The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board > The 1973 - 1991 Blazers, Jimmys, and Suburbans Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 02-04-2014, 04:51 PM   #1
grayw0lf
Registered User
 
Join Date: Apr 2004
Location: Clanton, AL
Posts: 1,253
Rear brakes gone in 15k!

It appears my brakes are dragging something awful. I changed the brakes all around when I first bought my '85 M1009 (Full size Blazer 6.2Diesel). 15,000miles later the rear brakes were completely gone. The pads are non-existant & the drums are toast. The front pads look to be also work excessively for 15k miles.

The wheels don't seem to be usually hard to spin by hand. I put her on jack stands & started her up to see if the hyrdoboost was applying pressure when running. Nope.

I replaced the front hoses & while back. Both calipers are new. I just replaced the wheel cylinders when I recently replaced the rear brakes.

I don't think it was the e-brake, because it never worked.

Can anyone think of what I'm missing? Suggestions? Ideas?
__________________
85' CUCV M1009!!! The newest addition!
6.2diesel, Th400, NP208, & only 36k miles!
70' C-10 LWB Fleetside - Looking good these days!
05' Dodge Neon
88' Winner Escape Sport 1750 - 4.3v6
94' Seadoo SP
84' Honda TRX200, bare nekkid. Just a frame & tires.

Always looking for another project or any good deal!

grayw0lf is offline   Reply With Quote
Old 02-04-2014, 04:56 PM   #2
grayw0lf
Registered User
 
Join Date: Apr 2004
Location: Clanton, AL
Posts: 1,253
Re: Rear brakes gone in 15k!

I'm running the standard military Dot 5 brake fluid, though I doubt it matters.

Only other thing to mention, I off-road in it quite a bit. Could it playing in the dirt & crawling down steep hills really make that much of a differernce?
__________________
85' CUCV M1009!!! The newest addition!
6.2diesel, Th400, NP208, & only 36k miles!
70' C-10 LWB Fleetside - Looking good these days!
05' Dodge Neon
88' Winner Escape Sport 1750 - 4.3v6
94' Seadoo SP
84' Honda TRX200, bare nekkid. Just a frame & tires.

Always looking for another project or any good deal!

grayw0lf is offline   Reply With Quote
Old 02-07-2014, 01:08 AM   #3
swissarmychainsaw
Registered User
 
Join Date: Jun 2009
Location: san francisco, ca (east bay)
Posts: 674
Re: Rear brakes gone in 15k!

Did you replace the rear brake hoses?

Maybe a collapsed line would keep them engaged.

I'm assuming the rears are drums. Are they adjusted?

Whey you jack it up, and try and turn each of the rears what's that like?
(by hand)
swissarmychainsaw is offline   Reply With Quote
Old 02-07-2014, 12:09 PM   #4
grayw0lf
Registered User
 
Join Date: Apr 2004
Location: Clanton, AL
Posts: 1,253
Re: Rear brakes gone in 15k!

The hard lines seem fine. Yes, drum in back so there are no rubber hoses to rot.

They are adjusted properly. I just replaced the adjusters & all brake hardware.

By hand, the rear wheels turn just fine. There is no more than the usual weight of turning both wheels (posi).

Is there a residual valve in the prop valve???
__________________
85' CUCV M1009!!! The newest addition!
6.2diesel, Th400, NP208, & only 36k miles!
70' C-10 LWB Fleetside - Looking good these days!
05' Dodge Neon
88' Winner Escape Sport 1750 - 4.3v6
94' Seadoo SP
84' Honda TRX200, bare nekkid. Just a frame & tires.

Always looking for another project or any good deal!

grayw0lf is offline   Reply With Quote
Old 02-07-2014, 12:23 PM   #5
imjeff
Registered User
 
imjeff's Avatar
 
Join Date: Feb 2008
Location: Tacoma Washington
Posts: 890
Re: Rear brakes gone in 15k!

