Reference: C15 part numbers and modern replacements

[Hanno Spoelstra]

Front wheel cylinder part no. 5300869, diameter 1-1/4"
Rear wheel cylinder part no. 5450071, diameter 1-3/8"

Originally Posted by Grant Bowker

C8, C8A and C15 follow a bit different pattern as they use more Chevrolet parts.
Bsed on parts list 175 dated January 1941 the C8 and C15 use 5300869 for the front, C8 uses 5300866 for the rear while C15 uses 5450071.

The Chevrolet Master Parts List 1928-1949 lists 5300869 as being front 1-1/4", used on all 1936-48 comm. and util. (except DS ES and FS - all 1 ton trucks). 5300866 is listed for 1936-48 comm. rear 1-3/16 and GD, HD, JD, KD, AL, BL (all 3/4 ton trucks with 11' brakes) and 5450071 for 1936-48 rear 1-3/8 GE, HE, JE, KE (all 3/4 ton trucks with 14" brakes), KF, AM, AN, BM, BN, DR, ER, FR (mixture of 3/4 and 1 ton). 1-1/4 seems to be the largest front wheel cylinder Chevrolet used in this period. For 1-1/2 and 2 ton utility (includes truck and school bus, both regular and COE cabs, single and dual rear wheel) they used a 1-1/2 rear wheel cylinder assembly 5450553. Original costs were $4.00 or less.