Really tight front brakes!

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Truck82

Full Access Member
Joined
Nov 2, 2024
Posts
211
Reaction score
420
Location
Alderton
First Name
Christopher
Truck Year
1982
Truck Model
c20
Engine Size
350
If the rotors could be turned before calipers were installed its calipers.

Although not set in stone my rule was replace calipers every second brake job. How many do you think your truck has had?
I know it's had multiple brake jobs. Probably its original calipers.
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
2,092
Reaction score
3,069
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
I know it's had multiple brake jobs. Probably its original calipers

Change the calipers when possible. After the road test you described rotors should have been very hot. Possibly both are seized. Be willing to bet pistons have varnish build up.
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
7,105
Reaction score
12,510
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
Holy ****! If your parking brake works then that’s a clean truck.
Assume it released.
Back to your regularly scheduled program.
Haha kinda ironic you had the brake warning light disconnected and left the e brake on!
Sounds like a good truck!
 

SDTECH1

Junior Member
Joined
Dec 5, 2024
Posts
10
Reaction score
40
Location
DFW TEXAS
First Name
Ron
Truck Year
1978
Truck Model
C20
Engine Size
350ci, 4-speed
Did the OP lube the sliding surfaces and the bolts? I usually use some silicone grease on the sliding bolts. They can definitely stick.
#2 I'd look at the hoses, if old they are prone to collapsing inside and restricting fluid flow.
#3 Did you make sure the proportioning valve is still centered?
#4 You could try prying the caliper outboard with a large screwdriver or pry bar.
If it's real hard to get it moving then the pistons are probably sticking bad.
Just my 56 cents worth. LOL
 

scrap--metal

Full Access Member
Joined
Sep 15, 2021
Posts
693
Reaction score
1,319
Location
MN
First Name
Calvin
Truck Year
'85, '81
Truck Model
K10, K20
Engine Size
305, 350
There is still the problem of the front discs being tight and not being able to turn by hand. How snug are disc brakes supposed to be?
You should be able to turn the front wheels by hand. There should be some resistance, if you give them a good spin and let them free wheel they might spin an additional half to one full rotations, maybe one and a half. If that's not happening, I'd bet your front wheel bearings are too tight. I went through this the first time I took apart my 10 bolt front end.
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
7,105
Reaction score
12,510
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
^What he said.
And if the front brakes aren’t getting too hot and you can feel them working then likely no brake issue. And if you snugged the wheel bearings and then backed the nut off and then basically went hand snug on the nut then it’s fine.
 

Truck82

Full Access Member
Joined
Nov 2, 2024
Posts
211
Reaction score
420
Location
Alderton
First Name
Christopher
Truck Year
1982
Truck Model
c20
Engine Size
350
^What he said.
And if the front brakes aren’t getting too hot and you can feel them working then likely no brake issue. And if you snugged the wheel bearings and then backed the nut off and then basically went hand snug on the nut then it’s fine.
The front brakes don’t get hot at all. The passenger side wheel spins fine but the driver side has resistance. There is also a on/off rubbing noise coming from the driver side when driving. Now that I have replaced the wheels bearings, I think I can rule that one out. Possible it’s a warped rotor?
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
7,105
Reaction score
12,510
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
The front brakes don’t get hot at all. The passenger side wheel spins fine but the driver side has resistance. There is also a on/off rubbing noise coming from the driver side when driving. Now that I have replaced the wheels bearings, I think I can rule that one out. Possible it’s a warped rotor?
Yeah just a little warped probably. Doesn’t take much. If it was bad you’d feel it.
The difference in how they spin is not necessarily weird. You have old brakes and just repacked the bearings. If you don’t over tighten them significantly it’s fine.
 

Truck82

Full Access Member
Joined
Nov 2, 2024
Posts
211
Reaction score
420
Location
Alderton
First Name
Christopher
Truck Year
1982
Truck Model
c20
Engine Size
350
Yeah just a little warped probably. Doesn’t take much. If it was bad you’d feel it.
The difference in how they spin is not necessarily weird. You have old brakes and just repacked the bearings. If you don’t over tighten them significantly it’s fine.
So the warped rotor is ok to leave be? I don’t want to cause and damage but don’t want to replace unless I have too
 

