383 Power

iTrader: (2)

Just found a 342 Posi Rear End with Disc Brakes from an 85 Firebird Formula. This seems a little much to be stock. It's a 9 Bolt cover. The Torque Arm DID bolt right too it though, so it looks like it COULD be stock. If it is, i would imagine that it's pretty uncommon. I'm pretty sure this will bolt right up to my 1982 Camaro. I had to cut one side of the E-Brake cable. Do they make some nice aftermarket replacements?

BTW, I traded a 600 CFM holley, A Mechanical Speedometer, and $100 Cash for the Rear End.

The Guy still has a 5 Speed Transmission he's trying to sell and the T-Tops look like they're plexiglass.

//<86TA>\\

iTrader: (14)

if it has the torque arm mount, its a stock rear. Its a 9 bolt, probably the crappy delco iron discs that are pretty much worthless, its not a 3:42, its either a 3:27 or maybe a 3:45, ( unless he lied, then who know what it is) you should pull the cover and see what it is and if its even a posi.

not very uncommon at all.

383 Power

iTrader: (2)

It's a Posi. I pulled it myself. While it was in the air i spun a tire and the other one went in the same direction. I marked the tire and spun it while watching the Knuckle thing. It went about 3 1/2 times around, so I believe the ratio. If the discs are ****, i can just pull em and replace. I'm just happy to get the right size axle with Posi and Discs.

//<86TA>\\

iTrader: (14)

brakes should be pretty obvious, if they are iron calipers, they suck, if they are the aluminum pbr's they are better.

383 Power

iTrader: (2)

Wheels are still on the Axle. Just barely had time to remove the Axle. I'll investigate in the daylight and update.

383 Power

iTrader: (2)

I've been reading that these Posi's tend to slip after about 20,000 Miles. Do they make a Rebuild kit or is that just a Myth? Just how tough is this rear end?

//<86TA>\\

iTrader: (14)

posi last longer than that, but that doesnt mean your isnt shot.

just a little stronger than a 10 bolt, and harder to find parts for

autotec101

First off, iron disks maybe are not the best gm ever made but they are far from junk....still way better than drums. Second I picked up a 3.23 posi/disk, for 200.00 and it bolted right up, however the e-brake cables were another story. I could not find the correct ones and ended up modifing drum cables, I had to cut and weld new ends on but been a year and they still work awesome.I also stipped it down and did a complete overhaul on it, but did not have to replace the slip disks, they were like new still.

//<86TA>\\

iTrader: (14)

hahahahaha, seriously, i can bet you quite confidently that 90 percent of the 3rd gens out there with the iron rear calipers, have no functioning rear brakes. I would take my drums anyday over those POS things.

383 Power

iTrader: (2)

Are the emergency brake cables the same as for drum brakes?

Will 4th Gen Discs and Rotors fit on the axles?

Someone told me that i need special gear oil for it since it's a posi. What do i get?

JamesC

iTrader: (5)

No.

There are two fourthgen braking systems: the 93-97 (LT1) and the 98+ (LS1). Your only choice is the former as the latter is designed for 10-bolts. You'll need the correct backing plates to accommodate the larger rotors and calipers (PBR's). Don't neglect the 1LE combination (though that may be a problem since your 82 would have SAE threads and 84 or so up are all metric) valve and speedo gears. Both backing plates, valve and parking brake cables can be purchased from Ed Miller:

http://www.flynbye.com/

Though I have no experience with 9-bolt limited slips, some members have claimed additive is needed, while others say no. A search might be beneficial.

JamesC

383 Power

iTrader: (2)

Thank you, i understand about the Proportioning Valve and Speedo Gears. Right now my Speedo is wrong, but i know how wrong it is since i have a speedometer on my Phone. I'm planning on rebuilding the Tranny. When i do, the speedo gear will be involved. How complicated is the inside of the Differential? I would assume that it's less complicated than an open or a Posi. I have to remove the axles to get those backing plates, right?

JamesC

iTrader: (5)

Note my edit above especially about your 82 valve.

I'm not sure I understand your question. There are only two possibilities: open or limited slip (aka posi). The axles will have to be removed.

