Late model booster/mc on 67-72

[chas350]

I have seen the newer plastic master cylinder booster combo on our 67-72 trucks, but can't remember where. I tried FAQ but only found the 73-87 booster/mc. I like the idea of a new plastic unit from the salvage yard for cheap and have seen them on our trucks.

Anyone able to help me with year/model info? Or if bracket/pushrod mods were necessary?

thanks!!

Oh, almost forgot, I am working on a 71 LWB 4wd, power brakes, disc front, drum rear so I need one from a disc/drum truck.

[chas350]

Bump TTT

[chas350]

nobody?

[dave2953]

When I put '89 'Burb brakes on my '68 I used one of the booster/m.c. combos you are talking about. What specifically do you need to know?

Here is a pic of it installed...is this what you're referring to?

[chas350]

Hey Dave, thanks.
Did you have to modify the push rod? Any other mods? The newer trucks had the proportioning valve down on the cross member right? Up to 87? But I see that you have one on the M/C already, did that come on the 89? I assume a front disc and rear drum prop valve should the same correct?
I am looking for an easy to find in the salvage yard and cheap unit preferably newer because all the old stuff around here has been crushed.
thanks for the pic.

chas

[dave2953]

On my 68 the rear factory brake line fit into the prop. valve from the 89 (that is the piece you see on the bottom of the m/c) The factory line for the front brakes was different, so I used the front lines from the 89 burb instead. I had to tweak them somewhat to run them along the crossmember and get them up to the master cylinder, but I got them to work. As for the booster rod, I believe I used the rod from the 89. I unscrewed it a little bit to make the throw a little longer. When the rod is threaded all the way closed (both pieces together) it pulled the pedal down towards the toe pan, which kept the brake lights on. However, it still left plenty of pedal travel to lock up the brakes without the pedal hitting the toepan. I did have to tweak the brake lamp switch so that it wasn't activated when the brakes weren't applied. Also, where the rod attaches to the pedal, the new rod wasn't quite large enough to accept that shouldered bolt. I used a dremel to wallow out the hole in the booster rod. I think that's everything, but please let me know if you have any additional questions. Sorry it took so long to respond...I was racking my brain trying to remember how I did some of this stuff. Also, here are some additional pics that show what I am talking about.

[chas350]

That sounds great, thanks!
I am planning to hit a junk yard this week to see what is out there.
Hopefully I can find something.

chas