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I'm considering buying the rear end out of an 84 firebird with the L69 motor. The tech data page says that 84 firebirds with the automatics came with the 3.42 but a few people posting on the forums claim theirs came with the 3.73. Does anyone know for sure one way or another? Also where these limited slip rear ends?
The tech data page says that 84 firebirds with the automatics came with the 3.42 but a few people posting on the forums claim theirs came with the 3.73.
This far out, who knows what's in the car. My IROC was supposed to be equipped with 3.23.s and discs but, well, nooope. Best drop the cover and check. A visual will answer all your questions. The FAQ sticky concerning 10-bolt may be of help. Best of luck.
Could be either a 9 bolt Aussie or a 10 bolt GM corp. rear.
(Depending on year)
The HO advertising/description mentions a 3:73 ratio.
But if its a Aussie 9 bolt I suppose its a 3:70.
If its a GM 10 bolt its a 3:73
(IN MOST cases and depending on year)
UNLESS somebody checked off the wrong box on the dealer
order sheet!
Same deal with the posi aka limited slip.
Best way is to see if the car is a L-69 HO.
If the rear is out and on the floor just turn the shaft yoke or
axle and see if both wheels turn at the same time.
Either get the rear code off the axle tube and check the book
for posi, ratio OR
Count the number of times the yoke turns and the axle/wheel
turns and do the figuring.
That will give you the rough ratio numbers.
Decoding the axle tube numbers is the most accurate.
Won't be a 9-bolt, if original; that rear was introduced later. No "features from the future".
Which "original" of course, is not necessarily the same thing as WHAT'S IN IT NOW.
Most 84 L69 auto cars got 3.42, but some got the real-deal 3.73s. Only way to know for sure is to look. Which, since you're "considering buying", you'll be doing anyway, not only for parts identification but also to check its condition; posting here is mostly a waste of time since YOU'LL be seeing inside it and WE can't.
Same for posi. Same for disc brakes. What you SEE is what it IS. LOOK LOOK LOOK LOOK LOOK LOOK LOOK.
SOFA.........I have a late build 84 with a 9 bolt.
Figured the ratio to be a 3:70 and its a Lim slip.
All original car.
Looks like its never been changed out even tho 9bolt.com
sez it was in the t/a from 83 and the Z from 86.
So who knows...........late build/used what rear was handy
when it rolled down the line etc.
From 9bolt.com:
The 9 bolt GM Borg Warner is an Australian rear that was used in Camaros from 1986-93, Firebirds from 1985-93, and Trans-Ams from 1983-93. This rear was a factory performance upgrade and is much stronger than the 10 bolt.
Hopefully the OP will find a nice LS 10 bolt with 3:73s at a good price.
9 bolt parts are $pendy!
My 84 L69 has the original rear with the stock 3.73 gears (5 Speed) and gov lock posi.
I always wondered why they put that piece of crap carrier in there. I have only seen it in 84's.
The easy way to tell is to look at the punkin cover.
A 9 bolt had a rubber plug in the cover near the top.
The 10 bolt has the 3/8 plug in the side of the yoke.
If a rear has a Gov-Lock in it, it won't be a 9-bolt.
The OP's potential purchase won't be influenced by what any of us out here do, say, "know", or have. It'll be whatever it is, and he'll know what that is when he LOOKS AT IT. Meanwhile, any arguments we have out here are merely verbal self-pleasure.
NO matter if its a 9 bolt or 10 bolt and it may have a Gov-loc/posi/
limited slip !
Just turn the driveshaft yoke and if BOTH wheels turn at the same
time then its a gov-loc/posi/lim. slip
BUY IT!!!!!!!!!!!
Thanks for all the replies! I plan to take a look at the rear for myself but didn't want to drive that far if it wasn't likely to be what I needed. I think 3:73 might be too much for my 5.0 TPI, I'm hoping to find a 3:42 with a gov lock or limited slip.
I thought it was the other way around, that if its spinning on wet pavement then hits a dry spot the rear could grenade. Do I have that right? I don't ever drive it in the rain or intentionally burn out anyways. The worst the rear would see from me an occasional hard launch with the best a stock 305 can muster up
Dunno. Mine hooks up both wheels effortlessly in the wet with the 3.73's. I have more traction than horsepower so i try to be gentil with it in the dry.
I do a burn out when I want wet or dry and don't worry about it!
At 170k miles I don't worry about it !
Also my gov bomb equipped 72 Pontiac or my EIGHT GM trucks
that were WORKED hard towing or snowplowing!
I LAUGH at the fools here and the truck forums that carry on about how
weak/crappy/yada yada the gov-bomb rear is!
