Product Description
Features Stronger chassis and retained hinge pin plates Steering with more clearance for stones Castellated slipper pad and sliding gear mesh 1.1 inch wider stance for better handling and bashing Plastic locknut for slipper 23T Spline servo saver 37T 1.35Mod diffs with silicone O-rings Power Module with sliding gear mesh and improved dirt management Rubber shielded bearings throughout Oil-filled shocks with silicone O-rings Wider arms front and rear Body with matte black finish Front and rear bumpers with matte black finish Tough black multi-spoke wheels with matte black finish Vented multi-terrain dBoots RAGNAROK tires BLX100 2S/3S waterproof ESC For details on waterproof standards, refer to the instruction manual. IC5 connectors (EC5) compatible Signature easy-access modular design Easy-access power module Easy-access electronics module Easy-access diff module removal front and rear Double wishbone suspension front and rear Metal-geared differentials Adjustable ride height Adjustable body mounts Adjustable turnbuckles High-speed center driveshaft support Wheelie Bar 2-year limited warranty (see website for details) 50+ MPH (80+ km/h) speed achievable in optimum driving conditions on 3S LiPo Overview A great step-up from brushed bashing, the 1/10 scale ARRMA BIG ROCK CREW CAB 4X4 3S BLX ready-to-run monster truck delivers a thrilling combination of ARRMA toughness, street truck style and 50+ mph speed capability.

About Us
ARRMA defines high-speed super-tough RC action. Designed from the ground-up by experts who understand the importance of strength, speed and value, ARRMA vehicles are 'Faster. Tougher'. With a wide range of vehicles that provide the perfect opportunity for you to enjoy dirt-blasting RC driving, learn new skills, and inspire others to share in the pulse racing world of ARRMA, your journey starts here.
Shop More ARRMA

50+ MPH Vehicles

70+ MPH Vehicles
Who are we?
ARRMA is a brand that defines high-speed super-tough RC action.
Designed from the ground-up by experts who understand the importance of strength, speed, and incredible value, ARRMA RC vehicles are 'Designed to be Fast, Designed to be Tough'.
What makes our products unique?
With a wide range of exciting RC vehicles that provide the perfect opportunity for you to enjoy dirt-blasting RC driving, learn new skills, and inspire others to share your passion for the pulse racing world of ARRMA RC, your journey starts here.

Spektrum Firma 3660 3200Kv brushless motor with Safe D pinion and ARRMA heatsink and cooling fan
Stronger chassis and retained hinge pin plates
Steering with more clearance for stones
Castellated slipper pad and sliding gear mesh
Ready to Run (RTR) completion level is fully assembled and includes everything needed besides batteries and a charger.
Overview
A great step-up from brushed bashing, the 1/10 scale ARRMA BIG ROCK CREW CAB 4X4 3S BLX ready-to-run monster truck delivers a thrilling combination of ARRMA toughness, street truck style and 50+ mph speed capability. Built on the powerful 4X4 BLX platform, its precision aluminum, tough steel and composite materials come together for an easy-to-maintain, super-durable vehicle design that's now been upgraded to further increase the monster truck's impressive performance and durability.
The BIG ROCK 4X4 3S BLX is DESIGNED FAST, DESIGNED TOUGH - built for exciting bashing speeds and extreme, all-terrain durability. New features that enhance its unstoppable performance include a stronger chassis and retained hinge pin plates; steering with more clearance for stones; a castellated slipper pad and sliding gear mesh; longer suspension arms for a 1.10 inch increase in width; and rubber-shielded bearings throughout. The SLT3 is compatible with Tactic SLT receivers to run other RTR vehicles you may own, and includes a third channel to control optional features such as lights and winches on models that have them.
ARRMA now powers the BIG ROCK 4X4 3S BLX with a brushless system featuring its BLX100 ESC and the Spektrum Firma 3200Kv brushless motor. The combination provides incredible torque, acceleration and speed. The transmission and chassis are ruggedly engineered to take full advantage of the electronics' power.
It has the ingenious modular design perfected by ARRMA engineers for easy component access and maintenance. The power module, with improved dirt management, consists of the motor with ARRMA heatsink and cooling fan, plus motor plate, slipper clutch assembly and gear cover. The power module can be detached from the chassis as a complete unit by removing just one screw. With the power module removed, the slipper clutch can be reached easily for adjustments by taking out three screws that attach the gear cover. The gear ratio can be finely tuned as the power module now uses a sliding motor mesh design.
A two-piece molding screwed to the truck's chassis serves as its electronics module, containing a waterproof receiver box, servo mount and ESC tray. The SLR300 receiver mounts inside the receiver box for protection from dirt and moisture. The ultra-compact ESC is screwed to the top of the module, allowing quick access to the on/off switch, while the servo mounts to the side. All three components can be removed together, quickly and easily.
The differential module houses each differential unit in an innovative yoke design. Only eight screws need to be removed to release the front and rear yokes. The power module can then be detached, allowing you to pivot the gearbox cases for differential access. The BIG ROCK 4X4 3S BLX RTR comes brushless-ready with 37T 1.35mod diffs with silicone O-rings. The large gears can withstand huge torque, and internal metal gears have been chosen for reliability during extreme bashing.
Its full-time 4WD transmission uses strong front, rear, and centerline telescopic driveshafts that can't be lost during heavy impacts, unlike dogbones. A simple, dependable, responsive steering assembly complements the ultra-reliable drive system and features a servo horn with built-in servo saver. The BIG ROCK 4X4 3S BLX RTR includes the waterproof Spektrum SPMS651 metal-geared digital servo for 15% more torque than the previous version's ADS-7M servo.
The self-bleeding, oil-filled shocks, now with silicone O-rings, use a tried and tested, coil-over design for simple maintenance and amazing handling. Their innovative rod-end has a molded-in spring perch for extra toughness. Extended height dirt defenders and a close-fitting body limit the amount of dirt and debris that can get into the chassis tub. Front and rear bumpers offer defense against impacts.
Accented by matte black front and rear bumpers and wheels, the BIG ROCK 4X4 3S BLX truck's long, scale Crew Cab body marks the epitome of street style. With the included dBoots RAGNAROK MT tires, you'll take it on the run over dirt tracks, trails and even muddy courses. An adjustable wheelie bar comes as standard, letting you enjoy a little stunt fun along the way.

