DEWALT 20V MAX XR 3/4 Inch Cordless Impact Wrench DCF964B User Manual

1. Introduction

This manual provides essential instructions for the safe operation, maintenance, and troubleshooting of your DEWALT 20V MAX XR 3/4 Inch Cordless Impact Wrench, model DCF964B. Please read this manual thoroughly before using the tool to ensure proper function and to prevent injury. Keep this manual for future reference.

Figure 1: DEWALT 20V MAX XR 3/4 Inch Cordless Impact Wrench (DCF964B)

The DEWALT DCF964B is a high-performance cordless impact wrench designed for heavy-duty fastening applications. It features a brushless motor, 3/4 inch hog ring anvil, multiple speed settings, and PRECISION WRENCH mode for enhanced control.

2. General Safety Information

Always follow basic safety precautions when using power tools to reduce the risk of fire, electric shock, and personal injury.

• Read all instructions: Familiarize yourself with the tool's operation and safety guidelines.
• Wear eye protection: Always wear safety goggles or safety glasses with side shields.
• Wear hearing protection: Prolonged exposure to noise from power tools can cause hearing damage.
• Dress properly: Do not wear loose clothing or jewelry. Keep hair, clothing, and gloves away from moving parts.
• Secure workpiece: Always clamp or otherwise secure the workpiece to prevent movement during operation.
• Maintain a firm grip: Hold the tool securely with both hands to control torque reaction.
• Use correct accessories: Only use impact-rated sockets and accessories designed for impact wrenches.
• Keep work area clean: Cluttered areas invite accidents.
• Do not operate in explosive atmospheres: Power tools create sparks which may ignite dust or fumes.
• Store idle tools: When not in use, tools should be stored in a dry, high, or locked-up place, out of reach of children.
• Disconnect battery: Always remove the battery pack before making any adjustments, changing accessories, or storing the tool.

3. Product Overview

The following diagram identifies the key components of your DEWALT DCF964B Impact Wrench.

Figure 2: Key Components of the DCF964B Impact Wrench

1. 3/4 inch Hog Ring Anvil with Thru-Hole: For quick and secure socket changes.
2. Brushless Motor: Provides increased efficiency and longer tool life.
3. Ergonomic Grip Design: Enhances user comfort and control.
4. Variable Speed Trigger: Allows for precise speed control based on application.
5. 4-Mode Push Button Switch (3 Speeds and PRECISION WRENCH Mode): Selects desired speed and specialized fastening mode.
6. LED Work Light: Illuminates the work area.
7. Battery Interface: For attaching 20V MAX* XR batteries (sold separately).
8. Tool Connect™ Chip-Ready: For advanced tool tracking and management (DCE042 sold separately).

4. Setup

4.1 Battery Installation and Removal

The DCF964B operates with DEWALT 20V MAX* XR batteries (sold separately). Ensure the battery is fully charged before use.

• To Install: Align the battery pack with the tool's battery port and slide it in until it clicks securely into place.
• To Remove: Press the battery release button (usually located on the front or sides of the battery pack) and pull the battery pack out of the tool.

4.2 Attaching and Removing Sockets

The 3/4 inch hog ring anvil allows for quick and secure socket attachment.

• To Attach: Push the desired 3/4 inch impact-rated socket firmly onto the anvil until the hog ring engages the socket, holding it securely.
• To Remove: Pull the socket firmly off the anvil. The hog ring design provides retention while allowing for relatively easy removal.

Note: Always use impact-rated sockets. Standard chrome sockets are not designed for impact use and may shatter, causing injury.

5. Operating Instructions

5.1 Powering On/Off and Variable Speed Trigger

To turn the tool ON, depress the variable speed trigger. To turn the tool OFF, release the trigger. The tool's speed is controlled by the amount of trigger depression; the more the trigger is pressed, the higher the speed.

5.2 Forward/Reverse Control

The forward/reverse control button is located above the trigger. Push the button to the left for forward rotation (tightening) and to the right for reverse rotation (loosening). Center position locks the trigger to prevent accidental startup.

5.3 Speed Settings and PRECISION WRENCH Mode

The DCF964B features a 4-mode push button switch to select between three speed settings and the specialized PRECISION WRENCH mode. These settings allow you to optimize the tool's performance for various applications.

Figure 3: Speed and Mode Selector with LED Work Light

• Speed 1 (Low): Provides lower torque and speed for delicate applications or when starting fasteners.
• Speed 2 (Medium): Balanced speed and torque for general fastening tasks.
• Speed 3 (High): Delivers maximum torque and speed for heavy-duty applications, such as breaking loose stubborn fasteners.
• PRECISION WRENCH Mode: This mode is designed to help prevent overtightening and fastener run-off.
  • In forward, the tool will pause before impacting to prevent overtightening.
  • In reverse, the tool will reduce speed once the fastener is loose to prevent run-off.

Press the mode selection button repeatedly to cycle through the available modes. The active mode will be indicated by an illuminated icon.

5.4 LED Work Light

The integrated LED work light illuminates the work area when the trigger is depressed. It remains on for a short period after the trigger is released.

Figure 4: DCF964B in use for heavy-duty fastening

6. Maintenance

Your DEWALT power tool has been designed to operate over a long period with a minimum of maintenance. Continuous satisfactory operation depends upon proper tool care and regular cleaning.

6.1 Cleaning

• Ventilation Slots: Regularly clean the ventilation slots on the tool to prevent overheating. Use a soft brush or dry cloth.
• Housing: Wipe the tool housing with a damp cloth. Do not use abrasive cleaners or solvents. The glass-filled nylon housing is designed to resist damage from oils and harmful solvents, but excessive exposure should still be avoided.
• Anvil: Keep the anvil clean and free of debris to ensure proper socket retention.

6.2 Lubrication

Your power tool requires no additional lubrication. All bearings are permanently lubricated.

6.3 Storage

Store the tool and battery pack in a cool, dry place, out of reach of children. Remove the battery pack from the tool before storage.

7. Troubleshooting

If your DEWALT impact wrench is not functioning as expected, consult the following common issues and solutions.

For issues not listed here, please contact DEWALT customer service.

8. Specifications

The following are the technical specifications for the DEWALT DCF964B Impact Wrench:

*Maximum initial battery voltage (measured without a workload) is 20 volts. Nominal voltage is 18 volts.

Figure 5: Max Fastening Torque Specification

9. Warranty and Support

This DEWALT product is covered by a Manufacturer Warranty. For specific details regarding your warranty coverage, please refer to the warranty card included with your purchase or visit the official DEWALT website.

For technical assistance, service, or to locate an authorized service center, please contact DEWALT Customer Service:

• Website: www.dewalt.com
• Phone: Refer to your regional DEWALT contact information.

Please have your model number (DCF964B) and serial number ready when contacting support.