CTA Tools 1066 Crank Bolt Socket - 21mm, Counter-Weighted, 1/2" Drive for High Torque Pulley Damper Bolts

• The CTA Tools 1066 Crank Bolt Socket is a specialty tool for loosening high-torque crankshaft pulley or damper bolts with a 21 mm hex head. Its counter-weighted design reduces off-axis load and improves stability during heavy torque applications.
• Features:
  • Counter-weighted internal design — balances torque forces and reduces side load, improving socket stability under extreme loads
  • 89 mm overall length — provides reach into tight engine compartments while maintaining rigidity
  • 1/2-inch square drive compatibility — works with standard 1/2-in drive torque or impact tools
  • Black finish — likely protective coating for corrosion resistance and wear
  • Designed for 21 mm hex crank pulleys — used widely on GM, Ford, Chrysler, Dodge, Jeep, Mazda, and other applications that use 21 mm crank pulley bolts
• Specifications:
  • Manufacturer: CTA Manufacturing / CTA Tools
  • Part Number: 1066
  • Socket size (hex): 21 mm
  • Drive size: 1/2-inch square drive
  • Overall length (OAL): 89 mm
  • Design: Counter-weighted for high torque use
  • Finish: Black (protective coating)
  • Interchange: Lisle 77100
• The CTA Tools 1066 Crank Bolt Socket can also be referred to as CTA 21 mm crank bolt socket, counter-weighted crank pulley socket 1066, CTA 1066 1/2-in drive crank socket, harmonic damper bolt socket 21 mm, and specialized crank bolt removal socket.

 

The CTA 1066 is built for professional engine service, especially when removing tightly torqued harmonic balance or pulley bolts on engines using 21 mm crank bolt patterns. The counter-weighted design helps maintain alignment and reduce wear under severe stress.

 

Q: Why is the socket “counter-weighted”?
A: The counter-weighting helps offset torque reaction and reduces side thrustors during loosening, making the socket more stable under high loads and decreasing the risk of slippage or damaging the bolt head.

 

Q: What engine applications use this 21 mm socket?
A: It fits 21 mm hex crank pulley/damper bolts on various GM, Ford, Chrysler, Dodge, Jeep, and Mazda engines, among others that follow the 21 mm bolt standard.

 

Q: Can I use it with impact tools?
A: Yes — it is intended for use with 1/2-inch drive tools, including torque wrenches or impact guns, provided the tool and fastener ratings are respected. Always control torque and use proper techniques to avoid overtightening or tool failure.