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Discussion Starter · #1 ·
What is the average life people are seeing with the rubber bushings which sit it the 'ears' of the FT calipers?

I ask because I have approximately 20,000 miles on AutoZone lifetime calipers, that I maintained with Cermalub & Pastelub respectively.

Today I took apart the calipers and pins, because the car was pulling. I found that the o-rings were pretty torn up. I'm really surprised as I maintain my car very well, and didn't expect to see these o-rings so beat up after just 20K miles.

What are others getting for the life of your calipers?

Thanx.
 

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I have about 16k on new O-rings, stock calipers on mine and they are holding up pretty good.
 

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What is the average life people are seeing with the rubber bushings which sit it the 'ears' of the FT calipers?

I ask because I have approximately 20,000 miles on AutoZone lifetime calipers, that I maintained with Cermalub & Pastelub respectively.

Today I took apart the calipers and pins, because the car was pulling. I found that the o-rings were pretty torn up. I'm really surprised as I maintain my car very well, and didn't expect to see these o-rings so beat up after just 20K miles.

What are others getting for the life of your calipers?
The answers you're asking for will range and probably not address your concerns. Across the board, the answer is (should be) well over 20k and you shouldn't be seeing the degradation you are. Rather than dwell on what went on last time, a more proactive response would be to get a new kit w/ bushings and slide pins and swap out all hardware on that side at least and both sides at best. Make sure the eyelet the bushing seats inside of is clean and true. Dirt and oil buildup can constrict the bushing which, in turn, binds against the slide pin.
 

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Discussion Starter · #4 ·
The answers you're asking for will range and probably not address your concerns. Across the board, the answer is (should be) well over 20k and you shouldn't be seeing the degradation you are. Rather than dwell on what went on last time, a more proactive response would be to get a new kit w/ bushings and slide pins and swap out all hardware on that side at least and both sides at best. Make sure the eyelet the bushing seats inside of is clean and true. Dirt and oil buildup can constrict the bushing which, in turn, binds against the slide pin.
The repair kit and new pins were ordered from RockAuto last night. I wanted to get a general 'feeler' for what type of mileage people have gotten out of the calipers.
 

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Caliper Bushings

I rebuilt the brakes on the 1996 Caprice less than 30,000 miles ago. New calipers from NAPA
with hardware, pads, etc. My daughter has been complaining that the brakes feel funny??
Saturday I got the car up on jack stands and bled the brakes. The rear lines had some air
so I thought that was the problem. Went to the front, and found that the calipers were loose
in the brackets. Pulled them apart and the O rings on both sides were soft and looked like
they were turning into mush. Never had that happen before and I have been into the brakes
on both B-bodies numerous times. Found a GM bushing kit in my parts stash, its probably
10 years old and installed all new bushings and O-rings. I did notice that the rings in the GM
kit were orange colored and were very stiff compared to the NAPA parts. We will see how
they hold up.

I wonder if the "new" replacement parts are Chineese Junk or if the Cerama Lube I use was
the problem. Although I have been using it on all my vehicles for years with no problems until
now.
 

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Some types of lube will turn a rubber bushing into a gel. Make sure you use silicon grease. It would be nice if repair kits contained a proper grease as well both for metal and rubber parts.
 

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Steve,

Several things here that perhaps need to be reinforced--for everyone.

Remanufactured front calipers typically come with new bushings, sleeves, and caliper bolts. That said, the question then is--as has been alluded to--what is the source and quality of the bushings (the rubber parts)? On top of that, what lubricant, if any, was used during the reman process--and is it adequate? I think caution dictates re-lubricating all of the appropriate areas before installation of any replacement calipers--new or reman. I also will add to that--are the caliper bolts (slide pins) the correct length (9C1 calipers require longer bolts)?

The intent--by GM--was that any time the brake pads are replaced, that the caliper bushings & sleeves are replaced at the same time. The OE/production service pad kits were delivered with a package of new bushings & sleeves--this kit is available separately, or in equivalent form in the aftermarket. I cannot confirm whether they all use the same high-temp bushings as the GM kits below.

18008106 - BUSHING KIT, caliper, OE, all applications (one kit per car)
contains 8 bushings, 4 inner sleeves, and bushing lube
NOTE: PN change from 18005606

18034639 - HARDWARE (BUSHING) KIT, caliper, ACD Durastop, all applications (requires two kits per car)
contains 4 bushings, 2 inner sleeves, also includes inner pad clip, DOES NOT include lube

The caliper bolts are not included in production pad service kits, but they require inspection at the same time to ensure they are not grooved or that the plating is (not) compromised allowing corrosion to develop that will just grind away at the outer (small) bushings.

A proper lubricant is key--to provide actual lubrication over a wide temperature range, and to resist moisture intrusion and washout. Ceramlub & Pastelub (silicone based) meet these criteria and are not the problem, from my experience.

