67 Dart Brake issues

[Bankshot1966]

I have a 67 Dart GT, when going forward the brakes feel fine, as soon as I put it in reverse the pedal drops and it feels spongy, I have never seen this condition before on a car. It has all new bushings in the front, just had it aligned, so there is nothing loose that I can find. Any suggestions?

 

[Oldmanmopar]

Is it drum or disc brakes? Sounds like drums are to large in Diameter for the shoes . Or the park brake struts are on wrong. I wouldn't know any other condition that would cause this except something moving when the brakes are applied.

Partially apply the parking brake to tighten the shoes in the drums see if that changes anything.

 

[RedFish]

My best guess, Shoes not arced and adjusted properly to the drums. The entire brake assembly is somewhat floating and self centering but self adjusters aren't reliable. The more egg shaped the shoe assembly becomes the more directional friction can shift them. So braking happens at different locations and portions of the circle.

 

[Bankshot1966]

Is it drum or disc brakes? Sounds like drums are to large in Diameter for the shoes . Or the park brake struts are on wrong. I wouldn't know any other condition that would cause this except something moving when the brakes are applied.

Partially apply the parking brake to tighten the shoes in the drums see if that changes anything.

Front Disc and rear drum

 

[j par]

Try adjusting the back breaks...