Grit dog

Full Access Member
Joined
May 18, 2020
Posts
7,105
Reaction score
12,510
Location
Auburn, Washington
First Name
Todd
Truck Year
1986, 1977
Truck Model
K20, C10
Engine Size
454, 350
So the warped rotor is ok to leave be? I don’t want to cause and damage but don’t want to replace unless I have too
I know you just put it all back together but if the rotors aren’t worn too thin, you could have them turned, which you talked about before. Rule of thumb if there’s not a noticeable lip on the rotor from pad wear, they can most likely be turned.
That said if you’re not feeling a significant pulsing or any at all then I wouldn’t judge just by noise.
The other factor is how much have you actually driven the truck and how hard have you used the brakes ever or since reassembly?
Deposits of pad material into the rotor (usually from keeping your foot on the brake while stopped after the brakes are hot from hard or repeated stops) are not uncommon and can feel like a mildly warped rotor. That can also go away with further use.
I wouldn’t do a thing based on your description until you do some real driving, hard brake applications from speed, etc. Test drives around the block don’t count. Just like other components it’s sometimes beneficial to give them a real workout.
Then if the pulsing comes back or gets worse think about doing something with the rotors.
Another thing you mentioned is ridges in the rotors IE the pads have been run down to the rivets before and just got a pad slap brake job.
Again not horrible as your pads are now conformed to the ridges.
When if you do something about the rotors, new pads are in order.
Bottom line sounds like what you’re hearing is not detrimental.
 

JBswth

Full Access Member
Joined
Jan 24, 2022
Posts
236
Reaction score
194
Location
Vallejo, California
First Name
James
Truck Year
1973
Truck Model
C25
Engine Size
292 cubic inches
You got the correct brake pads? Did you have to push the caliper pistons back into their bores to get the pads installed? Usually you'll have to, for them to fit correctly. The pads should just very slightly drag on the rotors; this is for self cleaning purposes.
If you have not replaced the brake hoses, it may be time to do that. Bits of rubber come off the inside of the hoses and clog the calipers so they stick. Had this happen on my OBS Burb a few years ago, and just recently changed calipers, hoses and pads on my one ton because it was beginning to have this problem. And the calipers and hoses were the original parts so it was time....
All the small black specks in the washtub are the rubber bits I'm talking about. This is the driver's side, but passenger side was just as bad there.
Second picture, you can just see the edges of the inboard pad, and the slight gap between it and the rotor.
The inside of the flex hoses can also split horizontally, so it can act like an open - close valve. Fluid will move toward the caliper, but can't return, causing it to stay partially applied. I once had that problem with my 66 Ford Galaxie, (drum brakes). The right-front brake would get tighter and tighter, and I couldn't figure out why until an OG told me about deteriorating flex hoses. Replacing that hose fixed the problem, so I replaced the others as well, as they were just as old.

J. B.
 

Truck82

Full Access Member
Joined
Nov 2, 2024
Posts
211
Reaction score
420
Location
Alderton
First Name
Christopher
Truck Year
1982
Truck Model
c20
Engine Size
350
The inside of the flex hoses can also split horizontally, so it can act like an open - close valve. Fluid will move toward the caliper, but can't return, causing it to stay partially applied. I once had that problem with my 66 Ford Galaxie, (drum brakes). The right-front brake would get tighter and tighter, and I couldn't figure out why until an OG told me about deteriorating flex hoses. Replacing that hose fixed the problem, so I replaced the others as well, as they were just as old.

J. B.
My grandpa had a similar problem when he clamped the hose down with vise grips. The flap inside the hose wouldn’t let fluid get to the caliper and the car would pull to one side like crazy. Lesson learned there
 

K5 Blazer

Supporting Member
Supporting Member
Joined
Jul 17, 2023
Posts
54
Reaction score
68
Location
Sant Cruz, CA
First Name
Holden
Truck Year
1973
Truck Model
K5 Blazer
Engine Size
6.0L LS
I would replace the front rubber brake lines and replace or rebuild both front brake calipers. Have rotors machined, if there is enough material or replace them, add new pads and be done with it.
 

ASPEC

Junior Member
Joined
Oct 29, 2024
Posts
7
Reaction score
23
Location
SURPRISE, AZ
First Name
-
Truck Year
1974
Truck Model
C2500
Engine Size
454
Glad to know you found the problem.
I don't think anyone brought this up so I will add one thing in case someone in the future has a similar question.

If you leave the calipers hanging by the hose when servicing the bearings it is possible to lose track of the position of the caliper and turn it in such a way that when you install the caliper, the hose is twisted. That would keep pressure from releasing and cause a drag. I have had more than one DIY brake job come into the shop with twisted brake hoses...
 

Truck82

Full Access Member
Joined
Nov 2, 2024
Posts
211
Reaction score
420
Location
Alderton
First Name
Christopher
Truck Year
1982
Truck Model
c20
Engine Size
350
Glad to know you found the problem.
I don't think anyone brought this up so I will add one thing in case someone in the future has a similar question.

If you leave the calipers hanging by the hose when servicing the bearings it is possible to lose track of the position of the caliper and turn it in such a way that when you install the caliper, the hose is twisted. That would keep pressure from releasing and cause a drag. I have had more than one DIY brake job come into the shop with twisted brake hoses...
I made sure the calipers weren’t left hanging be the hose. I didn’t know that twisted lines would do that. Helpful information for the future. Thank you
 

Forum statistics

Threads
44,424
Posts
957,530
Members
36,776
Latest member
Love Samantha
Top