One thing you have to remember is that you relocated to a much harsher environment (TX to PA), especially the cold/wet season. GM's recommendation to service the bushings at pad change is a minimum, and I think you might want to try doing the bushing & lube service once per year--and use the OE high-temp orange silicone bushings.

You're doing the right thing--baseline the spec requirements--and let us know how it works out!
 

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Discussion Starter · #8 ·
Steve,

Several things here that perhaps need to be reinforced--for everyone.

Remanufactured front calipers typically come with new bushings, sleeves, and caliper bolts. That said, the question then is--as has been alluded to--what is the source and quality of the bushings (the rubber parts)?
My thought as well going into this whole predicament, and hence my reason for asking others.

That's the reason I went wit AC-DELCO replacement parts for the calipers.

On top of that, what lubricant, if any, was used during the reman process--and is it adequate?
Cermlub & Pastlub each in their appropriate applications per the manufacturers recommendations.

I think caution dictates re-lubricating all of the appropriate areas before installation of any replacement calipers--new or reman.
Agreed, and that was done. As I am quite anal retentative, and I get paid to be in my profession. It carries over to my personal life, which can not be helped, and is not really a bad thing when it comes to my vehicles.


I also will add to that--are the caliper bolts (slide pins) the correct length (9C1 calipers require longer bolts)?
I'm well aware of that, and have been using them.

The intent--by GM--was that any time the brake pads are replaced, that the caliper bushings & sleeves are replaced at the same time. The OE/production service pad kits were delivered with a package of new bushings & sleeves--this kit is available separately, or in equivalent form in the aftermarket. I cannot confirm whether they all use the same high-temp bushings as the GM kits below.

18008106 - BUSHING KIT, caliper, OE, all applications (one kit per car)
contains 8 bushings, 4 inner sleeves, and bushing lube
NOTE: PN change from 18005606

18034639 - HARDWARE (BUSHING) KIT, caliper, ACD Durastop, all applications (requires two kits per car)
contains 4 bushings, 2 inner sleeves, also includes inner pad clip, DOES NOT include lube

The caliper bolts are not included in production pad service kits, but they require inspection at the same time to ensure they are not grooved or that the plating is (not) compromised allowing corrosion to develop that will just grind away at the outer (small) bushings.

A proper lubricant is key--to provide actual lubrication over a wide temperature range, and to resist moisture intrusion and washout. Ceramlub & Pastelub (silicone based) meet these criteria and are not the problem, from my experience.

One thing you have to remember is that you relocated to a much harsher environment (TX to PA), especially the cold/wet season. GM's recommendation to service the bushings at pad change is a minimum, and I think you might want to try doing the bushing & lube service once per year--and use the OE high-temp orange silicone bushings.
In late August of 2009 I did a pad & rotor R&R job. At that time I did -not- replace the bushings and pins, just the Cermlub & Pastlub reasing. I did the latest swap (The 9C1 Rotors & calipers, and bearings) on to the Civilian last December. At that time I used the Cermalub & Pastlub.

You're doing the right thing--baseline the spec requirements--and let us know how it works out!
I was -surprised- because I did this lube process again as a CYA procedure, when I removed the rear snow tires and replaced with the all season tires for the summer. At that time, I took it upon myself to investigate the front end (brakes), and grease everything since I had the wheels off.

I can only -assume- that the remanufacturer's quality of parts are not equal to the OEM spec parts.

I will continue to do my bi-yearly grease job of the brake components and report back. I have recently bought a 4X4 truck, and the caprice will be off the road in just a few weeks, so the ONE winter it went thru (I was even laid off at the time and driving was at a minimum) shouldn't have had a great negative effect on the O-rings.
 

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The bushings Autozone and other companies supply calipers ARE GARBAGE... I used them for a year, Tossed them and bought some AC delco ones. The whole caliper is alot tighter. The auto zone supplied bushings and O rings diameter is too large + the o rings tear up fast.
 

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Discussion Starter · #10 ·
The bushings Autozone and other companies supply calipers ARE GARBAGE... I used them for a year, Tossed them and bought some AC delco ones. The whole caliper is alot tighter. The auto zone supplied bushings and O rings diameter is too large + the o rings tear up fast.
Thanks. That's the information I was originally looking for.

I've got the AC-DELCO stuff in the garage, and will install it this week when I get a free chance after work.

The auto zone supplied bushings and O rings diameter is too large + the o rings tear up fast.
That's exactly the problem I am experiencing. Not the piston boot, but the O-rings in the 'ears' seems to deteriorate rather quickly.
 

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Thanks. That's the information I was originally looking for.

I've got the AC-DELCO stuff in the garage, and will install it this week when I get a free chance after work.



That's exactly the problem I am experiencing. Not the piston boot, but the O-rings in the 'ears' seems to deteriorate rather quickly.
Yup! With heat they shrunk to nothing. The metal bushing just about fell out when I removed the caliper to change the brakes it was unacceptable! The small outside bushings were cracked up.. I replaced the 13 or so year old bushings on my impala years ago, they were STUCK in the caliper and took some time picking them out. . The autozone ones? Forget it! They fell out when I looked at it wrong. Probably Raybestos or Bendix supply the same kit to AC delco/ GM so if its cheaper, you might as well get that.
 