These cars don't have enuff power to explode them!
(except under severe abuse of course)
I'll challenge - once again - you to provide some kind of evidence of your insistence that the 9-bolt was factory installed in your 84...........
So; Now I'm curious again, You say that you've got a window sticker from your 84Z showing a 9-bolt ?? ( What exactly is your center console RPO sheet "Gxx" code? ) You never sent your window sticker too me,....... & I'm sure I've never seen it posted here. Now THAT is something I would remember !!
Here's YOUR opportunity to "school" me,..... Let's see your 1984Z with factory installed 9-bolt window sticker.
PUT UP or SHUT UP.
The Gov-Loc was the ONLY POSI offer in the 84 Camaros and it is widely know to be junk. There was also a POSI shortage in 84 so it's probable that the facotry 3.73 isn't POSI. My step-father has an 84 3.73 Gov-loc POSI in his 86 and it works fine,... but I - and just about anyone else who knows anything about rear ends - would NEVER recommend that someone buy it as an "Upgrade."
YEA YEA.......
Your the SAME j*rkoff that gave me a hard time in the l-69 forum!
I posted the FACTS from 9 bolt .com that certain 84s had the 9 bolt.
One post claims the 9 bolt is stronger than the GM 10 bolt and another
claims its junk.
But YOUR the EXPERT in your SMALL mind!
I do have a yellow build sheet with the codes.
BTW: limited slip, gov-loc, posi all names generally used to describe the
SAME thing!
But you wanna be a azzhat and split hairs!
So I figured I would bust your b*lls and NOT post the sheet or my G code
so you would BLABBER on and ON like you did in the L-69 thread............
So I figured I would bust your b*lls and NOT post the sheet or my G code
Ya'.... you really showed me didn't you. I'll be sure to add my 2-cent's into any/every post where you claim to have a "stock installed' 9-bolt in you 84 till I'm proven wrong. I think that people knowingly spreading false info is a real drag and any will continue so that less knowledgeable members don't accept that bullshit for accurate info.
You've got the RPO sheet - but don't want to post it so you can bust my *****,...... Understand that it just makes you look like you know that your 9-bolt claim is a lie.
Not like I've never been wrong before - or having a problem admitting when I'm wrong - so grab hold of your nut-sack and post the RPO sheet from your glove-box.
Just to be sure that you have at least a limited understanding on what your talking about; Gov Lock, Auburn, and Eaton are all POSI ( AKA "limited slip" ,..... ) and none of them are the same.
I'm considering buying the rear end out of an 84 firebird with the L69 motor. The tech data page says that 84 firebirds with the automatics came with the 3.42 but a few people posting on the forums claim theirs came with the 3.73. Does anyone know for sure one way or another? Also where these limited slip rear ends?
The Best Way,Find The Rear Axle Code On The Axle Tube It's Most Likely Rusted Over And Difficult To See,But It's There.
Just to be sure that you have at least a limited understanding on what your talking about; Gov Lock, Auburn, and Eaton are all POSI ( AKA "limited slip" ,..... ) and none of them are the same.(QUOTE)
HeY azzhat
Since you can't READ and MISSED the WORDS:
BTW: limited slip, gov-loc, posi all names generally used to describe the
SAME thing!
DID YOU MISS THE WORDS "GENERALLY USED TO DESCRIBE"?
All this is REALLY helping out the guy thinking about buying that 10-bolt wanting to know what gears are in it... thanks all. Good job.
I thought my Advise to ZsTransAm about the 84 rear he's checking out was pretty clear.
Originally Posted by Johninri
The Gov-Loc was the ONLY POSI offer in the 84 Camaros and it is widely know to be junk. There was also a POSI shortage in 84 so it's probable that the facotry 3.73 isn't POSI. My step-father has an 84 3.73 Gov-loc POSI in his 86 and it works fine,... but I - and just about anyone else who knows anything about rear ends - would NEVER recommend that someone buy it as an "Upgrade."
I could be wrong,...... maybe he should listen to this guy:
Originally Posted by sonjaab
I LAUGH at the fools here and the truck forums that carry on about how weak/crappy/yada yada the gov-bomb rear is!
Yeah it started out pretty clear until you fell for the flame bait.
