
Deploying the telescoping mast on the 3100GT Geotechnical Drill Rig

Multiple rotary head options are available on the 3100GT Geotechnical Drill Rig

No CDL Required (Class A/B) on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig

The head can be shifted 26 in. for rotary, geotechnical, or winch access on the 3100GT Geotechnical Drill Rig

Pump options include the Moyno® 3L6 or Moyno® 3L8 on the 3100GT Geotechnical Drill Rig

The drill mast can be positioned with fold, extend, mast dump, swing, and oscillation on the 3100GT Geotechnical Drill Rig

7,000 lb. primary winch and 1,800 lb. secondary winch with Quick Change Hook on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig

Geoprobe® 3100GT Geotechnical Drill Rig running hollow stem augers.

The 3100GT Geotechnical Drill Rig has multiple rotary head options mounted on a side shifting carriage.

The auto drop hammer on the 3100GT Geotechnical Drill Rig

The drill mast has a class leading push and pull force (36,000/48,000 lbs) on the 3100GT Geotechnical Drill Rig

The drill mast on the 3100GT Geotechnical Drill Rig can easily be shifted exactly where the hole dictates.

The 3100GT Geotechnical Drill Rig telescoping mast extends for tripping out longer tooling.

The control panel on the 3100GT Geotechnical Drill Rig

The deck of the 3100GT Geotechnical Drill Rig
3100GT
Geotechnical Drill Rig

Deploying the telescoping mast on the 3100GT Geotechnical Drill Rig

Multiple rotary head options are available on the 3100GT Geotechnical Drill Rig

No CDL Required (Class A/B) on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig

The head can be shifted 26 in. for rotary, geotechnical, or winch access on the 3100GT Geotechnical Drill Rig

Pump options include the Moyno® 3L6 or Moyno® 3L8 on the 3100GT Geotechnical Drill Rig

The drill mast can be positioned with fold, extend, mast dump, swing, and oscillation on the 3100GT Geotechnical Drill Rig

7,000 lb. primary winch and 1,800 lb. secondary winch with Quick Change Hook on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig









Geotechnical sampling – Powerful, Flexible, Fast, Easy on Drillers
The Geoprobe® 3100GT Geotechnical Drill Rig is designed to quickly perform SPT borings (augers & mud rotary), collect shelby tube samples, take rock cores, and push CPT cone…all on a 19,500 GVWR truck that does not require a CDL (Class A/B) to operate.
3100GT
Geotechnical Drill Rig
Geotechnical sampling – Powerful, Flexible, Fast, Easy on Drillers
The Geoprobe® 3100GT Geotechnical Drill Rig is designed to quickly perform SPT borings (augers & mud rotary), collect shelby tube samples, take rock cores, and push CPT cone…all on a 19,500 GVWR truck that does not require a CDL (Class A/B) to operate.
Features & Options
Click on a section below to learn more about the features and options of the 3100GT.

Geoprobe® 3100GT Geotechnical Drill Rig running hollow stem augers.
Over the last 15 years Geoprobe® has increasingly been supporting customers focused on successful geotechnical investigations. On many geotech sites, the need for speed and efficiency is of the utmost importance. The specific methods of geotechnical sampling varies greatly and are usually dependent on a combination of subsurface site conditions and what is considered an acceptable practice in the geographic region. The Geoprobe® engineering team set out to design a rig specifically for geotechnical sampling that could quickly perform SPT borings (augers & mud rotary), collect shelby tube samples, take rock cores, and push CPT cone…all on a 19,500 GVWR truck that does not require a CDL to operate. From this vision, the all new Geoprobe® 3100GT was born.
Video: Rotary Head Options Overview

The 3100GT Geotechnical Drill Rig has multiple rotary head options mounted on a side shifting carriage.
The 3100GT has multiple rotary head options mounted on a side shifting carriage:
- GA4000 (4000 ft-lb, 150 rpm)
- GA4100 (4000 ft-lb, 750 rpm)
- CB5 (6000 ft-lb, 600 rpm)
- All heads provide full torque in forward and reverse
- 26-in. of head side-shift
Video: Hands-Free Function
The 3100GT features a hands-free setup for rotary work in additional to manual operation. It is used for applications such as rock coring or mud rotary.
Video: Automatic Drop Hammer Overview

The auto drop hammer on the 3100GT Geotechnical Drill Rig
The automatic drop hammer can quickly and easily be deployed without needing to be man-handled.
Video: Head Side Shift Function
The head can be side-shifted a total of 26-in. This allows for side-shifting the head for rotary work, geotechnical work, and out of the way completely when using the winches.
Video: Drill Mast Overview

