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Discussion Starter #1
I was just wondering what would cause a richmond pinion gear to snap clean in half and an Eaton Posi carrier to just crumble into pieces??? I was giving a person a ride in my car. 1st gear I got on it. The tires just spun, so there wasn't that much stress on the rear end. I hit second gear... POW!! SMASH< BANG GRIND!!!(*^&*$*^&*%$#@!!!!!!
I opened up the rear end the nex day to see lots of little pieces of scrap metal everywhere!!! I Also had a $140 aluminum rear end support cover that was busted...so that big POW just threw over $800 down the drain...

Im lucky I have a disc brake conversion cuz I can just see my axles wobbling out from under the car...

Can someone please give me an explanation???

P.S. Does anyone have a 8.2 carrier with gear they want to get rid of reall cheap... I need something in there for now just to get around, It is my daily driver... HELP!!!:confused: :confused: :smash:
 

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Well, since both units failed at the same time on such a large scale, it seems to me that they were subjected to forces from directions and in places that they were not designed to take. I would bet that they were not installed correctly. Did you check the clearances and shim properly? Were all bearings pressed on properly and operating smoothly? Did you wrench down the main cap support screws on the girdle cover with all you're worth, by any chance? Really. For a failure such as this something was seriously out of whack.

Sucks, though. That's a lot of money.
 

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current hot rod: CTS-V
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What kind of power were you pushing through that rear? How long ago were the parts put in?


It's got to be an installation error, or a manufacturing flaw.
 

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8.2" rear ends are not very strong to begin with. If it has been hammered on for a while that means it's that much weaker. Once a part breaks inside the rear end, that led to other things breaking as well. It did not all explode at one time. You probably broke the carrier and when it got hung up the pinion snapped (or the other way around). If you are making decent power it was just a matter of time before it let go. They can be made a bit stronger but, for the money I would HIGHLY suggest going with a 8.5" 10 bolt. What year Camaro? What engine/power?

Royce
 

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Discussion Starter #5
Its a 1969 Camaro, supercharged 383ci. I've never had it dynoed but my guess is some where around 500hp. I drove it down to Florida from Connecticut Thanksgiving weekend. Right before I brought it down, I went throught the whole car. I popped the cover off and retorqued everything to spec. The support cover recommends 10 ft lbs for the support screws, and that is what it was torqued to. I had been driving the car around since august when I finished restoring it. I had the rear end put together by a teacher at a Mechanics School. He measured the pinion depth and backlash and I would think that he would know what he was doing. He was a highly certified mechanic, from what I've heard. It always had a little bit of a whine at higher speeds though. I drove to Florida with no problems and I had been driving it ever since every day. I haven't been to hard on it, the only reason I was really getting on it was to show off the power to one of my buddies down here. I was planning on bringing it to the track this Wed, I wouldn't be supprised if this happened on a sticky surface and with a hard launch, but the tires were just spinning. The carrier was not stock eather, I spent about $450 on this EATON unit w/ Quote "high strength casing" in the description of the part! I still can't believe how clean the snap was on the richmond pinion gear... those gears are suppose to be high strength harded heat treated.......:boxing: its not suppose to break like that. Its very frustrating. I think its time for a 9" or a 12 bolt or maybe that 8.5. Are they really much stronger?? I think this is the 4th or 5th time this rear end has broke on me and I've owned the car for 4 years.. Im starting to lose count.
 

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For the money, the Ford 9, the GM 8.5 AND the 12-bolt will roughly cost you almost exactly the same.

Since you already have the disc brake kit, and complete axle housing for your 8.2, you are one step ahead on rebuilding the one you have, but would be in the same boat again since you are evidently overpowering the limitations of the 8.2.

Sell the disc brake kit, the housing, and if the axleshafts are still decent throw them into the deal with the housing, and get one of the others mentioned above.
 

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"supercharged 383ci"

Scratch my last post, because I think I know your problem - too much torque! In fact, scratch that too. Your rearend was just not worthy of such a beast. Seriously.

Sure, spinning skinny tires (were they skinny?) is easier on a rear end than hooking slicks, but the fact remains that you were putting FULL torque from a BLOWN 383 through this 8.2." The fact that the tires had no traction is almost irrelevent when we're dealing with the amount of torque your motor makes. You say you never dyno tested it. Well, you could have been putting 600+ ft-lbs through that thing!

Oh yeah, I wouldn't doubt that your gears or posi had a small flaw of some sort that would nomally go unnoticed or something... I say get a worthy 9" behind that blown beast.
 

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whoa supercharged 383. There's you problem. That 8.2 was a time bomb.

you can buy brand new 12bolts/9inches/Dana 60s for your car.
 

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Discussion Starter #9
Well, the tires aren't very skinny. They are pirelli 315/35/17's, and these tires are horrible compared to the 315/35/17 nitto drag ratials... those tires would hook right up once they were warm. I think I will invest into a better rear.
 

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Whoa, 315 tires, blown 383, and an 8.2" rear. That combo was never meant to be. The very large amount of kinetic friction between the huge spinning tires and the pavement was what did your differential in. Power those tires with a blown 383 and you should have expected this.

Get a good rear, and then watch out if it ever hooks. Have you done anything to the chassis? A stock Camaro unibody, even with subframe connectors, won't take that kind of abuse (hooking 315s with 600 ft-lbs) for long. I think you need some kind of roll cage.

If you're worried about it, I'll trade you my 406 for your 383. :thumbup:
 

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Post some pics of the car and the axel. We like to see blowers and the resulting broken stuff from american iron, once again, doing its job a little too well (which is something that I cannot be accused of, here at work today...).

We need pix. :D Uhh, you know, to address your question and whatnot...

Running a weak rear is one of the biggest mistakes somebody can make, in all seriousness. Nothing is going to send you out of control faster than a rear letting loose on you. Go back through your car, you need probably more trans and subframe connectors before you go any further. Fast cars don't mean crap when they're upside-down in a ditch because the owner was a little cheap and didn't think he needed some good quality parts.

Live and learn, glad you're ok-

K
 

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Discussion Starter #12
I wonder why some people assume things... I didn't just drop this engine into a stock 69 Camaro. I spent all winter restoring and strengthening this car to handle such power. I wasn't aware that the 8.2 rear end was a weak rear. I will take some pics today of it and hopefully have them posted tonight. I have all poly pushings throughout the whole car, competition engineering subframe connectors, competition engineering 8 pt. roll cage, Latterbars in the rear which are mounted to the subframe connectors and to where the tubes of the roll cage are welded to the floor, so alot of the torque is absorbed into the roll cage. I also have lift bars mounted to the axle and leaf springs for added strength. The whole front clip is fiberglass, so the car is lightened alot. I'll let the pictures say the rest when they are posted. I already have a 400 small block sitting im my garage... thanks for the offer though. Thanks for all the replys. They are greatly appreciated. I hate it when this kind of stuff happens though... but im living and im learning, for sure. :drunk:
 

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Discussion Starter #13
Here are some pictures. I didn't want to get back on the ground and get all greasy again, so I didn't get any pictures of the insides of the rear end, but I did get a shot of a few pieces that use to be the carrier and the nice clean snap of the pinion gear. The guy that painted my car oversprayed onto the ladder bars and sub frame connectors:mad: . The car is an everyday driver so, everything isn't perfectly clean.
 

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