JamesC

383 Power

iTrader: (2)

I goofed on the Communication side. What i meant was Open or Locker.

Hopefully i can get this to work out. I suppose i could change the Master Cylinder if that's what you mean would have the wrong threads.

JamesC

iTrader: (5)

The master is fine for either drums or discs. The combination valve in your car, if it's the old cast iron type, will have SAE threads and as a consequence be problematic as the newer valves have metric threads. There is, however, the after market adjustable route to consider.

JamesC

383 Power

iTrader: (2)

Thank you. I'll check into that. One thing that I do have is time. I would be fooling myself if i said that i was patient, but i know that I have to be. One step at a time. This isn't my Daily Driver. I just hope i don't mess anything up while removing the axles. it would be easy to do research on a 10 bolt since they're everywhere, but the 9 Bolt is completely different.

383 Power

iTrader: (2)

If i understand correctly, i can remove the axles without disturbing the pumpkin. It would appear that they're held in with "plates on the outside of the housing". If this is true, does this mean that i can change the brake's backing plate and replace the axles without getting into the gears?

autotec101

you will need to remove the cover and the center pin in the housing. then push the axles in a touch to remove a c-clip that holds the axles in. This will in no way affect, change or alter the gear set up. install in the reverse manner

autotec101

and yes you should add the posi additive when you refill, or you will end up with a chatter sound from the clutch disks when cornering. even if some apps may not require it 90% do and it wont hurt anything.

383 Power

iTrader: (2)

I thought that the BW 9 Bolt axles were BOLTED on, not C-Clipped. I'm actually pretty Intimidated. Will a 4th gen backing plate for Disc Brakes bolt up?

autotec101

sorry my mistake, I was refering to the 10 bolt

JamesC

iTrader: (5)

No, the fourthgen plates are designed for 10-bolts (the last 9-bolt was in 89).

JamesC

383 Power

iTrader: (2)

Thank you JamesC

383 Power

iTrader: (2)

I found a place that offers replacement E-Brake cables for the BW 9 Bolt:

http://www.rockauto.com/

The parts Numbers are as Follows:
Right Rear Cable C1345
Left Rear Cable C1205

383 Power

iTrader: (2)

This is my Baby! Isn't she Gorgeous!

The tag only says that it's limited slip.

where can i find the serial numbers that will tell me more?

Where are the bolts that hold in the axles?

The Guy said it's been sitting since 1992. I'm guessing that i should replace the seals. How hard is that to do? Will i need special tools?

383 Power

iTrader: (2)

If i get a 4th gen rear with traction control, do i have to hook it up?

383 Power

iTrader: (2)

Can i use silicone to seal up my Differential after i change the oil, or do i need the gasket? I bought Valvoline 80W-90 and it says that it's Synthetic. It also says Limited Slip. Should this be enough, or do i still need an Additive?

//<86TA>\\

iTrader: (14)

you can use RTV silicon. You have to partially tighten the bolt, let it cure for 12-24 hours ( should say on the package), then final torque the bolts.

383 Power

iTrader: (2)

Alright, i have a few more questions. I don't think these have been asked (At least Recently).

In the Pics below, there's some kind of valve thing. It appears to be leaking. What is this for and can i remove it?

The other pic has the Traction Control hookup. Can i remove and plug this hole?

383 Power

iTrader: (2)

Sorry, i had forgotten to load the pics

JamesC

iTrader: (5)

Vent. No.

JamesC

383 Power

iTrader: (2)

Please tell me this isn't my fill hole on this differential. It leaks, and i can't find another rubber plug for it. I thought i might just get another Cover, but the one i got, doesn't have that hole in it. is there another hole that i can use to fill the Differential?

//<86TA>\\

iTrader: (14)

since its on the bottom, i dont think its a fill plug

looks like a hokey added drain plug? weld it shut, or weld a thread bung to it to keep it as a drain. Or just get a new cover. You should be taking it off and changing the oil anyway

383 Power

iTrader: (2)

If that's on the bottom, and it's not stock, Where's the Fill hole? Do i remove the vent to fill it? I don't remember seeing a fill plug anywhere. I have a brand new cover, but that cover doesn't have a hole at all (Except the bolt holes). My intention was to change the fluid, but how would i have done it if it was still on the car? There's got to be something hidden under some grime or rust.

