I have a few of theories on your current problem, though (see next post).
I “believe” all 7¼” differentials came with 10” brakes (’74, until end of production).
Here is a few pictures of drum brake hardware. I hadn’t looked at each picture – but I suspect minor differences in each picture – so the picture should either match or come really close to have. At work so have limited information to pull from, atm.
11” drum brakes use a different hardware setup (so not pictured).
1970
1977
1982
1986
It is not uncommon for hardware to break or fall off, things to get rusty, axle seals to leak and/or rear wheel cylinder to leak – and each one can make drum brakes grab early or not do anything.
It is also not uncommon to have missing and/or mismatched hardware, over the years - which only invites problems.
When you remove the brake drum, Things will be dusty – but should not be oily.
If there is any evidence of anything being oily – you need to get the source of leak fixed, then clean or replace the brake shoes, clean the drum and backing plate (canned brake cleaner works great) and reassemble.
The brake linings and drum MUST be oil free – so use gloves if you must, or place tape on the linings first – or whatever (be sure to remove tape once done).
This step is actually harder to accomplish, than to say (for some people).
There are three raised locations on backing plate, per side (6 to a plate) that need a touch of wheel bearing grease (a thin film, only) at each location.
The star adjuster – I have heard from several sources two different opinions as what to do with it. One set says to apply a very small amount of wheel bearing grease to the two spots marked by red arrows.
The other set of people say to make sure all surfaces are not rusty, clean and just leave be (ie: dry).
I don’t really have an opinion as to which way - except for if car will be parked more than it will be driven – a very thin layer of grease would be a good idea (to prevent rust).
If you plan on driving car every day (like I do), dry would be best.
Other than that, ALL other drum brake parts should be clean, dry and rust free.
More thoughts in a bit.
BudW
I “believe” all 7¼” differentials came with 10” brakes (’74, until end of production).
Here is a few pictures of drum brake hardware. I hadn’t looked at each picture – but I suspect minor differences in each picture – so the picture should either match or come really close to have. At work so have limited information to pull from, atm.
11” drum brakes use a different hardware setup (so not pictured).
1970
1977
1982
1986
It is not uncommon for hardware to break or fall off, things to get rusty, axle seals to leak and/or rear wheel cylinder to leak – and each one can make drum brakes grab early or not do anything.
It is also not uncommon to have missing and/or mismatched hardware, over the years - which only invites problems.
When you remove the brake drum, Things will be dusty – but should not be oily.
If there is any evidence of anything being oily – you need to get the source of leak fixed, then clean or replace the brake shoes, clean the drum and backing plate (canned brake cleaner works great) and reassemble.
The brake linings and drum MUST be oil free – so use gloves if you must, or place tape on the linings first – or whatever (be sure to remove tape once done).
This step is actually harder to accomplish, than to say (for some people).
There are three raised locations on backing plate, per side (6 to a plate) that need a touch of wheel bearing grease (a thin film, only) at each location.
The star adjuster – I have heard from several sources two different opinions as what to do with it. One set says to apply a very small amount of wheel bearing grease to the two spots marked by red arrows.
The other set of people say to make sure all surfaces are not rusty, clean and just leave be (ie: dry).
I don’t really have an opinion as to which way - except for if car will be parked more than it will be driven – a very thin layer of grease would be a good idea (to prevent rust).
If you plan on driving car every day (like I do), dry would be best.
Other than that, ALL other drum brake parts should be clean, dry and rust free.
More thoughts in a bit.
BudW