Traxxas TRX-4 Sport

Stock is as the vehicle ships. Calculated is worked from the stock figures on this page rather than stored beside them, so the two cannot drift apart. Not published means it exists but no source we could find prints it.

How these numbers were settled

The manual settles the TRX-4 gearing question.

• The 82024-4 owner's manual prints '# Spur Gear Teeth / # Pinion Gear Teeth x 15.8 = Final Gear Ratio' and states the truck 'is equipped from the factory with a 39-tooth spur gear and 17-tooth pinion gear'.
• Its chart cell for 17 pinion / 39 spur reads 36.25, and 39/17 x 15.8 = 36.25 exactly, so formula and chart agree and 15.8 is the complete reduction after the spur (transmission plus portal axles) for this single-speed truck.
• Only one formula appears: the Sport ships with the single-speed transmission (the high/low unit is optional), which is why it carries the same 15.8 constant the two-speed TRX-4 uses in low gear.
• The motor is a brushed Titan 550 21T, so KV and the cell count are left blank.
• The tire diameter of 4.64 in (117.9 mm) is from Traxxas's TRX-4 comparison chart, which lists '1.9" x 4.64" Canyon Trail': 1.9 in is the wheel, 4.64 in the tire outside diameter.
• Portal axles.
• Traxxas publishes no portal reduction; 2.5559 reproduces the manual's 15.8 constant against the single-speed 2.00:1 set and the 34/11 axle.

Sources

• Manual (PDF)astramodel.cz (opens in a new tab)
• Manual (PDF)traxxas.com (opens in a new tab)

Every figure on this page traces to one of these. Where they disagreed, the note above says which was used and why.

More from Traxxas

• Stampede 4X4 VXL
• Summit 4WD
• TRX-4 Chevrolet K10 High Trail Edition
• TRX-4 Defender
• TRX-4M Chevrolet K10 High Trail Edition
• TRX-4M Defender
• Unlimited Desert Racer
• X-Maxx 8S