Traxxas Titan 21T 550 reverse-rotation brushed motor (TRX-4) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/traxxas-titan-21t-550-motor/  (sheet CC BY 4.0)
Basis: Secondary source: Big Boys With Cool Toys (retailer, Traxxas spec copy), RC Car Action (copy of the maker's figures; the maker publishes none directly)
Catalog version: 2026-10-20

Overall (mm): length 39, width 39, height 78
- The Titan 21T is the high-torque 550 brushed motor in the TRX-4 and TRX-6 crawlers. The file is the Ø39 × 57 mm can.
- The two available copies of the spec sheet disagree on weight; both are listed. Mounting pattern is not published.
- True size, no printing tolerance added. Only published numbers are used; anything not published is said so.
- Secondary source: the numbers come from a retailer or magazine copy of the maker's specification.

dimension  value
Diameter  1.53 in (39 mm); RC Car Action reprint lists 38.9 mm
Can length  2.25 in (57 mm)
Overall length  3.07 in (78 mm)
Shaft  3 mm
Weight  8.47 oz (240 g) per retailer copy; 390 g (13.76 oz) per RC Car Action reprint
Voltage  16.8 V

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Big Boys With Cool Toys (retailer, Traxxas spec copy): TRX-4 2021 Bronco 92076-4 — web — Publisher's page; dimensions are facts — https://www.bigboyswithcooltoys.ca/products/tra92076-4-traxxas-trx4-scale-trail-2021-ford-bronco-1-10-crawler-red
- RC Car Action: Traxxas TRX-4 2021 Ford Bronco — web — Publisher's page; dimensions are facts — https://www.rccaraction.com/?p=342113

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/traxxas-titan-21t-550-motor/index.json
API: https://xemstudio.com/api/geometry?object=traxxas-titan-21t-550-motor