10 bolt bit the dust

[84HOtransam]

well after a year of abuse the junkyard posi carrier i put in my car finally died this weekend when i was home...i was pulling out of a parking spot and the car just shuttered and stopped..when i started going again i heard a chattering sound...i pulled the cover the next day and saw chuncks of spider gears.

i think im going to go straight for a 12 bolt so i wont have to worry about this problem again...

the car right now.. stock 3.73 posi disc rear with 96,000 miles and 26 spline axles..

its not daily driven (im at school and i just bought a blazer for a daily driver)

it wont be driven more then 3000 miles or so a year... it will see highway time on the way to the track..

what should i get in the 12 bolt..
i want at least 4.10 gears with an eaton posi

how many splines on the axles.

the car is just the 305 right now..but plans for a 355 or 383 in the future.

[bad64chevelle]

Yeah my 10 bolt is broken, and barely holding on to its last life. When I drive its a constant clunking noise, and when I launch the car hard i get a grinding noise. All this abuse and I cannot believe its still holding up! Once I find a 12 bolt, or whether or not I am keeping the car I will toss one in it. I have my eyes on another vehicle right now, so I hopefully wont have to deal with these 10 bolt woes.

[Batman]

What tranny you have? If it a 5 Spd go with 4.10's, if it is an A4 I would stick with 3.73's. I'd get the eaton Posi and go for the gusto with 33 spline axles, if you are gonna do it may as well do it right instead of looking down the road and saying " Boy I wish I'd.....". For the extra price it is a little more piece of mind. I don't think it will make THAT much of a difference between 30 and 33 spline, but just what I would do. I have the 33 spline in my T/A and with over 400HP on tap and slicks not some much as a grumble from the back. Also spring for the aluminum diff cover, helps alot with cooling at the track. Good luck and sorry to hear about the 10 bolt!

[SteveR]

If you go to Moser's website they have a calculator that will tell you what spline you'll need based on your setup.

[Fasterthanyou]

9-bolts and 12" are both power robbers so keep that in mind. If you plan on daily driving it and never putting slicks on the car then I would stick to the MUCH cheaper 10-bolt but if slicks and low 60' times are your goal in life then go for it now.

[NJSPEEDER]

enough people have built 10bolts up and run in the 11's with them that it is perfectly worth whiel to spend less than half teh price of a 12bolt.
28 spline axles as used in the later cars offer more contact surface and are stronger.
the 2 big things to 10bolt life are welding teh axle tubes and getting a good cover. 90% of teh failures that people have in 10bolts have everything to do with case deflection, not the strength of the gears or carrier.

later
tim

[IROCdan330]

does that whole metal tab thing work with 4th gen rears too? Â*mine is out of a 2001 t/a but i dont have the tag hanging off...yet i have one hanging off my 2.73 drum rear from my 87...and i know thats posi. Â*makes me wonder if ive got a 2001 t/a rear...did the t/as get the almost 12 inch rotors in the rear?

edit: oh yea, ive got a ws6 sway bar on it...or is it? its like 19 mm or so, smaller than my iroc one...but then again 4th gens got ****tier suspension stuff...hm.

[84HOtransam]

9-bolts and 12" are both power robbers .

9 inch and 12 bolt? how much do they rob...anyone have proof of this?

[Batman]

9-bolts and 12" are both power robbers .

9 inch and 12 bolt? how much do they rob...anyone have proof of this?

They will pull between 5 and 10 RWH from you, alot more rotating mass to push around, price you pay for strenght. If you can get away with a 10 bolt (not sure how much power you are making) it is the way to go. You can build a pretty beefy 10 bolt for about $1000, handle upwards of 400-425 RWH

[Batman]

does that whole metal tab thing work with 4th gen rears too? Â*mine is out of a 2001 t/a but i dont have the tag hanging off...yet i have one hanging off my 2.73 drum rear from my 87...and i know thats posi. Â*makes me wonder if ive got a 2001 t/a rear...did the t/as get the almost 12 inch rotors in the rear?

edit: Â*oh yea, ive got a ws6 sway bar on it...or is it? Â*its like 19 mm or so, smaller than my iroc one...but then again 4th gens got ****tier suspension stuff...hm.

I have a tag on my 2002, but like I said before, take the one bolt out that holds it in and it can get lost easily

[Tru2Chevy]

I would spend half the amount of a Moser 12 and get an Auburn Pro or Eaton posi carrier for the 10 bolt, and invest in some good 28 spline axles. Have the axle tubes welded, and get a girdle cover. That should hold you for a long time.

- Justin

[foff667]

I would spend half the amount of a Moser 12 and get an Auburn Pro or Eaton posi carrier for the 10 bolt, and invest in some good 28 spline axles. Have the axle tubes welded, and get a girdle cover. That should hold you for a long time.

- Justin

:stupid:

[84HOtransam]

9-bolts and 12" are both power robbers .

9 inch and 12 bolt? how much do they rob...anyone have proof of this?

They will pull between 5 and 10 RWH from you, alot more rotating mass to push around, price you pay for strenght. If you can get away with a 10 bolt (not sure how much power you are making) it is the way to go. You can build a pretty beefy 10 bolt for about $1000, handle upwards of 400-425 RWH

as the car sits right now a built 10 bolt would be more then fine...but it is a 5spd car and im planning on sticky tires and only more power... a 12 bolt may be over kill now...but id rather spend twice the money once then build a 10 bolt only to get the 12 bolt down the road..

[Tru2Chevy]

as the car sits right now a built 10 bolt would be more then fine...but it is a 5spd car and im planning on sticky tires and only more power... a 12 bolt may be over kill now...but id rather spend twice the money once then Â*build a 10 bolt only to get the 12 bolt down the road..

Do you really plan on keeping the 5 speed? Doubtful that it would withstand much abuse with sticky tires and a built 383....

I'm not gonna try to influence your decision, just want to make sure you have thought of everything.

- Justin

[84HOtransam]

as the car sits right now a built 10 bolt would be more then fine...but it is a 5spd car and im planning on sticky tires and only more power... a 12 bolt may be over kill now...but id rather spend twice the money once then Â*build a 10 bolt only to get the 12 bolt down the road..

Do you really plan on keeping the 5 speed? Â*Doubtful that it would withstand much abuse with sticky tires and a built 383....

I'm not gonna try to influence your decision, just want to make sure you have thought of everything.

- Justin

yes it will be manual..wont be the non-world class t-5 thats in there now..all three needed to be upgraded..engine, trans, rear...the rear broke first...

[Ian]

I forget which mag did the article, but it was a comparison between a 9 inch, 12 bolt and a dana 60. Whatever magazine that had the "supernova" project car. car craft! thats it. the 9 inch robbed the most power out of all three, then the 12 bolt, then the dana. The 12 bolt has C-clips and the other two don't. there really wasn't a down side to the dana 60, except it was a few pounds heavier. It was stronger too, cause the ring gear was the biggest out of all of them and the pinion contacted the ring gear in a better spot. If anyone is interested in the article, I'll try to find it.

[Batman]

The 12 bolt has C-clips and the other two don't.


Moser 12's don't have C-clips, must have been a stock GM 12 bolt