383 Power

iTrader: (2)

I found it!! It was under a whole crapload of crud. The reason i didn't see it under the crud is because where you put the wrench on it is female. I feel better now. Now the only thing i'm worried about is that damn plastic/rubber plug. if it's leaking now, did they run the thing with it leaking like that? Is there enough fluid in there? As soon as i'm done cleaning the case, i'll pop it open and find out how much is left. Right now it's sitting on jackstands with the pinion down. It can't leak out of that plug this way.

matt91rs

that rubber plug means that axle came from pick-n-pull they punch a hole to drain it faster than pulling the cover
throw a new cover on it and your set.

383 Power

iTrader: (2)

You're AWESOME. Thanks for setting my mind at ease. I do hope you're right. I DID pull this myself from a U-Auto-Pull-It (Pipes) in Shreveport. If they drilled that hole, i hope they were careful and didn't drill into the Ring Gear or Carrier. Went there one day and they had a 4th gen on the rack getting it ready. I asked if it had a plastic gas tank and the guy said it did. The unfortunate part of that is that he couldn't sell it to me. He had to cut it.

383 Power

iTrader: (2)

I have confirmed that the plug was indeed put there by the junkyard. I went there today and looked at alot of other diffentials and they all had the same plug. I also asked and the guy said that they did it. That makes me feel better. I have the Axle/Differential Cleaned, Sanded, and Painted now. I'm ready to Drain what's left of the oil, Refill it, and install the new cover ($11.99 at Napa). I have the axle sitting on jackstands with the pinion pointing down. Once i Drain the oil, i intend to put it into this position and just pour the Fluid directly into the differential. Then i'll use some Sealant and bolt the cover on. The only thing that i'm worried about is Fluid leaking from the vent. In this inverted position, what do you guys think? Will it leak out of the vent?

JamesC

iTrader: (5)

Use the fill plug hole (pinion level). Fill until gear fluid dribbles out to ensure you've used the proper amount of fluid.

JamesC

383 Power

iTrader: (2)

Thank you. I didn't think about that. I am so glad i have someone to bother with all of my questions. This whole process is an adventure. Once i fill it to the appropriate level, can i put it back in the pinion down position safely and not have the oil drip out of the vent?

383 Power

iTrader: (2)

Well, i opened it up, scraped off the old Gasket, and Put on the new cover. The old one, as you can see, has been vandalized by the Junkyard. From what i could tell, the gears looked REALLY good. I'm pleased to see that. The magnet had SOME metal shavings, but i think that's normal. Didn't look like too many.

Heh, and those are my Comfy Junkyard/Tinkering Shoes too.

//<86TA>\\

iTrader: (14)

that plastic thing that leaking is the vent, you can get new ones, but you probaly dont need it.

with the pinion facing down like in your pics, the oil wont leak out the vent because the rear doesnt have that much oil in it, and what there will all be sitting down with the pinion. You have to fill the rear with it sitting like it would be in the car, or even better, installed int he car. then just fill it through the hole in the passengerside, that has the square drive in it, till the oil starts to run out, and thats it.

did you put rtv on the cover before you installed it? you didnt use a paper gasket did you?

383 Power

iTrader: (2)

Yeah, i used the Paper Gasket. Do i need to do it over again?

Well, it's an easy fix. I'll redo it.

//<86TA>\\

iTrader: (14)

they almost always leak, i always use rtv instead.

fireburdluvr85

thats not a 9 bolt. im lost here as the first few post talked of a 9 bolt then a 4th gen rear. seeing as you show a pic of a speed sensor im thinking now you have a 10 bolt?

383 Power

iTrader: (2)

I have both now. I started with the 9 bolt and then found a 10 bolt. Since the 10 Bolts are more common and easier to get parts for, i switched to using that. I still have the 9 Bolt though.