1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

rear drum brake cylinders interchangeable?

Old 04-14-24, 11:19 PM
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acdelco d1906 Nkg 49034

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Exclamation rear drum brake cylinders interchangeable?

One of the rear brake cylinders us leaking, I forgot which one. To save me the work of hauling a 40 lb jack down 2 flights of stairs, jacking up the car, getting the jack stands.......

Rock auto has the retaining pins for a ridiculous price. Why can't nuts and bolts be used instead of retaining pins and springs for the rear drums ?

Rockauto doesn't have front disc brake pad quieting shims. Mine are super rusty, being 40 years old.

Old 04-15-24, 07:32 AM
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The cylinders are left and right side specific because the left one has 2 ports for brake lines and the right one has 1 for a bleeder screw.
Unless you were asking about differences between years, then I'm not sure but thought at least 81-85 were the same.
Old 04-15-24, 09:29 AM
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The pins and springs have to be used because of adjustment and e-brake. The brake shoes need to float.You can sometimes find seals to repair the cylinders. The seals are more like a cap.
Old 04-15-24, 09:52 AM
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the only difference i think is the thread pitch for the brake lines between the sa and fb. otherwise i'd say the ones for the fb will probably be the same. not sure of this retaining pin and springs ur speaking of, unless it's what keeps the shoes against the backing plate. the shoes need to move in and out so nuts/bolts wont work. the wheel cylinders mount to the backing plate by 2 10mm bolts.
Old 04-15-24, 10:35 AM
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acdelco d1906 Nkg 49034

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I meant to ask if L + R are inter changebable on FB ---> F@#! it ---> I will replace both.

Rebullding brake cylinders has never worked

Yup! Retaining pins and springs for the rear brake shoes. I need to check 0'Reily's or home depot (maybe hook up with a husband hunter while I'm there).

thank you everyone!





































Old 04-17-24, 06:04 PM
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Did you find the parts needed for the rear brakes? I have a 1981 drum rear axle with everything still attached sitting on the front lawn. (Upgraded to disc / LSD). I could remove parts and ship to you. No charge, just cover shipping.

Chris
Old 04-18-24, 01:10 AM
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acdelco d1906 Nkg 49034

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thankyou, but I'm good......was the conversion worth it?

it's supposed to rain this weekend, so I can't do em
Old 04-19-24, 07:02 AM
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Where are you getting your drum parts? I checked RA and they are sold out of the drum parts.
Old 04-19-24, 12:43 PM
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acdelco d1906 Nkg 49034

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just got ......wheel drum brake cylinders.....and the front inner seal....from RA

centric rear brake drums got in 2015 (yikes that almost a decade ago ! ) needed to be rounded out on a lathe, IMO centric's quality is abysmal

amazing how much the local parts store mark things up.....makes sense when they might sell a part an hour, and they have to cover wages, electricity, and store's rent.......I wonder how much they pay for the part?.....how much is it to operate an Autozone Store / hour ?
Old 04-19-24, 02:51 PM
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[QUOTE=midnight mechanic;12599901]thankyou, but I'm good......was the conversion worth it?

I honestly don't drive the car hard enough to know if the LSD and discs make a difference. Mainly did the swap 'cause I know from this forum that upgrading to the LSD disc rear is on the must do list for the base level car, and an axle popped up on Facebook within driving distance. Also did it because I do all my own work and wanted the challenge... Did suffer from scope creep as had to source / install new driveshaft, bearings,rotors, axles and brake boost splitter and had some issues with bad parts shipped from suppliers.

Maybe reward enough is noticing folks at car meets bend down and look at the rear axle / brakes through the wheels, A surprising amount of non RX7 drivers seem to know about the rear axle swap on slick top cars.

Chris
Old 05-07-24, 10:51 AM
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how can I tell if the bad right cylinder was OEM ?

Last edited by midnight mechanic; 05-07-24 at 07:26 PM.
Old 05-07-24, 04:20 PM
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Last edited by midnight mechanic; 05-07-24 at 07:22 PM.
Old 05-11-24, 04:58 PM
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Originally Posted by midnight mechanic
I meant to ask if L + R are inter changebable on FB ---> F@#! it ---> I will replace both.

Rebullding brake cylinders has never worked

Yup! Retaining pins and springs for the rear brake shoes. I need to check 0'Reily's or home depot (maybe hook up with a husband hunter while I'm there).

thank you everyone!
FYI I got both sides new from Partsgeek cheap for my 79.

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