| Factory | Number | Cross Interchange Type | Relevance |
|---|---|---|---|
| ACDelco | 17D421M | Direct Cross Interchange | 4 |
| RAYBESTOS | BD421AM | Direct Cross Interchange | 2 |
| AUTOSPECIALTY | 2642104 | Direct Cross Interchange | 2 |
| RAYBESTOS | SSRD421A | Direct Cross Interchange | 2 |
| FORD | F3DZ2001C | Direct Cross Interchange | 1 |
| FORD | F3DZ2001B | Direct Cross Interchange | 1 |
| FORD | F3DZ2001A | Direct Cross Interchange | 1 |
| FORD | E9DZ2001A | Direct Cross Interchange | 1 |
| FORD | F0DZ2001A | Direct Cross Interchange | 1 |
| NAPA | SD7308CM | Direct Cross Interchange | 1 |
| AutoZone | MKD421 | Indirect Cross Interchange | 7 |
| BENDIX | MKD421 | Indirect Cross Interchange | 7 |
| WAGNER | MX421A | Indirect Cross Interchange | 6 |
| AutoZone | D421CT | Indirect Cross Interchange | 6 |
| BENDIX | D421CT | Indirect Cross Interchange | 6 |
| WAGNER | ZX421A | Indirect Cross Interchange | 5 |
| BENDIX | L55483M | Indirect Cross Interchange | 3 |
| BENDIX | L55482M | Indirect Cross Interchange | 3 |
| ACDelco | 17D421C | Indirect Cross Interchange | 3 |
| CARDONE | 164312A | Indirect Cross Interchange | 3 |
| CARDONE | 164311A | Indirect Cross Interchange | 3 |
| CARQUEST | GMD421F | Indirect Cross Interchange | 2 |
| RAYBESTOS | PGD421M | Indirect Cross Interchange | 2 |
| AutoZone | SGD421M | Indirect Cross Interchange | 2 |
| AutoZone | PGD421M | Indirect Cross Interchange | 2 |
| AUTO EXTRA | AXMD421 | Indirect Cross Interchange | 2 |
| RAYBESTOS | SGD421M | Indirect Cross Interchange | 2 |
| CENTRIC | 30004210 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 1442112 | Indirect Cross Interchange | 1 |
| WAGNER | PD421 | Indirect Cross Interchange | 1 |
| FORD | F2SZ2001A | Indirect Cross Interchange | 1 |
| CENTRIC | 3000421 | Indirect Cross Interchange | 1 |
| AMERICAN REMANUFACTURING | 762D421 | Indirect Cross Interchange | 1 |
| WAGNER | MXF7308 | Indirect Cross Interchange | 1 |
| FORD | F2OY2001A | Indirect Cross Interchange | 1 |
| AMERICAN REMANUFACTURING | 68D421 | Indirect Cross Interchange | 1 |
| WAGNER | MX7308R | Indirect Cross Interchange | 1 |
| FORD | F2DZ2001A | Indirect Cross Interchange | 1 |
| CENTRIC | 10804210 | Indirect Cross Interchange | 1 |
| AMERICAN REMANUFACTURING | 64D421 | Indirect Cross Interchange | 1 |
| WAGNER | MX7308 | Indirect Cross Interchange | 1 |
| FORD | F1OY2001A | Indirect Cross Interchange | 1 |
| CENTRIC | 1080421 | Indirect Cross Interchange | 1 |
| AMERICAN REMANUFACTURING | 62D421 | Indirect Cross Interchange | 1 |
| WAGNER | MX7268R | Indirect Cross Interchange | 1 |
| SEARS | RHD421MSR | Indirect Cross Interchange | 1 |
| CENTRIC | 10604210 | Indirect Cross Interchange | 1 |
| BENDIX | PMD421 | Indirect Cross Interchange | 1 |
| WAGNER | MX421 | Indirect Cross Interchange | 1 |
| SATISFIED BRAKE PRODUCTS | PR421C | Indirect Cross Interchange | 1 |
| CENTRIC | 1060421 | Indirect Cross Interchange | 1 |
| BENDIX | MRD421 | Indirect Cross Interchange | 1 |
| AIMCO | SPM421S | Indirect Cross Interchange | 1 |
