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Old 10-16-2020, 01:50 PM   #1
Jeepwm69
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Brakes

Well my brakes need work.

I'm pretty sure I have a sticking caliper at a minimum. Figure with the truck being 37 years old, I probably ought to replace the rubber lines, do a full system flush, and either replace or at least clean up the calipers.

If I DO need to buy a new caliper, are reman ok or should I buy new? I know some reman parts just don't last (steering gears, AC compressors).

I can get a lot of different reman calipers, but looks like Raybestos is the only new option.

When I crack the system open, is there a proportioning valve that I'm going to have to "reset" so to speak when pressure is lost?

I'm a Jeep CJ guy. The prop valves on those have a little button you have to hold out to allow fluid to go to the back. Guess it's a safety feature of some sort. Does these GM trucks have a similar setup, and if so, where's the prop valve located (I'm at work, truck is at home, and I'm trying to work up a game plan/parts order)
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Old 10-16-2020, 02:39 PM   #2
kipps
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Re: Brakes

The proportioning valve is located directly below the radiator on a crossmember. It's easiest to access from the bottom of the truck. There is no button to press. Supposedly, a plug can be removed, and a special tool installed to re-center the prop valve. This is pretty rare. Most all brake jobs can be done without worrying about that valve at all.

Definitely replace the rubber hoses. An internally collapsed hose will give the same symptoms as a sticking caliper.

I don't know much about fluid flushes. Whenever I've been messing with brakes, I'm just focused on getting rolling again. I don't want to screw around with any preventative maintenance at the same time.

I don't mind reman parts. The price is right, after all!
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Old 10-16-2020, 04:42 PM   #3
Jeepwm69
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Re: Brakes

Thanks for the response. Good to know the prop valves don't cause the grief that the Jeeps have from the same era.

I figure while I'm at it, might as well (the MAW) bleed them until I get clear fluid.
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Old 10-17-2020, 09:50 AM   #4
kglowacky
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Re: Brakes

If you are on a tight budget you can just buy the rebuilt kit for the calipers and rebuild them yourself. It consist of one rubber o ring. I bought my kit at orileys for about $6.00. You will need a air compressor and PLEASE watch your figures. DO NOT Get anywhere close with your hands and figures to the caliper when you apply air to pop the cylinder out It will come out with enough force to hurt you.(Put a piece of 2x4 in the caliper where the rotor would be before you apply air this is real important to stop the plugger from flying out of the housing) I watched a utube video and it showed how to do it with a small piece of 2x4. very easy . My brakes work fine now. Rebuilt calipers are not expensive if you choose to buy them.

Last edited by kglowacky; 10-19-2020 at 12:53 PM.
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Old 10-19-2020, 12:06 PM   #5
Jeepwm69
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Re: Brakes

Quote:
Originally Posted by kglowacky View Post
If you are on a tight budget you can just buy the rebuilt kit for the calipers and rebuild them yourself. It consist of one rubber o ring. I bought my kit at orileys for about $6.00. You will need a air compressor and PLEASE watch your figures. DO NOT Get anywhere close with your hands and figures to the caliper when you apply air to pop the cylinder out It will come out with enough force to hurt you. I watched a utube video and it showed how to do it with a small piece of 2x4. very easy . My brakes work fine now. Rebuilt calipers are not expensive if you choose to buy them.
I ordered new rubber lines, figured I would replace those just due to age, and inspect the calipers to see if they can be cleaned up or if they need to be replaced.

I actually just replaced the seals in some Honda ATV calipers, so not a horrible job. I screwed a grease zerk into the banjo bolt hole and used grease to push the piston out. I guess air would work a lot faster and with less mess, but I'm a klutz so would probably end up with an injury LOL
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Old 11-12-2020, 04:41 PM   #6
Jeepwm69
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Re: Brakes

Got my rubber lines replaced yesterday. They were in BAD shape. Was tight working on getting the steel lines loose from the old lines, but once I figure out how to do it it wasn't too bad.

For anyone looking to do it for the first time.....

Undo metal brake line from the inside of the frame rail FIRST.

Then there's a big stamped nut on the inside of the frame rail. Most of my big sockets are metric and a 24mm fit it fine.

Then you can pull the rubber line free of the frame, undo the center bracket bolt/nut, and then undo the banjo bolt and it's loose.


My brake pads were still in great shape. Truck has 39K on it now, and Dad has always been easy on brakes. Rotors looked good as well. Wheels spun freely with brake stuff removed.

I need to bleed the brakes and get the old dark fluid out of there, then hopefully everything will work correctly again. If not, I'll pull the calipers back off and disassemble them, clean them up, and replace the seals.
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Old 11-14-2020, 06:40 AM   #7
wixthedog
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Re: Brakes

If you gravity bleed or pump bleed (very slowly!) the brakes you wont have an issue. If you go to bleed and push the pedal to hard the prop valve will do its job and close to one side. There is a small plastic tool that can be bought for cheap that replaces the sensor wire at the prop valve, this locks the spool in the center position. If I'm replacing lines and have some 30+ year calipers I would always choose to replace them (and the wheel cylinders) but that's me.

The way you did the rubber lines is by far the best method.
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Old 11-17-2020, 10:59 AM   #8
1957 Chief
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Re: Brakes

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Originally Posted by Jeepwm69 View Post
Got my rubber lines replaced yesterday.
Morning brother, fellow Arkansan here. I just replaced all the brakes on this little cream puff, 71K mile 1985 with a 4.3 and a 4 speed in the floor.

Hoses, calipers pads/shoes. With what they cost, its an easy decision to change everything.

Where in Arkansas are you?

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Old 11-18-2020, 03:10 PM   #9
Jeepwm69
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Re: Brakes

I'm just north of Helena. Truck only has 39K on it, and the pads are in great shape. Dad bought it new, drove about 1 mile to and from work for 7-8 years, and the rest of the miles are me as a teenager, and him puttering around town. He has my grandfather's 95 now so I got the 83.
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Old 12-01-2020, 04:31 PM   #10
Jeepwm69
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Re: Brakes

Took it for a spin yesterday. Brakes work fine again, and I'm pretty sure one of them must have been dragging a bit because the truck rolls much easier now.

Went ahead and greased the front end while I had the wheels off and was up in there.

Thanks for the help!
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