IROCZ28KevinZ

iTrader: (2)

hey all, i tried a search for my answers but came up with nothing. i just got a 9 bolt borg-warner posi/disc rear end and proportioning valve for $200 at a swap meet. the guy said that it has 3.23 gears; however, i wanna be sure. i checked on the gears themselves, but no markings; i found the tag on the cover, but it just says "spin resistant differential" on it and no codes. i have no other tags from it. i read in chilton's that the code should be on this tag, but it's not. any other ideas where to look? if i can't find the codes, how can i be sure it's 3.23?

also, is there ny way to test the calipers before putting them on the car? also, when i turn the u joint in the back (forgive me, i'm new to rear ends), both wheels turn in the same direction..is this good? i always thought one wheel turn opposite the other. there are no strange noises coming from the rear end; all appears to be in good health.

btw, in case it helps, it came off a 1989 formula 350 and has the PBR aluminum calipers.

thanks all!
kev

DJP87Z28

I am sure of one thing you did not get a 3:23 gears. 9-bolts gear ratios are 2:77, 3:27 and 3:45. You will have to remove the cover and check the ratio, stamped on the gear O.D. or count the the gear teeth.

You will need to clean the Calipers and replace the pads and check the hardware.

IROCZ28KevinZ

iTrader: (2)

hey thanks DJP87Z28..i went outside anc checked for those markings. i did find them; hey were kinda covered with grease and i didn't see them before. i didn't realize they were on the ring gear itself; i was looking on the ring outside it.

anyway, heres what i got: 0578-029009 BP 3 27 D

i take it that means i'm the happy owner of a 3.27 ration rear disc 9 bolt WB rear?

but, i still wonder about the tire rotation..is it normal for both wheels to spin in the same direction w/o any load applied to the rear? i always thought they spun opposite each other...

kev

TheGreatJ

A non-posi rear will spin in opposite directions if you turn it by the tire. If you turn it by the pinion, usually one tire will turn and the other will not.

Posi rears always turn the same way unless they're under a cornering load (or the posi is shot.)

IROCZ28KevinZ

iTrader: (2)

cool..so i guess this means that my posi isn't shot

kev

Verviticas

maybe, my posi (9 bolt) works like 60% of the time, burnout are always 2 lines, but hard turns i can feel both tires arent going.

acts the same way urs does when i spin it manually.

good news, if its acting like that then usually only needs spacers. look it up on the tech section. good info there i think its call "servicing 9 bolt rear end" or something to that end. later.

DoBeR

iTrader: (1)

I just upgraded from a 2.77 9 bolt to the same one you just got. It made a great difference and the PBR brakes are nice too, unless you have to buy calipers or brake pads.

The price for the rear pads was $115 canadian, we ended up getting a discount but they still cost more than a rotor.

kretos

good find on that 9 bolt

IROCZ28KevinZ

iTrader: (2)

I just got new pads for $18 US at Auto Zone. I also got new rebuilt calipers from O'Reilly's, at $65/side with all e-brake springs and levers. Lifetime warranty, too. I may need new rotors; I might just go ahead and buy them anyway because I have new pads and calipers, and with the rotors on the rear end now, they may not perform to their full potential. But we shall see.

BTW, the rotors just come off after you take off the calipers and the mounting bracket, right? Mine are stuck, so I hafta get em off somehow. Just wanted to be sure I wasn't missing anything.

DoBeR- next time you need pads, LMK what kind you want. If you pay me for the pads+shipping, I can almost guarantee you that it will cost WAY less than what you paid. True, I got the el cheapo pads, but I think even the better ones were cheaper than what you paid. email me when the time comes and I'll see if I can hook you up.

kev

Verviticas

geez, costs me lots more for pads. Napa AE's they were okay but pretty cheap looking compared to my bosch that i have up front. Personally im going ONLY bosch now untill i find better.

plus, i installed them (the bosch) with no squeeling or noises at all. they fit perfect. the AE's took forever to manage to get them to stop making noise..


Think my calipers are seized. need new ones (9 bolt). like 120 each here.....gotta find them cheaper... (vancouver canada), the fronts are like 40 bucks for both or something real cheap, haha.

and if i could get 18$ pads, i"de be going through them like crazy. even if they only last 4 months.

DoBeR

iTrader: (1)

My rear calipers cost me 99 each canadian, but we were able to get them for about 60 bucks each. The pads though I went with AC Delco. Never used them before but so far I like them.

When I bought my SUV the dealership put crappy brakes on it and they make all kinds of noise and theres nothing i can do about it besides change them all again.

As far as taking off the rotors, all you have to do is take off the calipers. The mounting brakes are behind the axle and you have to pull them to remove the bracket.

On both my 9 bolts the rotors didnt want to come off. The old one we had to use a torch and the other a hammer.

Lonestar

Are you having difficulty finding a rebuid kit?
Typically you can hone the bores and replace the seals much cheaper than buying new.

Verviticas

well my rear brakes really are weak, as in they sometimes dont even hold the car with the parking break and you can feel that the engage late if at all while driving.

the parts guy said they're probably seized and i need new ones.

please, tell me more about this rebuilding process.

do i just take them to a machine shop to be honed?

any part numbers for rebuild kits?

DoBeR

iTrader: (1)

The 9 bolt calipers are a little pricey but as far as im concerned its not worth rebuilding a caliper yourself for the price of a replacement one.

Basically they strip them down and clean up the piston bore and replace the seals.