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Old 06-14-2023, 11:13 PM   #1
K10-Kansas
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Should all 4 wheels stop when you push on the brakes?

I've got my K10 up on stands because I've been working on the brakes. I think I'm done and was testing. In reverse my passenger rear spins and when I apply the brakes, the passenger rear stops and the driver's rear starts spinning.

In neutral the driver's rear spins and both stop when I put on the brakes.

In drive the driver's rear spins and when I put on the brakes, the driver's stops and the passenger's starts spinning.

I may be remembering some of this wrong. Is this normal? I bought this truck a year ago and drove it onto a trailer and then off before I began replacing and fixing things so I've never really drive it or and older truck for that matter.
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Old 06-14-2023, 11:40 PM   #2
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Re: Should all 4 wheels stop when you push on the brakes?

sounds like the brakes need adjusting, should have equal braking to both rear tires
do you have the rear brake shoes in the correct location? big shoe in back? short shoe in front?
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Old 06-15-2023, 06:43 AM   #3
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Re: Should all 4 wheels stop when you push on the brakes?

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sounds like the brakes need adjusting, should have equal braking to both rear tires
do you have the rear brake shoes in the correct location? big shoe in back? short shoe in front?
Hey Greg, good morning!

I adjusted the brakes last week. So I must have not done that well. My process was to pull off the drums and rotate the horizontal spreader until the pads were out so far that I could barely get the drums back on and the drums felt difficult to spin forwards and backwards. It probably takes 20 lbs. of force to spin the drums. I don't have a window on the backside to adjust them without removing the drum. How can I adjust them better? Thanks.
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Old 06-15-2023, 12:13 AM   #4
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Re: Should all 4 wheels stop when you push on the brakes?

If the front brakes work, the rears should self adjust over time. To speed up the process, go in reverse to 10 or 15 mph and stomp on the brakes. Repeat several times. This assumes rear drum brakes.
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Old 06-15-2023, 08:21 AM   #5
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Re: Should all 4 wheels stop when you push on the brakes?

Make a window and use a plug like this for access to the star wheel.


https://www.ebay.com/itm/1x-GM-Rubbe...-/270941799421
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Old 06-15-2023, 08:53 AM   #6
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Re: Should all 4 wheels stop when you push on the brakes?

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Make a window and use a plug like this for access to the star wheel.


https://www.ebay.com/itm/1x-GM-Rubbe...-/270941799421
Great idea thanks. I went ahead and ordered 2 of them.
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Old 06-15-2023, 08:22 AM   #7
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Re: Should all 4 wheels stop when you push on the brakes?

If they have the self adj then go in reverse and mash the brakes hard
That should adj them out
Your backing plate may already have the spot stamped where the hole needs to be
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Old 06-15-2023, 08:36 AM   #8
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Re: Should all 4 wheels stop when you push on the brakes?

Do you have the brake shoes on right.
Short shoe goes in front.
Long shoe in front might cause your non lockup of the brakes.
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Old 06-15-2023, 08:58 AM   #9
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Re: Should all 4 wheels stop when you push on the brakes?

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Do you have the brake shoes on right.
Short shoe goes in front.
Long shoe in front might cause your non lockup of the brakes.
I'll pull the drums off today and check. I've never done anything other than spin the adjuster but maybe the previous owner put something on wrong. Thanks
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Old 06-15-2023, 08:58 AM   #10
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Re: Should all 4 wheels stop when you push on the brakes?

Do you have an adjustment tool.
Much easier to use than a screwdriver.
Like this.


https://www.gearwrench.com/products/...adjusting-tool
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Old 06-15-2023, 09:22 AM   #11
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Re: Should all 4 wheels stop when you push on the brakes?

Take a pic when you pull the drum off.
We might see something out of order.
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Old 06-15-2023, 09:24 AM   #12
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Re: Should all 4 wheels stop when you push on the brakes?

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Take a pic when you pull the drum off.
We might see something out of order.
Great idea. I'll do that tonight
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Old 06-15-2023, 09:01 PM   #13
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Re: Should all 4 wheels stop when you push on the brakes?

Here's the passenger rear
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Old 06-15-2023, 09:14 PM   #14
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Re: Should all 4 wheels stop when you push on the brakes?

Here's the driver's side
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Old 06-15-2023, 09:15 PM   #15
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Re: Should all 4 wheels stop when you push on the brakes?

I've got the brakes adjusted so far our i can barely get the drums off
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Old 06-15-2023, 09:51 PM   #16
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Re: Should all 4 wheels stop when you push on the brakes?

I might pull the star wheels off, clean them up and apply some anti-seize so the self-adjusters can work (they may already but things look a bit crusty).
My limited understanding of self-adjusters is that you back up, stop and the brakes will adjust a bit each time. This assumes the self-adjusters are working.
Drums should not drag when not engaged. Disks should drag just slightly.
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Old 06-16-2023, 12:08 AM   #17
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Re: Should all 4 wheels stop when you push on the brakes?

