i just picked up a 9 bolt tonight, ring gear #s are 029012 308 borg warner# does anybody know what gear ratio this may be. i havent had a chance to count teeth yet and brakes are froze up so i cant turn pinion yet untill i get them freed up. thanks in advance for any help. and if any body could help whats the best way to check condition of clutches in this diff without ripping it all apart, i took cover off it looks pretty clean inside.

 

From the #s that you gave you have a 3.08 BW. Thats a pretty good all around ratio. As for the posi, the BW uses friction cones and not clutches like an Eaton. If you have the cover off then you should be able to take a look too see how worn your cones are. there are two windows on each side of the carrier that you can just see a tiny portion of the cone peaking through. If the cone is actually bottomed out in the carrier you need to pull it apart and see if its rebuildable. I got lucky when i did mine and the cones had not gotten a chance to eat away at the carrier. If your carrier is chewed up then it would be best to get another.

Here is the link to the PDF that i used to rebuild mine. Hope it helps answer some questions
http://www.geocities.com/luckyducky_...air30Nov04.pdf

 

thanks for the help, posi cones are not bottomed out yet but close, iam gonna have to rip it apart i guess, looking at a set of 3.73 right now, i got a 3300 stall 3 speed.

 

They are going to be close. Mine are very close but not touching. As long as they are not touching you should still be good. Its not all that hard to open it up and check though while the rear is still out of the car. If you have any questions at all like where to get bearings and seals let me know. Ive been there and ran into a good amount of problems that i can help you avoid. Also if you find you need shims to shim it tight again...i have a package that should do the trick for you. I bought two packages thinking i would need both but only ended up using one to get it perfect. I wouldnt want too much for em..probably around what i paid ($15).

 

ive seen on other web sight where they machine small end of cone slightly and install more shims to get it tightened back up, is this a good idea? i will try to post a link if interested.www.geocities.com/luckyducky_96701/9-BoltPosiConeRepair30Nov04.pdf

 

Yup same link i posted a few posts up. Thats how i did my 9 bolt. Works great.

 

interested in extra shims that you may have

 

You will also need A 3 series carrier if your going from 3.08 to 3.73. your 2 series carrier wont work.

 

from what i understand i have a 3 series carrier, i may be wrong though, i thought only 2.77 gears were 2 series? http://www.9bolt.com/gearsets.html here is a page that made me believe so. if i have a 2 series carrier do they make a shim to go behind ring gear to make it possable to run a 3 series carrier?

 

3.08's are on a 3 series carrier.

 

PM me and we'll talk. Ill be home next weekend and i can give you the exact number of shims and sizes. All i know is that i played around with combinations and got my posi perfect with exactly one package.

 

Where did you buy the shims?

 

I ended up getting them from a local speed shop that had them collecting dust. They are pinion depth shims that are the right dimentions to do the job. Im not sure where else you can get them. Basically you have to use whatever you can find.

 

just took rearend apart today, my posi cones are not groved and sit about 1mm from case half on one side and better than that on other, better than that all bearings were still good. iam waiting on the set of 3.70 gears i ordered to install. i have looked around and cant find the bearing for the pinion seperate, i only need the one closest to pinion gear does anybody have a part# or link for one of these bearings?

 

http://ratech.stores.yahoo.net/79bogmax.html

 

head bearing is closest to pinion gear right? i hope so thats what i ordered along with a solid pinion spacer and shim pack, thanks for the link.