Caterpillar Excavator Thumbs: Pro Plus, Pro, Stiff Link, and Utility
This document provides detailed technical specifications and compatibility information for Caterpillar excavator thumbs, including the Pro Plus, Pro, Stiff Link, and Utility series. It covers compatibility with various Cat excavator models, stick configurations, and bucket types.
Pro Series Thumbs
The Pro Series thumbs are designed for enhanced performance and versatility. Contact your Cat dealer for thumb compatibility based on your application and machine configuration, or if your specific configuration is unavailable. Thumb matches to GC excavators require a Long Undercarriage. Not all Thumb models are available in all regions; consult your Cat dealer for regional availability.
Compatibility with Cat Machines
Pro Series (for 311-352)
| Quick Coupler* | Cat Excavators* (311-352) | Cat Buckets |
|---|---|---|
| Cat® Pin Grabber: All | Thumb-ready Stick Machines: 312E, 313F, 313, 316E/F, 317, 320E, 323F, 323 | D Series: All |
| D, E, F Series and NGH: All | Next Generation: All |
*Contact your Cat dealer for specific compatibility of thumbs for dedicated-style couplers and D & F wheeled excavators.
Thumb-ready Machine and Stick Configurations for Pro Series
Thumb-ready machines are configured with hydraulics and a Pro Series Hydraulic Thumb mounting bracket.
Thumb-ready Machines
| 313 | 317 | 323 | |
|---|---|---|---|
| Part No. | 589-6791, 589-6792 | 598-9735 | 576-8597, 580-3172, 590-8942 |
| Stick Length | 2.8 m (9' 2") | 3.1 m (10' 2") | 2.9 m (9' 6") |
| Hydraulic System | 2 pump/2 way | 2 pump/2 way | 2 pump/2 way |
| Hydraulic Control | Tool Control | Tool Control | Tool Control |
Thumb-ready Sticks
Thumb-ready sticks include Pro Series Hydraulic Thumb mounting bracket and hydraulic mounting blocks.
| 313 | 315 | 317 | 323 | |
|---|---|---|---|---|
| Part No. | 558-2810 | 558-2810 | 585-2680 | 490-7676 |
| Stick Length | 2.8 m (9' 2") | 2.8 m (9' 2") | 3.1 m (10' 2") | 2.9 m (9' 6") |
| Stick Type | Standard | Standard | Standard | Standard |
Hydraulic Requirements and Connector Lines Groups
Specific hydraulic requirements and connector line part numbers are provided for various machine models, including:
- 311D/F RR, 312D/E, 313F, 313F GC, 313, 313 GC, 314D/E/F, 315F, 315, 315 GC, M314: Minimum Stick Length: 2.5 m (8' 2"). Mounting Bracket Group 379-7029 (Not required for machines equipped with thumb-ready stick).
- 315D, 316E/F, 317, 317 GC, M318: Minimum Stick Length: 2.6 m (8' 6"). Mounting Bracket Group 370-8613 (Not required for machines equipped with thumb-ready stick).
- 318E/F: Minimum Stick Length: 2.6 m (8' 6"). Mounting Bracket Group 370-8613.
- 320 GC, 320, 320D/E/F, 320D/E RR, 321D LCR, 323, 323F, 325F CR, 325 (B1 Linkage): Minimum Stick Length: 2.9 m (9'6"). Mounting Bracket Group 386-3919 (Not required for machines equipped with thumb-ready stick).
- 324D/E, 326F, 326 (CB1 Linkage): Minimum Stick Length: 2.95 m (9' 8"). Mounting Bracket Group 386-3919.
- 328D CR, 329D/E/F, 330, 330 GC, 330F, 335F CR (CB2 Linkage): Minimum Stick Length: 3.2 m (10' 6"). Mounting Bracket Group, HD Stick 385-9614.
- 330D, 336, 336 GC, 336D/E/F, 336E H, 336F XE, 340 (DB Linkage): Minimum Stick Lengths: 3.2 m (10' 6") or 3.9 m (12' 10").
- 345D, 349E/F, 349F, 349, 352F, 352 (TB Linkage): Minimum Stick Lengths: 3.35 m (11' 0") or 3.9 m (12' 10").
