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Your Guide to Midland and Bendix-Style Brake Boosters for Mustangs and Cougars

Welcome to our blog, where each month, we guide you through the specifics of boosters and equip you with the knowledge you need.

This month, we're diving into the world of Midland and Bendix-style boosters for Mustangs and Cougars.

We've noticed a lot of questions about these boosters and the common challenges folks face. Often, the trouble comes from mismatching the booster-style with the correct year of the car.

The risks?

It can either wreak havoc on the inside of your booster the first time you put down the pedal or result in it not working like it's supposed to.

Always remember, if you go from manual brakes to power brakes, make sure the brake pedal matches the booster correctly. (We'll dive deeper into this subject another time).

For now, let's look at the boosters and the brake pedal rod.

It's surprising how seemingly minor details can make all the difference. Here are some telltale signs to help you match the right booster to your car.

Midland and Bendix-style boosters feature by year

Ready to switch gears? Let's break down the details of boosters for Mustangs and Cougars across different years so you can confidently match the correct booster to your car:

1967/1968 Midland booster:

  • It has a wing-style bracket permanently attached to the booster

  • The wing is located at the top left when looking at the brake pedal side

  • The rod is teardrop-shaped with no specific code

  • It uses a two-piece spacer and filter on the master cylinder rod side

Remember: Mount the spacer so the filter faces the ground and the rings on the spacer face go to the rubber seal.

1969 Bendix booster:

  • It features a crimped-style housing, possibly stamped with 6945

  • It uses a teardrop MU-1 stamped rod

  • The Boss 429 variant has an MU-2 rod and a stamped spacer plate on the pedal side

1970 Bendix booster:

  • The 1970 Bendix booster continues with the crimped-style housing

  • The rod is now straight, marked as MU-3

  • This booster type has a double diaphragm and uses a bracket

1971-1973 Bendix booster:

  • It uses an 11" single diaphragm booster

  • The rod is marked MU-4, 5, or 7 and is straight

Remember: When setting up your brake system, it's crucial to match the brake rod length from the master cylinder with the brake booster. Aim for a rod length about 0.02" shorter than what's available in the master cylinder.

If you've swapped out the master cylinder, it's a good idea to double-check the fit, especially the master cylinder rod into the master.

Aftermarket masters can have different hole sizes, affecting how the rod fits. Keep an eye on these little details to ensure a smooth and proper fit during installation.

Coming soon!

Exciting news — our top-tier, CNC precision-machined master cylinder rod length verification tool is on the verge of release.

Rest assured, we never compromise on quality.

Our machine shop is hard at work on the first release, soon to be available. Once launched, you'll be the first to know, and it'll also be featured on our website.

Experience the Power Brake Booster Exchange advantage

At Power Brake Booster Exchange, we specialize in rebuilding vacuum brake boosters for classic and sports cars.

With over 30 years of experience, our vacuum booster experts can cater to your Midland and Bendix-style booster requirements for your Mustang or Cougar.

Ensure your brake booster is fitted correctly and performing at its best by scheduling a brake booster service with our dedicated team.

Book a call with us today.

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