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Old 05-10-2016, 07:50 PM   #1
little2fast4u
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69 hard braking question

Hello all, I just purchased my 1969 c10 long bed all original with all drum brakes and no power assist. I assume it should be pretty hard to brake sure but exactly how hard should it be? I feel like it takes more force to stop than it should even though it doesnt have a booster. Also it does pull to the left when braking and I will be addressing that this weekend.
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Old 05-11-2016, 10:08 AM   #2
little2fast4u
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Re: 69 hard braking question

any help would be greatly appreciated.
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Old 05-11-2016, 10:27 AM   #3
old Chevy guy
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Re: 69 hard braking question

The pulling to the left would tend to indicate that The front brake on the right it not working as well or not at all. Since the majority of stopping is generally on the front brakes that could explain the hard braking . It could just be way out of adjustment or have a seized up wheel cylinder . You will know better when you pull the front drums. New wheel cylinders are fairly inexpensive,if you wind up changing one go all in and just do both, it's cheap insurance. You should probably plan to pull all four wheels and do a complete inspection. Stopping is job one.
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Old 05-11-2016, 12:28 PM   #4
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Re: 69 hard braking question

My 70 all drum had rock hard brakes. The shoes ended up being glazed over. This happens when they are heated up from either riding brakes or too much hard stopping. The shoes become much harder and less efficient and the pedal pressure neeed to stop is much higher.

The next thing that is common is the brakes being installed backward. On these drums, there is a long shoe and a short shoe. The long shoe always goes to the rear most position. These can be installed backward and they fit that way easily. The result is lower clamping force. Remember the rule..."Big Brake to Back"

Another issue is over machined drums. This does two detrimental effects, the first and most impactful is the thinner wall can't absorb and dissipate braking heat as well, the shoes cook and the pedal is hard but not effective. Also when the drum is turned oversized, the diameter no longer matches the shoe, so only part of the shoe contacts the drum wall. same result.

Pulling to either side tells you that the brakes are mismatches for some or all of the reasons above. OLD CHEVY GUY is correct, take care of those wheel cylinders and always match them. A new set of shoes are pretty cheap, and drums aren't bad either. I highly recommend the NAPA Premiums. They had them in stock and my truck brakes much better, no pulling and far less pedal pressure needed.

NOTE: There are two sizes of drum brakes on our trucks. You must match them correctly. They are easily identified by the type of wheel cylinder. If your wheel cylinder has two bolts holding it on you have 2 3/4" wide shoes . Mine has 2" shoes and no bolts on the wheel cylinder.
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Old 05-11-2016, 12:34 PM   #5
fwayne
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Re: 69 hard braking question

Oh one more thing, if you put new shoes on, no matter the brand or type, you must break them in. DO NOT heat them up right away. essentially nice gentle stops with plenty of time in between to cool them off. My truck took about 50 miles of rural driving to start braking well. New drum brakes might feel a bit mushy and weak at first. Thats due to them not being a perfect match to the drum yet. A few gentle miles and they will match themselves. If all was installed properly, and the adjusters are free, be sure to brake fairly firm each time you reverse. This is how they self adjust, and your pedal will feel just right.
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Old 05-11-2016, 01:21 PM   #6
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Re: 69 hard braking question

I had a similar issue with mine, the rear brakes were dragging because the brake lines which are original had collapsed. The rubber lines gave out. So I would check all the brakes while your at it and be ready to replace all rubber lines with new, and brake drum cylinders. Just found this am that my fronts are leaking now... Oh well be working on those as well. Good luck keep us informed.
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Old 05-11-2016, 03:12 PM   #7
little2fast4u
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Re: 69 hard braking question

Thanks all for the replies I got a lot of good info. I will definitely do the brake job asap and I appreciate fwayne for the proper break-in procedure. I'd like to wait to save the money on disc and power brake conversion but like old chevy guy said stopping is job one
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