The Seal Ring,transmisson, cataloged under National Stock Number 2520-00-679-6974, is classified within Federal Supply Class 2520 (Vehicular Power Transmission Components) of the Vehicular Equipment Components group. The manufacturer of record is Lydall Inc Elastomer Products Group. Government technical data includes 1 specification, cited from the U.S. Government catalog. The record lists 4 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 7 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2520-00-679-6974 |
| Primary Part Number | HR166-3249 |
| Item Name | Seal Ring,transmisson |
| FSC / FSG | 2520 / 25 — Vehicular Power Transmission Components |
| Manufacturer | Lydall Inc Elastomer Products Group |
| Status | ACTIVE |
| General Characteristics Item Description | SYN RUBBER,ALLISON TMS22617;13.028 IN. OD;11.942 IN. MIN,12.182 IN. MAX ID;0.070 IN. MIN,0.086 IN. MAX THK;13.000 IN. MIN,13.006 IN. MAX BORE DIA IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| HR166-3249 PRIMARY | Lydall Inc Elastomer Products Group (USA) |
| 6758036 | Patria Land Oy (FIN) |
| 8348300 PRIMARY | U S Army Tank Automotive Command Amsta-Im-Mm (USA) |
| 6758036 PRIMARY | Allison Transmission Inc Dba Allison Transmission, Inc (USA) |
| Reference | Meaning |
|---|---|
| 897231R1 | 5/9 Secondary reference U.S. Government activity |
| 2520006796974 | 5/9 Secondary reference E.c.a Etablissement Centrald'approvisionnement Des Forces Armee |
| 147329 | 5/9 Secondary reference Komatsu American Intl Co |
| 6758036 | 5/9 Secondary reference General Motors Corp |
| 6758036 | 5/9 Secondary reference Patria Vehicles Oy |
| 897231R1 | 5/9 Secondary reference Komatsu American Intl Co |
| 897231R1 | 5/9 Secondary reference Simmons-Rand Co |
NSN 2520-00-679-6974 is a Seal Ring,transmisson, manufactured by Lydall Inc Elastomer Products Group, classified under FSC 2520, Vehicular Power Transmission Components. Status: active.
NSN 2520-00-679-6974 has 4 manufacturer part numbers on file: HR166-3249 (Lydall Inc Elastomer Products Group), 6758036 (Patria Land Oy), 8348300 (U S Army Tank Automotive Command Amsta-Im-Mm), 6758036 (Allison Transmission Inc Dba Allison Transmission, Inc).
2 possible matches (shared part number, not a government interchangeability claim): 5340-01-160-0854, 6220-01-317-5658. Verify interchangeability with system specifications before substitution.
Key specifications for HR166-3249: General Characteristics Item Description: SYN RUBBER,ALLISON TMS22617;13.028 IN. OD;11.942 IN. MIN,12.182 IN. MAX ID;0.070 IN. MIN,0.086 IN. MAX THK;13.000 IN. MIN,13.006 IN. MAX BORE DIA IN. 1 specification is documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.