Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1991 Mercury Cougar LS, 3.8 4FACTORY OEM SERVICE PROCEDURE
Fluid Capacities
FLUID CAPACITIES
| Application | Quantity | |
|---|---|---|
| Crankcase (Includes Filter) (4.6L, 5.0L & 5.8L) | 5.0 qts. (4.7L) | |
| Cooling System (Includes Heater) (5.0L & 5.8L) | 14.1 qts. (13.3L) | |
| Man. Transmission (Type F, Dexron-II or Mercon ATF) | ||
| M5R2 (Dexron-II) | 6.3 pts. (3.0L) | |
| T5OD 5-Speed Overdrive | 5.6 pts. (2.6L) | |
| Auto. Transmission (Dexron-II or Mercon) | ||
| AOD | 12.3 qts. (11.6L) | |
| A4LD | 9.5 qts. (9.0L) | |
| Differential (SAE 80W-90/API GL-5) | ||
| 7.5" Ring Gear | 3.5 pts. (1.7L) | |
| 8.75" Ring Gear | 4.0 pts. (1.9L) | |
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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