ALLISON TRANSMISSION’S OIL SPECIFICATION — WHAT IT REQUIRES AND WHY IT MATTERS
Allison TES-295 is Allison Transmission’s specification for automatic transmission fluid used in Allison 1000, 2000, 3000, and 4000 series transmissions. It is NOT an engine oil specification. However, certain engine oils — specifically AMSOIL Heavy-Duty 15W-40 (ADP) — carry Allison TES-295 approval, meaning they can be used in Allison transmissions that accept TES-295 rated oil. This matters for fleet operators running Allison-equipped trucks.
WHAT IS TES-295?
- TES stands for Transmission Engineering Standard — Allison’s internal specification designation.
- TES-295 is the current-generation spec, replacing the older TES-389 and TES-468 specifications.
- Applies to: Allison 1000, 2000, 3000, and 4000 series automatic transmissions — the standard Allison lineup found in medium and heavy-duty trucks, buses, and vocational equipment across North America.
- Allison transmissions are widely used in Class 6–8 trucks, refuse vehicles, transit buses, and specialty vocational equipment.
- Some engine oils earn TES-295 approval because they meet Allison’s performance requirements — making them dual-purpose products that simplify fleet inventory.
TES-295 SPECIFICATION SUMMARY
| Requirement | TES-295 |
|---|---|
| Application | Allison 1000 / 2000 / 3000 / 4000 series |
| Fluid Type | Dedicated ATF or approved multi-purpose |
| Replaces | TES-389, TES-468 |
| Viscosity Grade | Various (ATF range) |
| Engine Oil Approvals | Select CK-4 products with explicit Allison approval |
| AMSOIL Product | ADP (Heavy-Duty 15W-40) carries TES-295 |
Important: Most Allison TES-295 applications use dedicated ATF — a separate transmission fluid, not engine oil. The engine oil angle (ADP carrying TES-295) is relevant primarily for specific applications where Allison explicitly permits its use. Always verify your specific transmission model before using engine oil in place of dedicated ATF.
AMSOIL ADP — TES-295 APPROVED
AMSOIL Heavy-Duty 15W-40 (ADP)
Full synthetic CK-4 engine oil carrying explicit Allison TES-295 approval. Also approved: EOS-4.5 (Mack), VDS-4.5 (Volvo), CES 20086 (Cummins). Simplifies fleet inventory for Allison-equipped trucks.
FREQUENTLY ASKED QUESTIONS
What is Allison TES-295?
Allison Transmission’s current fluid specification for 1000/2000/3000/4000 series automatic transmissions. Replaces older TES-389 and TES-468 specifications. It defines the performance requirements for fluid used in Allison’s commercial vehicle automatic transmissions.
Can I use engine oil in an Allison transmission?
Only if the specific engine oil carries Allison TES-295 approval AND your transmission model permits it. AMSOIL ADP (Heavy-Duty 15W-40) carries TES-295 approval. Verify your specific Allison model’s requirements before using engine oil in place of dedicated ATF.
Why does AMSOIL ADP carry Allison TES-295 approval?
ADP meets the performance requirements Allison established for TES-295, making it a multi-use product for fleet operators running Allison-equipped trucks. It simplifies inventory — one product covers the engine and, in eligible applications, the transmission.