Bucket and Thumb Matching Guide
Detailed tables provide part numbers for various Cat buckets (General Duty, Severe Duty, Heavy Duty, Heavy Duty Power) and corresponding Pro Plus and Pro thumbs (Pin-on and Cat Pin Grabber interfaces). The tables specify tooth quantity and width for each bucket, and tooth configuration for each thumb.
Example: For General Duty buckets, Part No. 571-2852 (5 teeth, 750 mm width) can be matched with Pro Plus Pin-on thumb Part No. 578-2538 or Pro Cat Pin Grabber thumb Part No. 387-9760.
Note on Wheeled Excavators: When using buckets and thumbs on wheeled excavators, machine stability is improved when the outriggers and blades are down and in contact with the ground.
Pro Series Thumbs Specifications
Specifications for Pro Series thumbs are provided in detailed tables, including:
- Machine compatibility
- Thumb Style (Pro Plus, Pro)
- Interface (Pin-on, Pin Grabber)
- Part No.
- Tooth Configuration and Quantity
- Overall Width (A) in mm and inches
- Stored Height (B) in mm and inches
- Weight in kg and lb
Example: For the 311D RR machine, the Pro Plus Thumb, Pin-on interface, Part No. 578-2529, has a tooth configuration (1), 4 teeth, an overall width of 568 mm (22.4 in), a stored height of 656 mm (25.8 in), and weighs 410 kg (904 lb).
Stiff Link Thumbs
Stiff Link thumbs offer robust performance and are compatible with various Cat excavator models and quick coupler systems.
Stiff Link Compatibility
- Quick Couplers: Cat Pin Grabber, Dedicated
- Cat Excavators: B, C, D, E, F Series and NGH
- Cat Buckets: C and D Series, Next Generation
Stiff Link Matching Guide
Matching guides detail compatibility based on machine linkage, minimum stick length, bucket type (General Duty, Severe Duty, Heavy Duty, Heavy Duty Power), and thumb interface (Pin-on, Pin Grabber). Tables provide part numbers for both buckets and thumbs, along with tooth quantities and widths.
Example: For the 315D machine with a Stiff Link, General Duty bucket Part No. 552-8148 (4 teeth, 770 mm width), the compatible Pin-on thumb is Part No. 378-2324 with 4 teeth, and the Pin Grabber thumb is Part No. 378-2327 with 4 teeth.
Stiff Link Thumbs Specifications
Specifications include machine compatibility, linkage type, thumb part number, tooth configuration and quantity, dimensions (Length A, Width B, Width C), and weight.
Utility Thumbs
Utility Thumbs are designed for specific applications and offer a cost-effective solution. They are compatible with a range of Cat excavators and buckets.
Utility Thumbs Compatibility
- Quick Couplers: Cat Pin Grabber, Dedicated
- Cat Excavators: D, E, F Series and NGH
- Cat Buckets: Standard Cat Buckets, Wide Tip Cat Buckets
Note: Utility Thumbs are not compatible with Cat excavators with thumb-ready sticks. They require separate connector lines (Part No. 428-5965).
Utility Thumbs Matching Guide and Installation Hardware Requirements
Matching guides specify thumb part numbers based on bucket type (Standard or Wide Tip) and coupler configuration (Pin-on or Pin Grabber). Minimum stick lengths are provided for various machine series.
Example: For 311D RR/F RR, 312D/E, etc., with a Standard Cat Bucket, the Pin-on Utility Thumb Part No. is 450-7021, and the Pin Grabber Part No. is 450-7022.
Utility Thumbs Specifications
All Utility Hydraulic Thumbs feature two teeth. Specifications include machine interface, thumb part number, tooth configuration, dimensions (Length A, Stored Height B, Overall Width C), weight, and tip radius compatibility.
Example: For the 311D RR/F RR, etc., the Pin-on Utility Thumb, Part No. 450-7021, has tooth configuration (1), a length of 1344 mm (52.9 in), a stored height of 515 mm (20.3 in), an overall width of 355 mm (14.0 in), weighs 341 kg (751 lb), and has a tip radius of 1300 mm (51.2 in).
For more complete information on Cat products, dealer services, and industry solutions, visit www.cat.com.
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