Photo or diagram of 71+ disc brake master?

[davepl]

I've converted my '70 drum/drum Longhorn over to '72 disc/drum. All factory parts I bought from the same guy (Jesse) that I bought the truck from - they were parts he was going to install before he sold it. Which is a long way of saying I don't have any photos. And my manuals are all pre-disc.

The booster is larger, the prop valve is different, and even the brackets are a little beefier (can't help but wonder if this is maybe from a 3500, but no idea).

Does anyone have a good photo of an existing factory setup, or a picture of the assembly or shop manual diagram for the factory discs? Preferably big-block 2500 or larger, but I'll take what I can get!

Thanks,
Dave

[FirstOwner69]

Originally Posted by davepl

The booster is larger, the prop valve is different, and even the brackets are a little beefier (can't help but wonder if this is maybe from a 3500, but no idea).

I assume this is a comparison to what was on your 70? If so, your 70 had a distribution block. The 71/72 used a different master and booster and had a prop valve. The brackets were a bit beefier and also had a support rod to the firewall. The 71/72 3/4 tons had a different master and booster than the 1/2 tons. The brake lines were also hooked to the master reversed from the 1/2 tons. On 3/4 tons the back chamber of the master was bulged/bigger and gets connected to the front brakes.

Here's a link to a 3/4 ton booster at Rock Auto. http://www.rockauto.com/catalog/more...759&cc=1442361

Jim

[davepl]

Thanks. I have all the parts (except the lines), just not sure what brackets go where and how the lines are routed.

I'm using a new master (cheap) and disc brake prop valve (expensive).

No one makes a line kit either, it seems, so I might be winging it anyway.

[Carmen Black]

I pulled this off my "72 Custom" parts truck with power disc/drum setup. Haven't got it installed yet.

[FirstOwner69]

Originally Posted by Carmen Black

I pulled this off my "72 Custom" parts truck with power disc/drum setup. Haven't got it installed yet.

That looks like a 1/2 ton setup.

[SS Tim]

Might try downloading a 72 manual so you have some pictures and specs. Here are a couple of pictures I dug up that might start you off.
* VIN/Model Decoders
* Power Team Charts (engine/transmission/gear ratio)
* Post Your Pickup SPID Blazer SPID Suburban/Panel SPID
* RTFM ... Read The Factory Manuals... download 'em here

[FirstOwner69]

Here's a link to the 72 manual. Try section 5. It starts on PDF page 149.
http://67-72chevytrucks.com/vboard/s...d.php?t=558016

[davepl]

Hmmm... posted about 8 photos, all gone. Will try again!

[FirstOwner69]

Originally Posted by davepl

Hmmm... posted about 8 photos, all gone. Will try again!

I believe you posted them in the PDF manual thread.

[chevy72blu]

Originally Posted by FirstOwner69

I assume this is a comparison to what was on your 70? If so, your 70 had a distribution block. The 71/72 used a different master and booster and had a prop valve. The brackets were a bit beefier and also had a support rod to the firewall. The 71/72 3/4 tons had a different master and booster than the 1/2 tons. The brake lines were also hooked to the master reversed from the 1/2 tons. On 3/4 tons the back chamber of the master was bulged/bigger and gets connected to the front brakes.

Here's a link to a 3/4 ton booster at Rock Auto. http://www.rockauto.com/catalog/more...759&cc=1442361

Jim

Yep, and for some reason quite a few parts suppliers for our trucks dont know that.

There is a website where a guy took several pictures and explained it.. helped a lot when I replaced my brake system. Its proving a bit difficult to find.

[brown7373]

Pictures of my 72 1/2 ton Cheyenne

[davepl]

Well, I ordered TKT7107S from Summit, we shall see.