The drill mast has a class leading push and pull force (36,000/48,000 lbs) on the 3100GT Geotechnical Drill Rig
The drill mast includes 105-in. of head feed travel. This gives you plenty of room to catch the odd interval, or to easily add a swivel under the head. Additionally, it has a class leading push and pull force (36,000/48,000 lbs).
Video: Positioning Options

The drill mast on the 3100GT Geotechnical Drill Rig can easily be shifted exactly where the hole dictates.
With extend, swing, mast dump, oscillation, and fold, the operator can quickly deploy and position the drill mast exactly where the hole dictates. Drill mast outriggers let you quickly setup above a mud pan as well.
Video: Winch Mast Overview

The 3100GT Geotechnical Drill Rig telescoping mast extends for tripping out longer tooling.
The telescoping winch mast reduces overall height but still allows the tripping out of 20-ft. lengths of rod when combined with the 3-ft. extension. The telescoping option allows you to set the mast height based on site and field conditions.
Video: Control Panel Functions

The control panel on the 3100GT Geotechnical Drill Rig
The manual controls provide the tactile feel that some drillers prefer and the electric control adds safe hands-free operation.

The deck of the 3100GT Geotechnical Drill Rig
High capacity hydraulics powered from the truck engine saves weight and deck space. The high flow primary pump runs at 47 gpm and 4000 psi. A separate hydraulic pump is just for the mud pump.
Video: Using the Breakout
The 7-in. clamp with breakout wrench can swing directly over the hole. It is used to clamp the rods and the breakout wrench is used to separate the joints. The clamping pressure can be adjusted as well (reducing the pressure slows the clamp down and increasing the pressure speeds the clamp up).
Video: Mud Pump Overview
Pump options for the 3100GT include the Moyno® 3L6 or Moyno® 3L8 Pumps. The pump is controlled at the control panel with an on/off switch and the flow can be adjusted with a flow dial.
Video: Hand Tool Storage
The storage holder connected to the breakout clamp is built for holding the anvil, wrench, and split spoon. The control panel has built in trays and hooks for small tool storage.
Features & Options

Geoprobe® 3100GT Geotechnical Drill Rig running hollow stem augers.
Video: Geoprobe® 3100GT Features
Over the last 15 years Geoprobe® has increasingly been supporting customers focused on successful geotechnical investigations. On many geotech sites, the need for speed and efficiency is of the utmost importance. The specific methods of geotechnical sampling varies greatly and are usually dependent on a combination of subsurface site conditions and what is considered an acceptable practice in the geographic region. The Geoprobe® engineering team set out to design a rig specifically for geotechnical sampling that could quickly perform SPT borings (augers & mud rotary), collect shelby tube samples, take rock cores, and push CPT cone…all on a 19,500 GVWR truck that does not require a CDL to operate. From this vision, the all new Geoprobe® 3100GT was born.
Rotary Head Options

The 3100GT Geotechnical Drill Rig has multiple rotary head options mounted on a side shifting carriage.
Video: Rotary Head Options Overview
The 3100GT has multiple rotary head options mounted on a side shifting carriage:
- GA4000 (4000 ft-lb, 150 rpm)
- GA4100 (4000 ft-lb, 750 rpm)
- CB5 (6000 ft-lb, 600 rpm)
- All heads provide full torque in forward and reverse
- 26-in. of head side-shift
Hands-Free Rotary Controls
Video: Hands-Free Function
The 3100GT features a hands-free setup for rotary work in additional to manual operation. It is used for applications such as rock coring or mud rotary.
Automatic Drop Hammer (Hands Free)

The auto drop hammer on the 3100GT Geotechnical Drill Rig
Video: Automatic Drop Hammer Overview
The automatic drop hammer can quickly and easily be deployed without needing to be man-handled.
Head Side Shift
Video: Head Side Shift Function
The head can be side-shifted a total of 26-in. This allows for side-shifting the head for rotary work, geotechnical work, and out of the way completely when using the winches.
Drill Mast

The drill mast has a class leading push and pull force (36,000/48,000 lbs) on the 3100GT Geotechnical Drill Rig
Video: Drill Mast Overview
The drill mast includes 105-in. of head feed travel. This gives you plenty of room to catch the odd interval, or to easily add a swivel under the head. Additionally, it has a class leading push and pull force (36,000/48,000 lbs).
Drill Mast Positioning

The drill mast on the 3100GT Geotechnical Drill Rig can easily be shifted exactly where the hole dictates.
Video: Positioning Options
With extend, swing, mast dump, oscillation, and fold, the operator can quickly deploy and position the drill mast exactly where the hole dictates. Drill mast outriggers let you quickly setup above a mud pan as well.
Telescoping Dual Winch Mast