Everything looks normal. Pads appear to be on correctly.
A good cleaning would help a bunch.
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Old 06-16-2023, 07:18 AM   #18
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Re: Should all 4 wheels stop when you push on the brakes?

Ok thanks. I'll clean everything up and if that doesn't fix it I'll either replace all the components or put on disc brakes.
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Old 06-18-2023, 12:27 AM   #19
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Re: Should all 4 wheels stop when you push on the brakes?

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Originally Posted by K10-Kansas View Post
Ok thanks. I'll clean everything up and if that doesn't fix it I'll either replace all the components or put on disc brakes.
Rear brakes provide ~25% of braking so swapping to disks is more a cosmetic thing than functional.
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Old 06-17-2023, 01:57 AM   #20
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Re: Should all 4 wheels stop when you push on the brakes?

you can buy the brake spring kits..they come with everything youll need..
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Old 06-17-2023, 06:11 AM   #21
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Talking Re: Should all 4 wheels stop when you push on the brakes?

Quote:
Originally Posted by K10-Kansas View Post
I've got my K10 up on stands because I've been working on the brakes. I think I'm done and was testing. In reverse my passenger rear spins and when I apply the brakes, the passenger rear stops and the driver's rear starts spinning.

In neutral the driver's rear spins and both stop when I put on the brakes.

In drive the driver's rear spins and when I put on the brakes, the driver's stops and the passenger's starts spinning.

I may be remembering some of this wrong. Is this normal? I bought this truck a year ago and drove it onto a trailer and then off before I began replacing and fixing things so I've never really drive it or and older truck for that matter.
what 'work' were you doing on the brakes?

what were you testing?

how did the brakes perform before you started your work?

please don't take this the wrong way but;

1 nothing in your pictures looks remotely like it was worked on recently

2 your randomly oriented pictures with the edges chopped off are difficult to follow

3 shoe backings look dinged up / damaged in a few spots, like they're not entirely concentic

can you post just one picture of each side, entire backplate in the shot, and both right side up?

that would make positive hardware verification more accurate

my initial observations;

agree with above, severe corrosion needs to be cleaned up at all of the contact points before any expectations of proper operation

those wheel cylinders look poor, the right side piston actuator stems specifically look heavily corroded

at minimum remove both wheel cylinders and take them apart to make sure they're clean inside the boots, free of moisture/corrosion, and pistons slide smoothly in the bore

caution in case this crosses your mind - do not actuate wheel cylinders with hydraulic system while drums are off

while cylinders are off, also inspect hydraulic line connections for signs of moisture/corrosion

wheel cylinders can be attacked by water through contaminated brake fluid, water intrusion through boots and piston seals, or both

brake fluid is hygroscopic - absorbs moisture, that's why only fresh sealed containers should be used and old fluid flushed < 10 years for optimal performance, more frequent for most modern systems

visible corrosion would more likely be environmental, operating in wet locations, high humidity climate, coastal areas, salted roads, etc.

100% of the hydralic brake's force comes from the wheel cylinder

if they're working, and shoes are not frozen to the backplate and adjusted as close the drums as you're describing, they have little choice but to work when hydraulic force is applied

another possible cause of the symptoms you're describing switching sides is air in the rear brake line before or near the tee

have you fully bled the entire hydraulic system? probably should have asked that first but figured you'd be past that by now but just in case

do both rear brakes hold firm when you apply the parking brake?

another word of caution - do not run drivetrain at high speeds off the ground and make rapid brake applications

that type of sudden stop can stress or break u-joints, pinions, gear teeth, etc. as opposed to tire resistence with weight of vehicle on the ground

it's worse than locking up the brakes while driving, tire friction on the road dampens the lockup somewhat, although those same components can fail in that situation as well

a smooth moderate power brake is a better way to pre-test off the ground before road testing

hopefully something there rings a bell with what led you to start working on the brakes and leads you to the cause of your symptoms and the solution

please keep us posted on your findings - good luck!
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Old 06-17-2023, 07:37 AM   #22
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Re: Should all 4 wheels stop when you push on the brakes?

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what 'work' were you doing on the brakes?
Hi and thanks for the reply and your help on this. I replaced the brake booster, brake pedal clevis and pushrod, master cylinder, master cylinder brake lines, right caliper brake line, and front calipers. I had originally had the truck on stands to work on the transmission.

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what were you testing?
To see if the brakes were working well without pulling it out of the garage.

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Originally Posted by Killer Bee View Post
how did the brakes perform before you started your work?
They seemed ok driving the truck on and off of a trailer but otherwise that is my entire driving experience with the truck. I blew a brake line and then the bleeders broke off the calipers and it had the wrong booster on the truck.

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Originally Posted by Killer Bee View Post
1 nothing in your pictures looks remotely like it was worked on recently
I haven’t worked on the drums.

Quote:
Originally Posted by Killer Bee View Post
2 your randomly oriented pictures with the edges chopped off are difficult to follow.
I tried to get close ups of each side and then 1 pic with the whole drum.

Quote:
Originally Posted by Killer Bee View Post
3 shoe backings look dinged up / damaged in a few spots, like they're not entirely concentric
Okay thanks. I’ll look closer at that.

