Extension ladder won't extend or lock

Symptoms

• Extension rope is jammed or won't pull the upper section up
• Rung locks don't engage over the rail when extended
• Sections extend but slip back down under weight
• Extension feels rough or sticky partway

Likely causes

• CommonExtension rope frayed, tangled, or jammed in the pulleyA worn or twisted rope can bind in the pulley wheel and stop the mechanism.
• CommonRung locks rusted or bentCorrosion or a bent lock hook prevents it from seating over the rail properly.
• PossibleGuide brackets misaligned or bentBent guides make the sections bind against each other while sliding.
• Less commonDirt or debris built up in the rail channelsGrit increases friction between the sliding sections.

What to do

1. Lay the ladder flat and inspect the extension rope for fraying, knots, or jamming in the pulley.
2. Check both rung locks for rust, bending, or debris preventing them from swinging freely over the rail.
3. Clean the rail channels and guide brackets with a brush, and apply a light silicone lubricant (not oil, which attracts grit) to moving parts.
4. Work the rope and locks by hand on the ground before attempting to raise the ladder, confirming smooth motion.
5. Replace a badly frayed rope or bent rung lock rather than continuing to force it, since a failed lock while in use can cause a fall.
6. Once repaired, test the full extension and locking action several times at ground level before climbing.
7. Store the ladder horizontally and out of the weather to slow future rust and rope wear.

Tools and parts

• Wire brush
• Silicone lubricant
• Replacement rope (if needed)

When to call a pro

If the ladder's rails or locks are bent from a fall or impact, replace the ladder rather than repairing it, since structural damage isn't safely fixable.

Safety