| SATISFIED BRAKE PRODUCTS | PR421 | Indirect Cross Interchange | 1 |
| CENTRIC | 10404210 | Indirect Cross Interchange | 1 |
| BENDIX | MKD421FM | Indirect Cross Interchange | 1 |
| AIMCO | SPC421S | Indirect Cross Interchange | 1 |
| SATISFIED BRAKE PRODUCTS | CL421 | Indirect Cross Interchange | 1 |
| CENTRIC | 1040421 | Indirect Cross Interchange | 1 |
| CARQUEST | GMD421 | Indirect Cross Interchange | 1 |
| AIMCO | SD421S | Indirect Cross Interchange | 1 |
| ROCKHILL | MD421 | Indirect Cross Interchange | 1 |
| CENTRIC | 10204210 | Indirect Cross Interchange | 1 |
| CARQUEST | GCD421 | Indirect Cross Interchange | 1 |
| AIMCO | PM421 | Indirect Cross Interchange | 1 |
| RAYLOC | UP7475 | Indirect Cross Interchange | 1 |
| CENTRIC | 1020421 | Indirect Cross Interchange | 1 |
| CARQUEST | BMD421 | Indirect Cross Interchange | 1 |
| EIS | QMX421 | Indirect Cross Interchange | 1 |
| RAYLOC | UP7222AX | Indirect Cross Interchange | 1 |
| CENTRIC | 10004210 | Indirect Cross Interchange | 1 |
| CARQUEST | BMD324 | Indirect Cross Interchange | 1 |
| EIS | MX421 | Indirect Cross Interchange | 1 |
| RAYLOC | TS7475 | Indirect Cross Interchange | 1 |
| CARQUEST | BCD421 | Indirect Cross Interchange | 1 |
| EIS | DX421 | Indirect Cross Interchange | 1 |
| RAYLOC | TS7222AM | Indirect Cross Interchange | 1 |
| CENTRIC | 1000421 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2842103 | Indirect Cross Interchange | 1 |
| EIS | DM421 | Indirect Cross Interchange | 1 |
| RAYLOC | SS7222AM | Indirect Cross Interchange | 1 |
| CARQUEST | RMD421 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 28421 | Indirect Cross Interchange | 1 |
| EIS | DE421 | Indirect Cross Interchange | 1 |
| RAYLOC | SD7222AM | Indirect Cross Interchange | 1 |
| CARQUEST | RD421 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2742103 | Indirect Cross Interchange | 1 |
| WAGNER | ZX421 | Indirect Cross Interchange | 1 |
| RAYLOC | CMX7222A | Indirect Cross Interchange | 1 |
| WAGNER | SX7308 | Indirect Cross Interchange | 1 |
| RAYLOC | AE7475 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 27421 | Indirect Cross Interchange | 1 |
| ACDelco | 14D421M | Indirect Cross Interchange | 1 |
| PARTS PLUS | PPD421M | Indirect Cross Interchange | 1 |
| MOTORCRAFT | BR14B | Indirect Cross Interchange | 1 |
| RAYBESTOS | PGD421AQS | Indirect Cross Interchange | 1 |
| PARTS PLUS | PPB421M | Indirect Cross Interchange | 1 |
| RAYMOLD | RRD421M | Indirect Cross Interchange | 1 |
| PARTS PLUS | PPB324 | Indirect Cross Interchange | 1 |
| NASCAR | 01602864 | Indirect Cross Interchange | 1 |
| RAYBESTOS | PGD421AM | Indirect Cross Interchange | 1 |
| WESTERN BRAKE | WSD421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | MDS421 | Indirect Cross Interchange | 1 |
| PARTS PLUS | MD421 | Indirect Cross Interchange | 1 |
| BRAKE PRO | 4979421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | MD421 | Indirect Cross Interchange | 1 |
| PARTS PLUS | 210430421 | Indirect Cross Interchange | 1 |
