinding noise accompanying the wobble, the internal spindle bearing may have failed. This usually happens if the drill was used for heavy-duty mixing or side-loading. This requires a teardown of the gear housing to replace the needle bearings.
• Collet Cleaning: Use a small amount of WD-40 or a penetrating lubricant on a cotton swab to clean the internal threads of the chuck. If the jaws aren't moving symmetrically due to gunk, they will push the bit off-center.

Heads Up

• Avoid over-tightening the chuck with pliers; excessive force can strip the internal threads of the PBLDD01B's keyless mechanism, leading to permanent run-out.
• Never use the drill to "hammer" a bit into place; always use the sleeve to secure the bit to prevent damaging the spindle alignment.
• Regularly blow out the chuck with compressed air every 5-10 uses, especially when working with masonry or composite materials that produce fine, abrasive dust.
• Ensure you are using bits with shanks that match the chuck diameter perfectly; using a thin bit in a large chuck can sometimes lead to inconsistent gripping and increased wobble.