Why doesn't your e-brake work? Since the rear brakes usually last sooooo long, I'm wondering if the same issue that makes them not work is keeping them partly applied.
__________________
I know a guy who's addicted to brake fluid. He says he can stop any time.
72 K10 396
75 Cj5 MPI 350 Chev
67 Chevelle 396, 4 speed
74 FXE
08 Tahoe
imjeff is offline   Reply With Quote
Old 02-07-2014, 03:26 PM   #6
grayw0lf
Registered User
 
Join Date: Apr 2004
Location: Clanton, AL
Posts: 1,253
Re: Rear brakes gone in 15k!

The e-brake appears to have a broken cable. AFter recently replacing the brake shoes again I removed the e-brake hardware from the drum.

2 things I am goign to try:
1. Replace the rubber host from the axle to the frame (forgot about that one).
2. Make sure i push in the little plunger on the prop valve via clamp of some sort while bleeding.
__________________
85' CUCV M1009!!! The newest addition!
6.2diesel, Th400, NP208, & only 36k miles!
70' C-10 LWB Fleetside - Looking good these days!
05' Dodge Neon
88' Winner Escape Sport 1750 - 4.3v6
94' Seadoo SP
84' Honda TRX200, bare nekkid. Just a frame & tires.

Always looking for another project or any good deal!

grayw0lf is offline   Reply With Quote
Old 02-09-2014, 12:31 PM   #7
swissarmychainsaw
Registered User
 
Join Date: Jun 2009
Location: san francisco, ca (east bay)
Posts: 674
Re: Rear brakes gone in 15k!

That sounds right.
My vote is the rubber lines.
But the "broken cable" is suspicious too!

Too bad it takes time to test! I suppose you could put a caliper on the rear pads and measure them each month or so.

My thinking is that since you said the wheel turns freely when you jack it up and see if it binds, that the brakes are not dragging all the time (which seems to rule out the parking brake).

My guess is that you replace the rubber lines and the problem goes away.
They are cheap too! I bought mine "in stock" from napa for like $12 or something.

Let us know what you find out.
swissarmychainsaw is offline   Reply With Quote
Old 02-09-2014, 01:48 PM   #8
special-K
Special Order

 
special-K's Avatar
 
Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,851
Re: Rear brakes gone in 15k!

There is a single brake hose in the rear. There has to be. How else could your suspension move and not fatigue the brake line the first time you drove it? Just go ahead and fix the parking brake. The parts are available,cheap,and that would eliminate any doubt of a possible cause. To answer your off road/mud question...Yes, mud or muddy water will eat brakes up real quick,especially drum brakes
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed"

GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project)
GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling)
Tim

"Don't call me a redneck. I'm a rough cut country gentleman"

R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~
special-K is offline   Reply With Quote
Old 02-11-2014, 04:06 PM   #9
grayw0lf
Registered User
 
Join Date: Apr 2004
Location: Clanton, AL
Posts: 1,253
Re: Rear brakes gone in 15k!

I replaced the rear rubber line, though I doubt it was the problem. The hose bled out a reservoir full through the rear rubber hose while replacing it. That makes me doubt it was a collapsed hose.
__________________
85' CUCV M1009!!! The newest addition!
6.2diesel, Th400, NP208, & only 36k miles!
70' C-10 LWB Fleetside - Looking good these days!
05' Dodge Neon
88' Winner Escape Sport 1750 - 4.3v6
94' Seadoo SP
84' Honda TRX200, bare nekkid. Just a frame & tires.

Always looking for another project or any good deal!

grayw0lf is offline   Reply With Quote
Old 02-11-2014, 04:22 PM   #10
swissarmychainsaw
Registered User
 
Join Date: Jun 2009
Location: san francisco, ca (east bay)
Posts: 674
Re: Rear brakes gone in 15k!

Was the rubber cracking? Meaning did it need replacing anyway?
swissarmychainsaw is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:48 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com