Arrma Big Rock 3S BLX vs Arrma Granite 3S BLXWhich Should You Buy?

The Arrma Big Rock 3S BLX and Arrma Granite 3S BLX share more DNA than almost any other pair in this hobby. Same 3S BLX power system, same 50 mph top speed, same 4WD drivetrain, and only a small price difference. The Big Rock and the Granite are priced within a few dollars of each other. Choosing between them requires looking at the details, because the broad strokes are identical.

The Big Rock is the bigger truck. At 20.47 inches long with a 12.91-inch wheelbase, it stretches past the Granite's 18.74-inch length and 11.3-inch wheelbase. Width is close at 14.57 inches for the Big Rock and 13.5 inches for the Granite. That extra 1.73 inches of length and 1.61 inches of wheelbase give the Big Rock better stability at speed and over rough terrain. When you're running full throttle over bumpy ground, the longer wheelbase bridges gaps between bumps that the Granite falls into. The Granite, being shorter, is more agile in tight spaces and rotates more willingly into turns. If your bashing spot is a small backyard, the Granite's compact size is actually an advantage.

Weight slightly favors the Granite at 6.2 lbs versus the Big Rock's 6.77 lbs. Half a pound isn't dramatic, but combined with the shorter wheelbase, it makes the Granite feel a touch more lively and responsive to input. Ground clearance is 2.05 inches on the Big Rock and 1.97 inches on the Granite, a negligible difference of 0.08 inches that you'd never notice in practice. Both trucks sit at a reasonable height for mixed-terrain bashing without being too tall for stability.

Since both trucks share the same motor, ESC, and battery platform (3200mAh 3S), performance is effectively identical. Acceleration, top speed, and runtime are the same. Both are waterproof. Both use the same differential and driveshaft components. Parts are largely interchangeable between the two, which is great if you end up owning both or know someone who runs the other model. The servo, receiver, transmitter, shocks, and most hardware are shared components. A hobby shop stocking one essentially stocks both.

The real difference is the body. The Big Rock wears a full-size crew cab pickup truck body that looks great and provides more protection for the chassis. The longer body acts like a shield, keeping more of the internal components covered during rolls and tumbles. The Granite runs a more traditional monster truck body with a shorter, boxier profile that has its own aggressive charm. Aesthetics aside, the Big Rock's longer body means it handles differently in crashes, distributing impact over a longer surface. The Granite's shorter body concentrates forces differently and is quicker to replace since it's a smaller piece of lexan.

Durability is comparable since the underlying platform is shared. Arrma's 3S BLX chassis is proven and tough. The same shock towers, same arm geometry, same metal gear differentials. If one breaks in a particular crash, the other would too in the same scenario. Aftermarket support is equally strong for both, with aluminum upgrade parts, different body options, and tuning accessories readily available.

With nearly identical pricing, this truly comes down to which body style you prefer and whether you value the Big Rock's extra wheelbase length for stability or the Granite's compact agility. Neither is the wrong choice. The Big Rock is the better straight-line truck and the better open-field basher. The Granite is the better backyard ripper and tight-space driver. For such a small difference, get the one that looks better to you and know you're getting essentially the same truck underneath.