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Discussion Starter · #12 ·
Yup! With heat they shrunk to nothing. The metal bushing just about fell out when I removed the caliper to change the brakes it was unacceptable! The small outside bushings were cracked up.. I replaced the 13 or so year old bushings on my impala years ago, they were STUCK in the caliper and took some time picking them out. . The autozone ones? Forget it! They fell out when I looked at it wrong. Probably Raybestos or Bendix supply the same kit to AC delco/ GM so if its cheaper, you might as well get that.
Thru RockAuto (& the discount code listed in the MISC sticky)..The cost was only $3.07/Ea., plus I had to get some FT end rebuild components as well, so the cost was close to nothing.

"ACDELCO Part # 18K265 {#18034594, 18034639, 18K220} Contains the o-rings/sleeves for the attaching bolts, & anti-rattle clip for the inboard brake pad. Category: Caliper Repair Kit"

The problem I experienced was that the large O-ring was really torn up, and the bushing was practically seized in the O-Ring, not allowing aly movement whatsoever. I had a helluva time putting it back together, 'till I could get the replacement parts. The bushings didn't wanna pass thru the O-rings since they were so torn up.
 

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Guess I'll be buying the GM kit for the next pad job.

Just went into my calipers as I was getting an odd rubbing sound on my front right.

Damn if the slop caused by my badly flattened o-rings hadn't caused my PINS to snap! Didn't seem to affect the braking, but DAMN! Replaced the pins and the o-rings on both sides (they were flattened/loose on the driver's side too) and everything seems OK now.

Pretty sure that the o-rings that were in there were the ones that came with the Fleetwood Calipers, though. Wouldn't have expected them to be compromised so quickly.
 

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while we're talking about caliper service - I just disassembled a front caliper on my '95 9C1 which I believe to be original. I pressed the piston back in and noticed a bulge in the dust seal. Turns out that it was fluid trapped behind the dust seal. Looks like it got past the piston seal! At 160k, it's time for new (or rebuilt) calipers.
 

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Scott,

Pictures?

Can you measure the bolts that broke?

Did you compare the length of the broken bolts and the replacements?

What color were the bushings (O-rings) in the calipers? The cross-section shape of these bushings ARE "flattened", FYI.

Most unusual for these bolts to break--something is hinky here....keep digging!

http://www.impalassforum.com/vBulletin/showthread.php?t=227232

LONG - FOR WIDE CALIPER
18020239 - BOLT, caliper, OE, JA9 on 9C1, JM4 on 1A2 and 9C6 vehicles (discontinued, remaining OE stock held by VPI )
18034582 - BOLT, caliper, ACD Durastop - contains 2 bolts in package <<< This bolt or it's equivalent is what should be used with the WIDE caliper on HD12 brakes
(measures 4.37" overall, 3.95" underhead) - extra length corresponds approximately with caliper body width difference, 3.95" vs 3.72" = 0.23"

BOLT,FRT BRK CLPR(7/16X20X4.52)(ACDelco #18K208)(DURASTOP)

SHORT - FOR NARROW CALIPER
18022601 - BOLT, caliper, OE, JB9/JM4 on all other vehicles except above (measures 4.135" overall, 3.72" underhead--as below)
18034593 - BOLT, caliper, ACD Durastop - contains 2 bolts in package

BOLT,FRT BRK CLPR(HEX SOC 7/16-20 UNF X 3.72,.93 THD, GM300 8.1)(COATED)(ACDelco #179-1304)

18008106 - BUSHING KIT, caliper, OE, all applications (one kit per car)
contains 8 bushings, 4 inner sleeves, and bushing lube
NOTE: PN change from 18005606
 

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Should've taken pics.

The bushings were black, appeared to be flat (square in cross-section as opposed to round, as most "o" rings are) and seemed to allow for more play than I'd expect.

Thanks for the part #'s. I'll check on both them and the bolt lengths.

-Scott
 

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As several comments in this thread attest, the "reman grade" bushings (O-rings) do seem to be under-performing.

The GM parts are orange hi-temp silicone. Good lubricant is important too.

Bushing kit--optional, for one caliper, no lube included:
 

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Use the AC Delco Orange bushings. I have tried several of the auto parts stores brands and none of them can take a punishing like the Orange ones from AC Delco. The black rubber bushings become mush after a single driving event(Autocross or Road Racing) and must be changed. The Orange Bushings have survived several events. I purchased new calipers for my Impala when I installed the HD12 kit and still have the original orange bushings installed. Of course I take apart the brakes twice a year for inspections and cleaning.

Do yourself a favor and spend the little extra on the Orange bushings.

Later,
Michael
 
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