Spektrum 3-Channel SLT3 2.4GHz radio and SLR300 Waterproof* Receiver

(1) ARRMA BIG ROCK 4X4 3S BLX 1/10 Scale 4WD Electric Monster Truck RTR BLX100 2S/3S Waterproof* ESC
(1) Spektrum Firma 3660 3200Kv Brushless Motor
(1) Spektrum 2.4GHz SLT3 3-Channel Transmitter
(1) Spektrum SLR300 Receiver
(1) Spektrum SPMS651 Waterproof* Metal-Geared Digital Servo
(1) Product Manual
Needed to Complete
2S LiPo or 3S Hardcase LiPo Battery
Compatible Charger and LiPo Safe Charging Bag
(4) AA Batteries
The BIG ROCK 4X4 3S BLX is DESIGNED FAST, DESIGNED TOUGH Ready to Run (RTR) completion level is fully assembled and includes everything needed besides batteries and a charger.
It also now includes a Spektrum SLT3 transmitter and SLR300 receiver. The transmitter is ergonomically designed for long periods of fatigue-free bashing and has a foam wheel for precise fingertip control, plus an improved hand grip and trigger feel.
Fast response SLT protocol
Foam wheel
Improved grip and trigger feel
Improved wheel and trigger force
2-way thumb switch third channel
50% and 75% Throttle mode (for beginners)
Tactic SLT receiver compatible
Power Module with sliding gear mesh and improved dirt management
Tough black multi-spoke wheels with matte black finish
50+ MPH (80+ km/h) speed achievable in optimum driving conditions on 3S LiPo

Spektrum SPMS651 Metal-Geared Digital Servo
101 oz-in (7.27 kg-cm) @ 6V
15% more torque than the previous ADS-7M servo for improved steering feel
Waterproof*
*For details on waterproof standards, refer to the instruction manual.
Easy-access power module
Detaches from chassis as a complete unit by removing one screw.
Contains motor, motor plate, slipper clutch assembly and gear cover.
Easy-access electronics module
Two-piece molding screwed to the chassis contains a waterproof receiver box, servo mount, and ESC tray.
Receiver mounts inside sealed module for protection from dirt and moisture.
ESC screws to the top for easy maintenance and switch access.
Servo mounts on the side for quick servicing.
Metal-geared differentials
Large gears can withstand huge torque, and internal metal gears have been chosen for reliability during extreme bashing.
Easy-access front and rear diff module removal.

Proven tough composite shock towers
Larger pull tab on power module
Castellated slipper pad and sliding gear mesh
Wider Stance

dBoots RAGNAROK MT tires
With the included dBoots RAGNAROK MT tires, you'll take it on the run over dirt tracks, trails and even muddy courses.
Sealed Wheels & Vented Tires stops dirt getting in and allows water to escape.
Proven Power Package
Amazing power and performance.
Tougher brushless ready transmission
Metal input spline molded into composite gear. Same gears as the ARRMA 4S.
Redesigned Steering
Steering with more clearance for stones.