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Discussion Starter #1
Can someone please tell me which front pads and rotors fit a 94 Caprice with the LT1 and B4U tow package? I have been searching, googling, reading and emailing until I can't see straight.... I am so confused and frustrated! A friend told me he is running Powerstop z23 pad and rotors out but according to their site this won't fit my car.
Will brake parts for the SS fit?
 

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If you are NOT going to upgrade your brake calipers (not strictly needed), use the '7492-D614' front pad spec used by the 93 Caprice 9C1 and the 94-96 WX3 & WX8.
In other words, ask for the brake pads for a 94-96 ImpalaSS, they fit into your civilian Caprice's calipers (same as 93 9C1 calipers) just fine.
 

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Discussion Starter #3
Thank you. Do the rotors from a 94-96 SS also fit? Is it necessary to replace the ABS ring when changing rotors or can they be used?
 

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Yes. Every Custom Cruiser, Caprice, RoadMaster, and/or Fleetwood that is NOT a limousine uses the exact same front rotor, including Impalas SS and 9C1s.
If you ask for the front rotors for any of these vehicles (same rotor), the ABS tone ring will already be in place on the new rotor.

Buying drilled rotors is a BAD idea. Our rotors (front AND back) are barely large enough; drilling them removes mass from rotors that already don't have enough mass.
 

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You can also upgrade to the 9C1 calipers and install the thicker pads. I had the opposite happen on one of my 9C1s (a previous owner downgraded to the civvy calipers just on one side!) and I had a surprise when I went to install the OEM 9C1 pads that I had in stock. So I ended up replacing both calipers with the proper 9C1 version. It's always recommended to replace both side brake parts on the same axle at the same time but I guess the previous owner didn't get the memo.

The good news is that after you upgrade, both the civvy pads and the 9C1 pads should fit the bigger caliper because I think the only difference is the spread of the caliper to accommodate the thicker pads. I never tried this upgrade myself on a civvy car. But like I said, I saw the opposite happen, so that tells me the calipers are physically interchangeable if you are interested in using the thicker pads.

As others mentioned, rotors are the same. And they come with the ABS ring.
 

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Discussion Starter #6
Thanks for the info. There is so much that it borderlines on being too much
 

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Well then let's narrow it down to two options to save your sanity. I'm not sure if you have 11" drums with your car or not. If you don't have a 9C1, then the drums are usually the only way to tell the difference between HD or not. You might have HD if you have the tow package. If it came with them, who knows if the previous owner has retained the HD front calipers.

Either way, the HD stuff will fit a civvy car... so that's why I'm giving you two options below...

* All from Rock Auto *
Option 1: Just go with the POWER STOP KCOE2936 Stock Replacement Kit. Skip to bearings below.
Option 2: Retain existing configuration or upgrade to HD calipers which will allow you to use thicker pads:
CARDONE 184624HD
CARDONE 184625HD
CENTRIC 90862070 Select Pack Front Rotors and Semi-Metallic pads

Some people prefer ceramic pads these days. I run 9C1 cars and I've always been happy with Semi-Metallic performance (albeit more brake dust and more rotor wear, but good stopping power). If this concerns you, then you will have to pick out rotors and pads separately as I couldn't find a HD kit with ceramic pads (makes sense since Semi-Metallic was OEM on HD cars).

Don't forget bearings and grease, which are the same with both options above. The kits usually don't include these!
A3 x 2
A6 x 2
Seal 4739 x 2

On a 25 year old car, I'd also consider replacing the rubber lines if they haven't been replaced in a long time or if they look dry and cracked.
API 147417668 x 2
(and many others)

Don't forget brake fluid too! And consider a full bleed and fluid change if you haven't done that in a while. So buy at least 1 quart so you can pump all four corners until the fluid runs clean.

Hope this helps. And I hope others chime in if I got something wrong. Good luck!
 
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You can also upgrade to the 9C1 calipers and install the thicker pads. I had the opposite happen on one of my 9C1s (a previous owner downgraded to the civvy calipers just on one side!) and I had a surprise when I went to install the OEM 9C1 pads that I had in stock. So I ended up replacing both calipers with the proper 9C1 version. It's always recommended to replace both side brake parts on the same axle at the same time but I guess the previous owner didn't get the memo.

The good news is that after you upgrade, both the civvy pads and the 9C1 pads should fit the bigger caliper because I think the only difference is the spread of the caliper to accommodate the thicker pads. I never tried this upgrade myself on a civvy car. But like I said, I saw the opposite happen, so that tells me the calipers are physically interchangeable if you are interested in using the thicker pads.

As others mentioned, rotors are the same. And they come with the ABS ring.
Tom, my concern is the thinner D52 or Impala D614 pads combined with the wide-body caliper could reach a "maximum wear" condition that allows the front caliper piston to exceed travel limits and avtually come out of the caliper. This may be unfounded - in your case, no doubt, given the leve of maintenance you practice. The other consideration is that the use of 9C1 (JA9) calipers, with the "thin" pads on a non-9C1 vehicle is of concern, knowing the master cylinder displaces more fluid in the 9C1 version. Pedal travel exceeding normal in this situation would be an indicator of a parts mismatch or pad/rotor wear that the MC is incorrectly sized for.
 

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Hi Bill, yeah, I've never compared civvy and 9C1 pads side by side closely.

If I did have a set to compare, I'd look to see where the wear sensor is located... whether it would activate at the same pad depth? And the liner plate was same or similar thickness. If those dimensions are the same, then I think the civvy pads in a 9C1/HD caliper would still be safe then, correct? Assuming you stick to the same liner type (ie: semi-metallic) and you won't be using the car for either 9C1 or towing. All things being equal, you definitely wouldn't get the same life out of them.

As for MC bore size matching the calipers... you are on to something there. But there are overlaps depending on options, civvy, or not.

Let me look at a really old GM parts list...

Yep, it's a big list of RPOs and options that define which MC is used. And some PNs do overlap.

Normally I would think that rear drum versus disc would require different MCs, but looking at GM parts lists, that's not the case. They overlap MC part number between disc and drum applications. I remember this being discussed many years ago (which is why the Impala SS rear disc brakes are lethargic, they use the same proportioning/balance configuration as the drums, which is great for the lawyers but not great for performance, thus the "stealth bolt" mod was born).

What I did find is that '94 oddly has different PNs for MC. And no matter what options you have, they were all 1.25" in '94. Whereas 95-96 overlap with various sizes listed below. I don't have time right now to give it a deep study...but...

1.25"
21mm
28.6mm
40mm

This is odd... depending on options, they show:
'94 shows 1.25"
'95 shows 21mm
'96 shows 1.25"

That leads me to wonder if 21mm is a typo since 1.25" is about 31mm (perhaps they meant 31mm and the author/editor screwed up). And '95 and '96 both use PN 18030951 MC service kits that include all of the moving parts (including the piston). So WTF. Has to be a typo.

Anyways, you bring up good points! So without empirical evidence to ensure safety, I retract my recommendation to upgrade a civvy car to 9C1/HD calipers without doing your homework to ensure that the MC would work properly with the 9C1/HD calipers as well. Just because I know it can be done, doesn't mean it should be done.
 
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