IF 9" rear ends are such power-robbers. . .

[Nuke]

Why are they so popular? What is it about the 10-bolt that makes it break and the 12-bolt last? Aren't the gears manufactured by the same people? Can a 10-bolt be made indestructable?

[Transamman25]

10 bolts are weak mainly because of smaller ring gears ..although and 8.5 10 bolt is right up there with the 12 bolt as far as strength goes .. not all 10 bolts are weak .. the basic point is the larger the ring gear the more area stress can be distributed to thereby decreasing the likelyhood of a rear end meltdown.

[gettinthere]

To add on his response, the 9" is more popular especially in 6 speed cars because of it's durability. The are as close to bulletproof as you can find.

[LiquidFire350]

To ass on his response,
:eek: WHAT????

[Trevor86TA]

I am not sure if you were implying this, but 9" are not the same thing as 12-bolts. Both can be bought by aftermarket vendors with various options (ie. 31, 33, 35 spline axles) however while the 12-bolt is more efficient, the 9" is maybe more common and makes gear changes pretty fast.

[LiquidFire350]

I am not sure if you were implying this, but 9" are not the same thing as 12-bolts. Both can be bought by aftermarket vendors with various options (ie. 31, 33, 35 spline axles) however while the 12-bolt is more efficient, the 9" is maybe more common and makes gear changes pretty fast.
im pretty sure the 9" is more durable of the two, ive come to the conclusion that:
M6 = 9"
A4 = 12-bolt

[Jaberwaki]

http://ls1lt1.com/forum/showthread.php?t=892

see the rear end section

[gettinthere]

:eek: WHAT????


Typing quickly > me

[Blown 25thT/A]

http://ls1lt1.com/forum/showthread.php?t=892

see the rear end section


That is the best write up I have read yet.

[Hark_Z]

I have never even heard of a GM 8.5 10-bolt, how much are they? All I always here is the 12 bolt?

[Trevor86TA]

I have never even heard of a GM 8.5 10-bolt, how much are they? All I always here is the 12 bolt?

That is the stock rear end in a lot (most) GM cars including recently 2nd gens and G-bodies.

One of the big troubles though with swapping any factory rear end into a 3rd or 4th gen though is the torque arm mount.

[Vader]

Nothing like 11+ inches of ring gear to distribute the power:

http://marksmark.net/srpics/bad162.jpg

[snakeoilperformance]

I have never even heard of a GM 8.5 10-bolt, how much are they? All I always here is the 12 bolt?


and most B-bodies (impala ss, caprice, etc.) certain years . they can be built to hold alot of power.

[AJ52486]

My truck has a GM 8.5 inch 10 bolt. Too bad I don't have enough power to break a 7.5 inch.

[snakeoilperformance]

swap em

[Firehawk 526]

The only problem I have w/9" is the HP loss and ABS loss, but IMO and particular situation (M6), I would be willing to give up a few ponies for the added security.

The ABS is something I really want to retain, but we'll see come decision-making time. Heck, NOT like I will be putting out 600+ HP (lol), so a 12 bolt will probably be sufficient.

[CamTom12]

is that a Dana?

[CamTom12]

The only problem I have w/9" is the HP loss and ABS loss, but IMO and particular situation (M6), I would be willing to give up a few ponies for the added security.

The ABS is something I really want to retain, but we'll see come decision-making time. Heck, NOT like I will be putting out 600+ HP (lol), so a 12 bolt will probably be sufficient.

I kept my ABS with my 9"...

[Firehawk 526]

I kept my ABS with my 9"...


What kind if I may ask? Moser or Ford w/locker or spool?

EDIT: Never mind, just saw your sig (my bad)

[CamTom12]

Moser. I just ordered the exciter rings on my axles when I had to replace them. I'm still working out a good way to get the sensors in there permanently, but that's because I have an older housing with bigger axle tubes. The newer housings don't have any problems with them at all.

[Firehawk 526]

Driveline-Solutions said they could build me a 3 ch ABS system for a 9", but who knows what may be available in another year or two......NO hurry yet!

[CamTom12]

oh, you're 3-channel?

There's a couple of places that can do it, it's really not that hard.

Don't know if you'll see a whole lot of R&D going on in this area, though... Not to rush you, but the options are already pretty much out there. I'd take Driveline up on their offer, they're reportedly a pretty good company (I haven't had the priviledge to spend my money with them yet, lol)