Author Topic: Rear brake adjustor?  (Read 754 times)

Offline pcdreams

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Rear brake adjustor?
« on: March 19, 2019, 09:20:11 AM »
I've got a 78 c20 with the full floating rear axle that you have to pull the axles out to take the rotor off. Well, my back brakes aren't working I've checked the hydraulics and know the pads/wheel cyliners/hoses are good because I replaced they last summer. This past week I replaced the Master and booster, no air in the lines. I thought maybe they were just out of adjustment but when I go to the backing plate there's no hole to adjust them. WTH?  Anyway, that's why I'm here hope someone can help me out.



« Last Edit: March 19, 2019, 09:22:17 AM by pcdreams »

Offline zieg85

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Re: Rear brake adjustor?
« Reply #1 on: March 19, 2019, 10:37:28 AM »
If you don't see a place for a knock out inset in the backing plate it is in the drum.
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline MIKE S

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Re: Rear brake adjustor?
« Reply #2 on: March 19, 2019, 12:48:12 PM »
And if it is in the drum be careful not knock it into the drum. And it is almost impossible to adjust them from the drum side due to the adjuster lever in the way and being further away from the drum face. The right way to do it is cut a hole on the backing plate with it removed so you can do it right. There may even be some depressions on the plate for a guide. Usually you see this on dual rear wheel axles on a cab a chassis model because the axle is narrower and the backing plate is right up against the spring and ubolts. No clearance. In that case you have to do it from the drum side.

Offline pcdreams

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Re: Rear brake adjustor?
« Reply #3 on: March 19, 2019, 01:26:47 PM »
Ok there is a hole in the drum. It sounds like I'd be better off cutting that hole in the back. Would I be seeing the depression on the back outside, or would it be inside after taking the drum off?

Offline MIKE S

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Re: Rear brake adjustor?
« Reply #4 on: March 19, 2019, 06:29:44 PM »
Since the backing plate is stamped steel if there is a depression it would be depressed on the backside and raised on the inside. Usually it is depressed on the left and right of the backing plate because some models could be used for left or right. You might need to take it apart as to not cut the wrong side.