Choosing the Right Rear Brake Drum for Your 1975-1979 Mercury Cougar
Everything you need to know before replacing the rear brake drums on your classic Cougar.
- For this classic car, you are buying aftermarket parts. New OEM Ford drums are not available.
- Always replace brake drums, shoes, and hardware in pairs to ensure even and safe braking.
- Have new aftermarket drums inspected for balance and roundness at a machine shop before installation to avoid vibration issues.
- While replacing the drums, inspect the wheel cylinders and rubber brake hoses, which are common failure points on older vehicles.
Signs of a Worn Brake Drum
Your Cougar's brakes will give you clear signals when the drums are worn out. Ignoring these symptoms can lead to unsafe driving conditions and more expensive repairs down the road. Pay attention to these common signs:
- Pulsing or Vibration: If you feel a pulsing sensation in the brake pedal when you slow down, it often means the drum is "out-of-round." This variation in the drum's shape causes uneven braking.
- Scraping or Grinding Noises: A loud grinding or scraping sound from the rear of the car when braking is a critical warning. It usually means the brake shoes are completely worn away and metal is grinding against the drum, causing severe damage.
- Loud Bang or "Grenade" Sound: In some cases of severe failure, internal hardware can break apart inside the drum, causing a loud noise and a total loss of braking on that wheel.
- Poor Parking Brake Performance: If your parking brake doesn't hold the car securely on a hill, it can be a sign that the drums are worn beyond their service limit.
Choosing Your Aftermarket Brake Drum
For a classic car like the 1975-1979 Cougar, finding new Original Equipment Manufacturer (OEM) parts from Ford is not a realistic option. The market consists of new aftermarket parts. The quality of these parts can vary, and it's important to understand the differences between brands.
A common issue with aftermarket drums for classic cars is that they can arrive out-of-round or unbalanced, even from reputable brands. This can cause vibrations. It is a wise pro-tip to have a machine shop check the balance and concentricity of new drums before you install them.
Brand Quality Tiers
Here’s an honest look at the brands available for your Cougar, based on general reputation and user feedback.
- Premium / Professional Grade (Bendix): Bendix is a historic brand that was a pioneer in brake systems. They are generally positioned as a high-quality or professional-grade option. While the brand has a strong legacy, some users feel modern parts don't always live up to the historic quality, but it remains a top-tier choice in the aftermarket.
- Daily Driver Grade (Centric): Centric is a major aftermarket manufacturer known for producing parts that meet or exceed original specifications. Their drums are made from quality G3000 cast iron and are designed for a direct fit. They are a solid, reliable choice for everyday driving and offer good value. While the drums are generally well-regarded, some users have reported quality control issues with other Centric brake components like hardware kits.
- Standard / Economy Grade (Raybestos): Raybestos is a well-known name that offers different lines of products. Their R-Line drums are widely available and often priced competitively. However, owner experiences are mixed. Some users have reported receiving drums that were poorly balanced or had manufacturing defects right out of the box. Because of this inconsistency, they are often considered a standard or economy-level choice.
| Part Type | Our Price Range (Per Pair) | Shop Labor (Per Pair) |
|---|---|---|
| New Aftermarket Brake Drum | $99.37 - $162.63 | $150 - $300 |
Frequently Asked Questions (FAQ)
Do I have to replace brake drums in pairs?
Yes. You must always replace brake drums in pairs (both rear wheels at the same time). This ensures that braking is even on both sides of the axle, preventing the car from pulling to one side when you stop. You should also install new brake shoes and a new hardware kit at the same time.
What other parts should I inspect when replacing my drums?
When working on the brakes of a classic car, it's a good time for a full inspection. Check the wheel cylinders for any signs of brake fluid leaks. Inspect the old rubber brake hoses, as they can collapse internally and cause problems. On these Cougars, also pay attention to the brake proportioning valve, which can get stuck and cause pressure issues between the front and rear brakes.
What does "out-of-round" mean?
An out-of-round drum is one that is no longer perfectly circular. This can happen from heat and wear. As the drum spins, the brake shoes grab unevenly, which you feel as a pulsing or vibration in the brake pedal. New aftermarket drums can sometimes be out-of-round from the factory due to manufacturing tolerances.
Are there any recalls for my Cougar's brakes?
No. Searches of the National Highway Traffic Safety Administration (NHTSA) database did not find any brake-specific safety recalls for the 1975-1979 Mercury Cougar. A recall was issued for the 1979 model, but it concerned the front seat mounting hardware, not the brakes.
Technical Specifications
OEM Part Numbers: D4OZ1126A D2OZ1126B D2OZ1126C
Brake System: Rear Drum Brake Drum Size: 11 in. x 2-1/4 in. Wheel Bolt Holes: 5
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.