The 3100GT Geotechnical Drill Rig telescoping mast extends for tripping out longer tooling.
Video: Winch Mast Overview
The telescoping winch mast reduces overall height but still allows the tripping out of 20-ft. lengths of rod when combined with the 3-ft. extension. The telescoping option allows you to set the mast height based on site and field conditions.
Manual Controls with Electrical Augmentation

The control panel on the 3100GT Geotechnical Drill Rig
Video: Control Panel Functions
The manual controls provide the tactile feel that some drillers prefer and the electric control adds safe hands-free operation.
High Capacity Hydraulics Powered from the Truck Engine

The deck of the 3100GT Geotechnical Drill Rig
High capacity hydraulics powered from the truck engine saves weight and deck space. The high flow primary pump runs at 47 gpm and 4000 psi. A separate hydraulic pump is just for the mud pump.
Swing Out 7 in. Breakout
Video: Using the Breakout
The 7-in. clamp with breakout wrench can swing directly over the hole. It is used to clamp the rods and the breakout wrench is used to separate the joints. The clamping pressure can be adjusted as well (reducing the pressure slows the clamp down and increasing the pressure speeds the clamp up).
Mud Pumps
Video: Mud Pump Overview
Pump options for the 3100GT include the Moyno® 3L6 or Moyno® 3L8 Pumps. The pump is controlled at the control panel with an on/off switch and the flow can be adjusted with a flow dial.
Hand Tool Storage
Video: Hand Tool Storage
The storage holder connected to the breakout clamp is built for holding the anvil, wrench, and split spoon. The control panel has built in trays and hooks for small tool storage.
Tooling & Accessories
Click on a section below to learn more about the tooling & accessories for the 3100GT.

Pushing CPT with the 3100GT
The 3100GT can be setup for CPT by using a few simple anchoring components: rod guide, anchor, and anchor bridge. Automatic head feed rate control advances the cone at a steady 2 centimeters per second specified by ASTM Standard D5778. This provides hands-free operation during advancement of each rod.
Switching from geotechnical drilling to pushing CPT is fast on the 3100GT. Running CPT is safe and simple.
Video: Interlocking Split Spoon Overview

