Our large inventory of OEM Allison Transmission Parts includes a large line of new and rebuilt Allison automatic transmissions, and Allison Automatic transmission cores. All transmission parts can be shipped the same day in most cases. Call our Sales and Service Departments at 407-295-1221 or Email.

Troubleshooting Charts For Allison Transmissions AT / MT (B) / HT / V

The troubleshooting information contained in the following charts outlines the possible causes of transmission conditions and their remedies. Several possible causes are indicated; numbered items indicate suggested remedies for the causes. For Sales and Service Call America's #1 Supplier of OEM Allison Transmission Parts and Authorized Allison Dealer; TransDiesel Transmission Call us: 1-407-295-1221

D - LEAKING OIL Condition Probable Causes Suggested Remedies Oil Leaking Into Converter Housing 1. Engine crankshaft rear oil seal defective. 1. Replace crankshaft seal (refer to vehicle service manual). 2. Input charging pump lip-type seal defective. 2. Replace pump seal. 3. Input charging pump OD sealring defective. 3. Replace pump sealring. 4. Converter assembly weld cracked (non-repairable, welded torque converter assembly. 4. Replace converter assembly. 5. Torque converter pump hub worn at seal area. 5. Replace torque converter pump hub. Note: Welded converter assemblies are not repairable and must be replaced as an assembly. Transmission Fluid Leak at Output Shaft 6. Output flange seal faulty or missing. 6. Install new seal in rear of transmission housing. 7. Flange worn at seal surface. 7. Replace flange. 8. Sealant around seal OD defective. 8. Replace seal.