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-   -   WHOA....those are brakes (https://67-72chevytrucks.com/vboard/showthread.php?t=190863)

shelby987 02-27-2006 11:38 AM

WHOA....those are brakes
 
So I was told a couple of years ago regarding my fathers truck that I didn't need to swap out for disc. brakes, just put on a booster.....always figured the guy was crazy.....but my trucks brakes have been wearing on my right knee (That I have already had scoped once, and need to have done again)....so this weekend I swapped in a booster....needless to say the time spent crammed between the floor and the steering wheel were well worth it....I can hardly touch the brakes without them locking up, almost bounced my girlfriend off the dashboard, she thought I was messing with her.

I only have MAYBE 2" of travel....and using much more than the first 1" will lock these things up.....is this correct? It is a 3/4t booster....its HUGE!

What are advantages of switching to disc brakes down the road? disadvantages to drums? (plan on the swap, its just not as immediate now that I have power brakes).

boundstaffpress 02-27-2006 01:21 PM

Re: WHOA....those are brakes
 
I had a 69 impala with touchy brakes like that. Someone swapped a booster out of our trucks into that car, and it would stop on a dime. I laughed as the next owner drove off, then tried to slow at the corner and almost lost control. I had told him, but you now know that "The brakes are touchy" doesn't really describe just how quick they kick in.

speedracer 02-27-2006 01:31 PM

Re: WHOA....those are brakes
 
drum brakes have more surface area then disc "aka" better stopping power. but the drum holds heat in so if you ride them they overheat, crack, and glaze over.

shelby987 02-27-2006 02:07 PM

Re: WHOA....those are brakes
 
I use my transmission to slow me down more than anything else.....always prefered downshifting to braking.....much more controlled.....but I can see how these things could hold in heat......the front's aren't even finned!

Bowtie67 02-27-2006 02:52 PM

Re: WHOA....those are brakes
 
In most cases drum brake setup are lighter than disk bracks unless your spending the big bucks getting the real light stuff.

Longhorn Man 02-27-2006 03:41 PM

Re: WHOA....those are brakes
 
You may need to back off the adjustment on the pushrod a bit.
When the truck is cooled down... like a few hrs with no driving, depress the pedal lightly with your hand. You are looking for some freeplay. I'm thinking there's supposed to be something like 1/4 to 1/2 inch freeplay... something like that.

The fluid expands a little with heat, and since drums retain heat, the fluid heats up. Havinf drums up front increases the heat by more than 100% since they do 75% of the work. This increases the amount of slack, or room needed to expand.

When I replaced the master cylinder on my first truck(70 CST/20 Longhorn) I over adjusted that push rod, and once i got on the freeway I noticed it was suffering from LOA (lack of @ss). Once I got on the next off ramp, it was draggin even worse, and then I smelled the rear brakes. They were slightly applied becouse the fluid had expanded. I popped the master off, turned on the rod end about 1/2 turn, bolted it back up...tail lights and tire smoke.

shelby987 02-27-2006 05:07 PM

Re: WHOA....those are brakes
 
The pushrod is the rod connected to the pedal correct? I know there is a locking nut behind the section that has the pin through it connecting it to the pedal......Do I have to take the mc/booster assembly off to turn this rod? Or am I better to take the other end of the rod off the assembly by the firewall?
Thanks

Frizzle Fry 02-27-2006 05:15 PM

Re: WHOA....those are brakes
 
Quote:

Originally Posted by shelby987
I use my transmission to slow me down more than anything else.....always prefered downshifting to braking.....much more controlled.....but I can see how these things could hold in heat......the front's aren't even finned!

I used to do that too until a mechanic told me "you're better off replacing brake pads than a clutch." Makes sense to me. Why wear out the clutch faster than needed? Now I only own autos, but I thought I'd pass it on.

Longhorn Man 02-27-2006 05:49 PM

Re: WHOA....those are brakes
 
Remove the master cylinder and there should be a small maybe 3/8 inch diameter rod poking out. Tug on it and it'll pop right out. Look at it and it kinda looks like a pushrod in an engine, but one end is adjustable.


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