We used to have a saying; "never argue with an idiot, a bystander can't tell which one is which". That guy .... doesn't need to be argued with, he can just post that worthless egotistical crap into a vacuum as far as I'm concerned. If we all ignore him maybe he'll go away. (we can hope, but hope isn't a very effective business plan I know)
And, for the record, all that crap about tags and codes and stampings and all that crap is just that, CRAP... if you look under my 83 L69 car, there's a 91-92 rear with PBR brakes, 3.73 gears (which were stock for the car but not the rear), and an Eaton (NOT Grenade-Lock) posi. The codes more than likely don't agree with the REALITY, so if I junked my car and somebody bought the rear and ran the "codes", they'd probably come and post on here all about "they had yadda yadda yadda in 83, I've got one..." just like that other yutz. But I guess I just clean forgot to change the codes. Shame on me. I've been meaning to procrastinate that but just haven't got around to it yet.
In some states, an early 85 gets titled by production date as an 84.
There; I was able to come up with an explanation for the idiocy that precedes this post.
Never seen or heard of that... in every US state I know of, which admittedly is only 50, (maybe there's more somewhere?) VIN E = 84, VIN F = 85. Production date isn't even a factor, they don't even bother to look it up even if there's a way they could, they just go by the VIN. Butt hay, maybe there's some state out there somewhere that doesn't follow the "rules"; been known to happen in other areas of interest.
A yutz is still a yutz. What was that old t-shirt you used to could get... "I may be fat, but you're UGLY, and I can go on a diet" You can't fix stup.... Ooooppps, can't say that in 2016 anymore.
Last edited by sofakingdom; 06-26-2016 at 04:39 PM.
No factory installed L69 Camaro EVER got a factory installed BW rear end - period.
Originally Posted by jmd
In some states, an early 85 gets titled by production date as an 84. There; I was able to come up with an explanation for the idiocy that precedes this post.
So; your take on this is that somehow a "factory 3.70 9-Bolt" got installed into this dudes 84Z in early 85 ? You might remember that in 85 GM changed EVERY Chevy F-Body rear gear set from a 7.5" to a 7 5/8", Yet somehow think that only Sonjaab's 84Z got a 7.75" because in early 1985......"
Originally Posted by sonjaab
......who knows...........late build/used what rear was handy when it rolled down the line etc. "
Ya',... Sure; cause GM just tossed what-ever rear end was handy into cars as they rolled down the production line. Idiocy ----> Exactly what I was thinking. Only an idiot would have-but-hide the RPO sheet showing the gear code + VIN and proving that his car is a 1-of-a-kind.
"never argue with an idiot, a bystander can't tell which one is which".
Good Point Sofa, but some members might not know better and might actually believe that his claim is accurate. Can you imagine if I posted into the "General Engine" forum that I had an 84Z with a factory installed 350ci ?? His claim is equally ridiculous as my example because both the 350ci and the BW rear-end were FIRST offered in Z28 starting in 87, a full 3 years after his car left the factory. ( not counting any 1986 'test cars" that existed. ) When he keeps posting that nonsense - and I read it - I will continue to 'call him out' on it. Once he posts a pic of the RPO sheet that he says he has,...... I'll shut-up about it and I will still - honestly - be glad to have learned about a real/true 1-of-a-kind Thirdgen.
No hiding..................
Just bustin' on a azzhat!
No need to PROVE anything to the 2 resident "experts" postin' here.
I just posted the info. for the OP to identify a replacement rear end
for his car.
Was it incorrect?
Prob. not but you came in bustin' ***** about my rear end.
SAME deal you did in the L-69 forum!
Adding your worthless 2 cents there also!
You "EXPERTS" IGNORED 9bolt.com (because you "experts" are smarter)
The 9 bolt GM Borg Warner is an Australian rear that was used in Camaros from 1986-93, Firebirds from 1985-93, and Trans-Ams from 1983-93. This rear was a factory performance upgrade and is much stronger than the 10 bolt.
This is my last post on this so you can blather on allyou want................
You are so helpful to this community!
So; your take on this is that somehow a "factory 3.70 9-Bolt" got installed into this dudes 84Z in early 85 ?
Not at all. I mis-spoke earlier. I shall re-state it.
In some states, a vehicle registered in 1984 was titled as an 84. You and I would look at the VIN and say it's absolutely an 85. GM would call it an 85 model year car.
I had a friend with a non-third-gen this happened to in Kentucky. I've seen that registration & VIN. There are other states it has happened in. It's probably a lot less common now. But it sure happened in the third gen era.
06-18-2016, 09:14 AM
What was that old t-shirt you used to could get... "I may be fat, but you're UGLY, and I can go on a diet" 
You can't fix stup.... Ooooppps, can't say that in 2016 anymore. 
Ya',... Sure; cause GM just tossed what-ever rear end was handy into cars as they rolled down the production line. Idiocy ----> Exactly what I was thinking. 