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Old 02-04-2014, 04:51 PM   #1
grayw0lf
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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?
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Old 02-04-2014, 04:56 PM   #2
grayw0lf
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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?
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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!

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Old 02-07-2014, 01:08 AM   #3
swissarmychainsaw
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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)
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Old 02-07-2014, 12:09 PM   #4
grayw0lf
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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???
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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!

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Old 02-07-2014, 12:23 PM   #5
imjeff
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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.
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Old 02-07-2014, 03:26 PM   #6
grayw0lf
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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!

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Old 02-09-2014, 12:31 PM   #7
swissarmychainsaw
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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.
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Old 02-09-2014, 01:48 PM   #8
special-K
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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
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Old 02-11-2014, 04:06 PM   #9
grayw0lf
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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.
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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!

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Old 02-11-2014, 04:22 PM   #10
swissarmychainsaw
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Re: Rear brakes gone in 15k!

Was the rubber cracking? Meaning did it need replacing anyway?
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