Army · MOS history

63A3 M1 Abrams Tank System Maintainer

Converted to 91A, dated October 1, 2009 by the source.

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91AM1 Abrams Tank System Maintainer

Documented history

M1 Abrams Tank System Maintainer

DA Pam 611-21 Table 10-4 maps predecessor MOSC 63A3 to 91A; source successor entries: 91A M1 ABRAMS TANK SYSTEM MAINTAINER; conversion effective 01 Oct 2009.

Source documents (1)

DA Pam 611-21, chapter 10, Table 10-4, Enlisted MOS Conversion Listing
1. Table 10-4, PDF p. 271 · source dated 2025
PDF page 271 (opens in a new tab)

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.