OK, I've read this forum up and down, decided to take a chance and swap a 9 bolt 3.27 in my car, and now it's giving me fits. On the off chance it is something silly that was skipped on installation I'll reserve judgment but so far I'm nervous about this swap.

In case this helps another reader down the road, I would recommend that if you are thinking about a swap and happen across a 9 bolt Borg Warner differential, reconsider purchasing it. Don't get me wrong, I think the 9 bolt was (is?) a great idea and the 3.27 ratio is certainly attractive for my drive train but the parts for these things are kinda hard to get according to the content on this forum. You would be better served with a 10 bolt off either a 3rd or 4th gen car.

http://www.9bolt.com

This is at least one resource I am aware of concerning this component. Any one else have any raves or razzes for this piece?

 

Great rear end for the 3rd gen and I would have kept mine if there was some kind of aftermarket.

 

What's it doing that's "giving you fits"? Bearings and seals are common auto parts store items. Gears and posi units are the less common items since they only came in 3rd gen F bodies, but there does seem to be an awful lot of them around. The 9 bolt is a better piece in so many ways that I'm willing to put up with a little less availability of parts. I picked up a spare one for $150.

 

I sold my 9Bolt and swapped to a 10bolt for the gear option I found.

 

i just did the swap myself, from 10bolt to the BW 9 and i must say, what a hell of a rear end!! i got everything with mine from disc to disc with the brake cables for 250 and its got 3.45 gears. there is a way to purchase parts actually ive read something about australia. i duuno but next time i go there (which will be soon) im going to find out some info maybe i can bring something back to the board for all us 9 bolt guys. i think its worth it, wouldnt pass it up..

 

That would be nice. The stories I've heard about folks stateside talking to BW distributors in Oz is that they are not interested in shipping to the US. Kinda cost prohibitive I suppose.

My axle is clunking under power from a stand still and when it shifts to second. On top of that there is a metal on metal sliding noise that increases in volume with speed. I find out the score later next week on it. Hoping for a backlash adjustment and lack of enough posi additive.

 

they are not as expensive as they were in the past
i just rebuilt an 89 unit with pbr brakes
ring and pinion=$165
bearing kit=around$170
new cones=$177
axlebearings and seals=$80
pbr brake rebuild kits=$11x2
hoses hard lines brake cables=around$50

my posi cones just started to touch the case so the case was in perfect shape
the cases are spendy
these rear ends are only expensive if you are in a hurry to rebuild
i shopped around for almost a year before i rebuilt mine

 

Where did you source those parts?

 

i got rid of my 9 bolt when i snapped the spider gears in the posi after a weak 1.79 60 foot on my bolt on L98

had 2.77 gears, bought a used 3.27 ring/pin and posi for 210 bucks i think it was and broke it after 5000 miles or so, with only a few race passes on slicks

went to a 10 bolt for 3.42 gears, and big 12 inch ls1 brakes... for 300 complete. i could not find a new posi for that 9 bolt for less than 250 so i swapped rears. 4th gen rear is better deal anyway with parts available everywhere and nicer brakes

wouldnt mind keeping the 9 bolt but there are no parts that i could find other than ring and pinions, and overpriced used posi's. I didnt trust another used posi for the high prices ppl on here charged. ridiculous. oh well

 

ring +pinion i believe were from randy's ring and pinion they are motive gear

bearing set is from randy's

cones are from 9 bolt.com

brake rebuild stuff from napa im an auto tech and gave the list to my napa rep to order = nobody had any of it on hand

 

9 bolt.com still in business?

 

The website is still up-

http://www.9bolt.com/

 

yup i bought my cones from them a 3 months ago
it took a month to get them though

 

Ah 9 bolts are such a junk rear I wouldn't even bother wasting money on the thing. If it's in your car now and your stock leave it but if you plan on making power down the road start saving your money for a new rear.

 

kinda vague
how much is "some" power to you?????
did you have a bad expierience with 1 ????
do tell!!!!!
slicks or street radials?????

ive got a buddy who races an 88 gta 500 tq and h.p. on slicks been racing this 9 bolt for 4 years now replaced plenty of trannies same original 130k mile 9 bolt rear end

 

just another person who thinks if it aint a 12 bolt or 9 inch it aint any good... 9 bolts are nice i love mine. sure there are better but u can use these for some fast street cars.....i wouldnt run full slicks on them but then agian i wouldnt ever think of running slicks on any street car at the track....

 

Na just another sucker who thought 9 bolts can hold up and spent a lot of money on it.

 

like i said, my 9 bolt broke with a stock L98 turning 1.7x 60 foots.... some hold some dont, just like 10 bolts

7.625 ring gear compared to a 7.75 inch.... that extra little bit doesnt really help 12 bolt or 9 inch FTW

 

JT Performance

I got all my 9 bolt stuff from them. Every rear is different so to say that all 9/10 bolts won't hold up etc is a vague statement. Guys run mid 10 sec cars on stock rears all the time with DR's.

 

Yeah with simple bolt-ons i was having problems, the end for me was when my rear was making lot of noises, probably pinion bearing or gears but when I took out my first axle was thrilled to see my splines were shifted about 3/8-1/2" lol.

Looked like this

.|||
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9 bolts are good rears you do need to know their limits though
ive seen them take alot of abuse
i picked a 9 bolt for my car for greater strength over the 10 bolt and the 89 pbr disc brakes (i had drums)
my car has a 527 horse and515 tq 406 sbc
and will always have a zr speed rated tire so it will live a cushy life
if i decide on drag radials im comfertablle with that with the strength of the 9 bolt (i would get better axles though)
12 bolt rears are not that great either
9inch and dana/s60 rears would be the best choice the s60 being a slight winner imo

 

For daily driving (my application with an LO3) it should be an ideal component... and as it turns out, I have broken transmission mounts. So mine could turn out fine for a spell.

Yeah... I'm a little embarassed now but the thought of rebuilding my unmatching-numbers differntial is a new concern. I still love the gear ratio and performance boost from the 2.73 unlimited slip.