The interlocking design self aligns during assembly and is quick to disassemble
Our patented interlocking split spoon sampler is a unique geotechnical innovation from Geoprobe® that is engineered to greatly benefit your field team. It is built to be 2X stronger, last longer, and saves both money and field time over a conventional split spoon. Additionally, it meets ASTM Standard D1586.
The interlocking design provides axial alignment of the tube halves, making for a quicker assembly of the sampler. Each time it goes together it self aligns, creating a perfect fit. With the threads aligned, the cutting shoe and drive head can be threaded to the split spoon. The threads are a multi-lead, which requires fewer turns during assembly and disassembly over conventional split spoons. Less time is spent during assembly and disassembly, which speeds up each test interval.
In additional to time savings, the interlocking split sheath has two times the strength and durability of conventional split spoons. Enhanced material properties and manufacturing result in greater longevity. Design plays an important role as well. Each interlocking point keeps the two tube halves engaged throughout the sampling process. The strength of these connections prevents the sampler from bulging in dense materials. It also keeps the tube halves tightly engaged even when over-filling of the sampler occurs.
*Split tube soil sampling system manufactured under U.S. Patent 9,551,188
Tooling & Accessories
- Cone Penetration Testing (CPT)
-
Pushing CPT with the 3100GT
Video: 3100GT CPT Setup
The 3100GT can be setup for CPT by using a few simple anchoring components: rod guide, anchor, and anchor bridge. Automatic head feed rate control advances the cone at a steady 2 centimeters per second specified by ASTM Standard D5778. This provides hands-free operation during advancement of each rod.
Switching from geotechnical drilling to pushing CPT is fast on the 3100GT. Running CPT is safe and simple.
- Interlocking Split Spoon
-
Video: Interlocking Split Spoon Overview
The interlocking design self aligns during assembly and is quick to disassemble
Our patented interlocking split spoon sampler is a unique geotechnical innovation from Geoprobe® that is engineered to greatly benefit your field team. It is built to be 2X stronger, last longer, and saves both money and field time over a conventional split spoon. Additionally, it meets ASTM Standard D1586.
The interlocking design provides axial alignment of the tube halves, making for a quicker assembly of the sampler. Each time it goes together it self aligns, creating a perfect fit. With the threads aligned, the cutting shoe and drive head can be threaded to the split spoon. The threads are a multi-lead, which requires fewer turns during assembly and disassembly over conventional split spoons. Less time is spent during assembly and disassembly, which speeds up each test interval.
In additional to time savings, the interlocking split sheath has two times the strength and durability of conventional split spoons. Enhanced material properties and manufacturing result in greater longevity. Design plays an important role as well. Each interlocking point keeps the two tube halves engaged throughout the sampling process. The strength of these connections prevents the sampler from bulging in dense materials. It also keeps the tube halves tightly engaged even when over-filling of the sampler occurs.
*Split tube soil sampling system manufactured under U.S. Patent 9,551,188
> Learn More
Specifications
Click below to view standard specifications. Specifications are subject to change without notice.
Width | 98.5 in. | 2,502 mm |
Length (transport) | 275 in. | 6,985 mm |
Length (deployed, lateral fully extended) | 319 in. | 8,103 mm |
Height (normal transport) | 120 in. | 3,048 mm |
Height (deployed; winch mast up) | 277 in. | 7,036 mm |
Height (deployed; winch mast up) | 23.1 ft. | 7.036 m |
Unit Weight (w/ typical options) | 18,200 lbs. | 8,255 kg |
Extension (fore and aft) | 15 in. | 381 mm |
Lateral (side to side) (± degrees) | 4 degrees | 4 degrees |
Oscillation (degrees from vertical) | 10 degrees | 10 degrees |
Drill Mast Dump | 45 in. | 1,143 mm |
Toe Outrigger travel | 16 in. | 406 mm |
Head Travel | 105 in. | 2,667 mm |
Head Crowd Force | 36,000 lbs. | 160.1 kN |
Head Pull Force | 48,000 lbs. | 213.5 kN |
Head Feed Carriage | Comp. Slides | Comp. Slides |
Head Sideshift | 28 in. | 711 mm |
2-Speed Rotary Drive | GA4000 | GA4000 |
Rotation Torque (Range 1) | 4,000 ft-lb | 5,423 N-m |
Rotation Speed (Range 2) | 150 rpm | 150 rpm |
Hex Adapter | 1.625 in. | 41 mm |
4-Speed Rotary Drive | GA4100 | GA4100 |
Rotation Torque (Range 1) | 4,000 ft-lb | 5,423 N-m |
Rotation Speed (Range 4) | 750 rpm | 750 rpm |
Hex Adapter | 1.625 in. | 41 mm |
Line Pull | 6,800 lbf | 30.2 kN |
Line Speed | 130 fpm | 39.6 m/min |
Cable Length | 75 ft. | 22.7 m |
Line Pull | 1,800 lbf | 8.0 kN |
Line Speed | 125 fpm | 38.1 m/min |
Cable Length | 175 ft. | 30.5 m |
Single Clamp | ||
Max Clamp Force | 21,000 lbf | 93.4 kN |
Breakout Torque | 6,000 ft-lb | 8,135 N-m |
Min Casing Size Compatible | 1.25 in. | 31.6 mm |
Max Casing Size Compatible | 7 in. | 177.8 mm |
GH6400 |
Resources
Click on a section below to view information.
3100GT (One-Sheet) |

Deploying the telescoping mast on the 3100GT Geotechnical Drill Rig

Multiple rotary head options are available on the 3100GT Geotechnical Drill Rig

No CDL Required (Class A/B) on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig

The head can be shifted 26 in. for rotary, geotechnical, or winch access on the 3100GT Geotechnical Drill Rig

Pump options include the Moyno® 3L6 or Moyno® 3L8 on the 3100GT Geotechnical Drill Rig

The drill mast can be positioned with fold, extend, mast dump, swing, and oscillation on the 3100GT Geotechnical Drill Rig

7,000 lb. primary winch and 1,800 lb. secondary winch with Quick Change Hook on the 3100GT Geotechnical Drill Rig

The breakout clamp the rods and the breakout wrench is used to separate the joints on the 3100GT Geotechnical Drill Rig

Geoprobe® 3100GT Geotechnical Drill Rig running hollow stem augers.

The 3100GT Geotechnical Drill Rig has multiple rotary head options mounted on a side shifting carriage.

The auto drop hammer on the 3100GT Geotechnical Drill Rig

The drill mast has a class leading push and pull force (36,000/48,000 lbs) on the 3100GT Geotechnical Drill Rig

The drill mast on the 3100GT Geotechnical Drill Rig can easily be shifted exactly where the hole dictates.

The 3100GT Geotechnical Drill Rig telescoping mast extends for tripping out longer tooling.

The control panel on the 3100GT Geotechnical Drill Rig

The deck of the 3100GT Geotechnical Drill Rig
.
.