| BRAKE PRO | 4970421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | DS324 | Indirect Cross Interchange | 1 |
| NAPA | TS7222AM | Indirect Cross Interchange | 1 |
| KEMPARTS | MD421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 421Z | Indirect Cross Interchange | 1 |
| RAYBESTOS | BD421M | Indirect Cross Interchange | 1 |
| NAPA | PE7222AM | Indirect Cross Interchange | 1 |
| KEMPARTS | CMD421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 4214 | Indirect Cross Interchange | 1 |
| AutoZone | DGC421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | RRD421M | Indirect Cross Interchange | 1 |
| NAPA | CMX7222A | Indirect Cross Interchange | 1 |
| PEP BOYS | PD421MR | Indirect Cross Interchange | 1 |
| GUARANTEED | 61421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 4212 | Indirect Cross Interchange | 1 |
| AutoZone | DG421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | RRD421AM | Indirect Cross Interchange | 1 |
| NAPA | AE7222AM | Indirect Cross Interchange | 1 |
| PEP BOYS | MD421 | Indirect Cross Interchange | 1 |
| AUTO EXTRA | SMD421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 4211 | Indirect Cross Interchange | 1 |
| RAYBESTOS | SSRD421 | Indirect Cross Interchange | 1 |
| RAYBESTOS | PGD421QS | Indirect Cross Interchange | 1 |
| MIGHTY | TS324 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2642102 | Indirect Cross Interchange | 1 |
| WAGNER | SX421 | Indirect Cross Interchange | 1 |
| Morse Brake | MKD421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 042120 | Indirect Cross Interchange | 1 |
| A.B.S. | 38421 | Indirect Cross Interchange | 1 |
| AutoZone | BR14B | Indirect Cross Interchange | 1 |
| GUARDIAN | 65421 | Indirect Cross Interchange | 1 |
| WAGNER | PX7308R | Indirect Cross Interchange | 1 |
| Morse Brake | D421 | Indirect Cross Interchange | 1 |
| PERFORMANCE FRICTION | 042110 | Indirect Cross Interchange | 1 |
| KEMPARTS | PXD421 | Indirect Cross Interchange | 1 |
| FEDERATED | MD421 | Indirect Cross Interchange | 1 |
| GUARDIAN | 61421 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2442104 | Indirect Cross Interchange | 1 |
| WAGNER | PX7268R | Indirect Cross Interchange | 1 |
| Morse Brake | CMX421 | Indirect Cross Interchange | 1 |
| GUARANTEED | 65421 | Indirect Cross Interchange | 1 |
| KEMPARTS | MXD421 | Indirect Cross Interchange | 1 |
| FEDERATED | FSMD421 | Indirect Cross Interchange | 1 |
| FMSI | D5977475 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2442102 | Indirect Cross Interchange | 1 |
| WAGNER | PX421 | Indirect Cross Interchange | 1 |
| GM | 18029006 | Indirect Cross Interchange | 1 |
| Morse Brake | SXE421 | Indirect Cross Interchange | 1 |
| FMSI | D4217308A | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 2432404 | Indirect Cross Interchange | 1 |
| FORD | E9DZ2001B | Indirect Cross Interchange | 1 |
| Morse Brake | MX421 | Indirect Cross Interchange | 1 |
| FEDERAL MOGUL | MKD421 | Indirect Cross Interchange | 1 |
| AUTOSPECIALTY | 1642112 | Indirect Cross Interchange | 1 |
| WAGNER | PD7308R | Indirect Cross Interchange | 1 |