mcbitchman

Ok so the wife broke the ring gear in her ten bolt posi. I'm looking to replace the whole assembly. What do you folks suggest? The current one is a 373 and a bit low for me. This is an 84 S/E that came w/ every option I can think of so I want to keep it as close to the RPO as possible. Also what parts should be replaced w/ this such as axle bearings etc. The Bird has the WS6 pkg , and oh my does that stuff work well.

big gear head

'84 should be the 7.5 10 bolt with 26 spline axles. Is this correct? Check the RPO codes and see what the original gear ratio was. I would guess it was probably a 3.42 or 3.23.

If you have the money to spend on it then contact Tom's Differentials and get a new Eaton Posi, US Gear and one of his installation kits with axle bearings and seals. Remove your axles before ordering anything and see if they are worn where the bearings run on them. If they are then get a set of Tom's 28 spline axles and 28 spline Eaton Posi.

If you need to save a little money then contact a guy on ebay by the name of monzaz and get a Yukon Dura Grip, Yukon or Nitro gear and one of his installation kits. The parts are not quite as good, but should work fine for a car that doesn't get used every day.

Assuming you have a 700R4 transmission I'd go with the 3.23 or 3.42 for a driver.

mcbitchman

Hello Big Gear,,, nice thread on the 10 bolt FAQ by the way.. no this car was ordered w/ the 373's and a five speed along w/ about everything else incl close ratio steering WS6 etc etc. I have taken out the axles just haven't cked out the spline count although I would think they are the original ones. Wife trashed out the clutch tearing out the center piece at the same time, already replace the clutch etc. didn't know the rear was trashed during the process although it had a whine from when I got it ( traded a pellet stove for it).. so I figured it was going. I go the clutch from Rock Auto, AC Delco unit. I've had good luck w/ Rock. I was thinking of the Trutrac but heard Eaton is cool also. I like the idea of going to 342 because it revs a bit high on freeway and first gear is almost useless. I've never set up a posi unit like this one so that's what I may need some help w/ as well as the parts needed to do it right. It has the disc rears and the driver side fluid line broke off when I took the caliper off damn.. Pretty neat car so I would like to keep it close to the RPO... hey I really appreciate the quick info.. I have painted it black w/ pink glitter fading from the front to back... (wifes car).. lol look forward to chatting w/ you again. dj

mcbitchman

ps whoever bought it new had a clue as to what they wanted it to do as far as mileage and performance etc. love the 15 inch rims and boy does it corner well. A little short on power but what the heck it's a 2.8 so... although I hear one can get over 500 out of them... oh my

big gear head

http://www.ringpinion.com/Calculators/Calc_RPM.aspx
Use this to try different ratios and see what you like best. Do you know what the 5th gear ratio is in your transmission?

mcbitchman

not really sure and I haven't cked out the RPO to see if it's in there. I've attaced a copy of the RPO sheet for your enjoyment..... that calc machine is very cool and I thank you for all the gathering of info and data sheets, very cool , makes it interesting to see what has been done and how it came from the factory as well as all the variations of builds some of which we probably don't even know of only the buyer knows.... lol so 342 should work well any things you might offer as advice ,, also the numbers marked on the ring and the housing are as follows: on the ring itself... what looks like BRA very faint,, then GM22521257 then a lean forward box with H 9 inside and then 11:41 good night talk at you tomorrow thx again. dj

big gear head

GT4 is the 3.73 gear and G80 is the LSD, most likely an Auburn.

mcbitchman

what is LSD stand for? and what is Auburn?

big gear head

Limited Slip Differential (posi). Auburn is a brand of LSD, probably the one you want to avoid the most, and the one that was most often installed in the 3rd gen Camaro and Firebird.

1991sleeper

iTrader: (-3)

All gear ratios are based on a 26" tall tire ... I have 4.10's and with a 28-28.5" tire it comes out to the same as running 3.73's with 26's