Quote:
Originally Posted by Killer Bee View Post
can you post just one picture of each side, entire backplate in the shot, and both right side up?
Yes, absolutely I will take a picture of that today.


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Originally Posted by Killer Bee View Post
agree with above, severe corrosion needs to be cleaned up at all of the contact points before any expectations of proper operation
I would prefer to replace all of the pieces as opposed to cleaning them. I’ll go get a brake kit.

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Originally Posted by Killer Bee View Post
caution in case this crosses your mind - do not actuate wheel cylinders with hydraulic system while drums are off
Good to know. That makes sense.

Quote:
Originally Posted by Killer Bee View Post
while cylinders are off, also inspect hydraulic line connections for signs of moisture/corrosion
Sure will. I bought brake lines so I will just replace all of the rear brake lines since they are easy to reach.

Quote:
Originally Posted by Killer Bee View Post
brake fluid is hygroscopic - absorbs moisture, that's why only fresh sealed containers should be used and old fluid flushed < 10 years for optimal performance, more frequent for most modern systems
Good to know. I have completely flushed the lines and have put in new fresh fluid.

Quote:
Originally Posted by Killer Bee View Post
visible corrosion would more likely be environmental, operating in wet locations, high humidity climate, coastal areas, salted roads, etc.
That is what I suspect.

Quote:
Originally Posted by Killer Bee View Post
100% of the hydralic brake's force comes from the wheel
Oh good to know. I’ll be sure to replace those when I put in the brake kit to replace all of the springs and levers.

Quote:
Originally Posted by Killer Bee View Post
if they're working, and shoes are not frozen to the backplate and adjusted as close the drums as you're describing, they have little choice but to work when hydraulic force is applied
Okay thanks. Yeah the pads are not frozen. It sounds like replacing the cylinders would be a good idea then.

Quote:
Originally Posted by Killer Bee View Post
another possible cause of the symptoms you're describing switching sides is air in the rear brake line before or near the tee.
Oh great. How would I get that out. I have bled the brakes 6 times in 2 weeks. And I am really doing it by the book I swear. I’ve done it a dozen times on different cars in the last 30 years and have watched several professional videos tis week. I have been bottle bleeding and using a helper and have filled the bottle about 10 times at each wheel this week and no additional air is coming out.

Quote:
Originally Posted by Killer Bee View Post
have you fully bled the entire hydraulic system? probably should have asked that first but figured you'd be past that by now but just in case
I have bled each wheel at least 6 times in 2 weeks trying to figure out why the wheels haven’t seemed to stop well.

Quote:
Originally Posted by Killer Bee View Post
do both rear brakes hold firm when you apply the parking brake?
Yes, they do. I am currently putting in the parking brake and tested that. I’m waiting on my cab cable.

Quote:
Originally Posted by Killer Bee View Post
another word of caution - do not run drivetrain at high speeds off the ground and make rapid brake applications.
I have run at very slow speeds and make smooth or minimally fast braking applications.

Quote:
Originally Posted by Killer Bee View Post
that type of sudden stop can stress or break u-joints, pinions, gear teeth, etc. as opposed to tire resistence with weight of vehicle on the ground. it's worse than locking up the brakes while driving, tire friction on the road dampens the lockup somewhat, although those same components can fail in that situation as well. a smooth moderate power brake is a better way to pre-test off the ground before road testing.
Oh, good to know. Thanks.
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Old 06-17-2023, 08:03 AM   #23
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Re: Should all 4 wheels stop when you push on the brakes?

nice break down!

guess you're further along than you let on in the op, sounds like you're on the right track

so if I got this straight - park brake holds, hydraulic is weak in the rear, and lines fully bled several times

if you're all solid up front and hydraulic system is fully pressurizing and bled, sounds like wheel cylinders

when you get the rears stripped down and pull those wheel cylinders, be interested to find out what they look like

hopefully all honked up because that's an easy fix and end of the (hydraulic) line of all the work you've already done

new shoes and hardware and you'll be stopping on a dime

good luck!
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Old 06-17-2023, 08:12 AM   #24
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Re: Should all 4 wheels stop when you push on the brakes?

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nice break down!

guess you're further along than you let on in the op, sounds like you're on the right track

so if I got this straight - park brake holds, hydraulic is weak in the rear, and lines fully bled several times

if you're all solid up front and hydraulic system is fully pressurizing and bled, sounds like wheel cylinders

when you get the rears stripped down and pull those wheel cylinders, be interested to find out what they look like

hopefully all honked up because that's an easy fix and end of the (hydraulic) line of all the work you've already done

new shoes and hardware and you'll be stopping on a dime

good luck!

Thanks I appreciate it. Sounds like having new components is a great idea. It feels great to fix this thing up right.
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Old 06-17-2023, 06:52 PM   #25
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Re: Should all 4 wheels stop when you push on the brakes?

The brake pads I picked up are thinner and the pad portion is slightly longer. Did I get the wrong pads?
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