Seanphelps321

iTrader: (1)

I've been looking for a 9" or 12 bolt. I found an ad on Craigslist for one that seems pretty good but sounded expensive. Some of the things he talked about I didn't really understand besides the gear ratio and spline count. Just wondering if you guys think this is a good offer because I don't really know what to expect in full unit pricing of these things. Here's the ad...

I spoke with the guy and he told me $1800 now. I was already wanting 4.11 posi and it's disc brakes too. Does this sound like a good deal?

Another piece of info from emailing " its a 3rd gen stock length rear you can fit 5.5 backspace with 10 inch wheels 275 60 with small spacers yes its the small chevy pattern for the studs "

Atilla the Fun

Price is good, but that aluminum center would become cause for concern if you combine it with a T56 or TKO, and drag slicks.

big gear head

Probably a fair price. The aluminum Strange case is about $350 by it's self. The housing and axle package is about $1000. The differential probably cost about $350 and the gears would be around $220. Disc brakes are about $500 to $650. The installation kit is another $125, then add labor for assembly. If the housing is a after market bolt in housing then it's worth it, but if it's a junkyard housing that was built with used stuff then I'd be cautious.

Bullydawg

iTrader: (7)

I am currently building a 9" and I have figured that it is probably going to cost around 2300+ to build (used gears and trac-loc), and that is with free labor. I purchased a moser housing. I agree with Big Gear Head, if it is a junkyard housing then I would pass on it. If it is a known company name, I would try to bargain and get it a bit cheaper. I think it is a good deal though especially with the suspension stuff. I dropped $400 on the Adj Torque arm and still have to get LCAs, and on top of that I still need to get a driveshaft.

Overall, it sounds like a steal! Just find out who made the housing and see if he can take you for a ride if it is still in the car to check for noises and such. Ask him what type of diff is in there too...

Seanphelps321

iTrader: (1)

Well it's not in the car but he has pictures up. It looks real clean; inside and out. He says Strange Engineering center section and Moser axles. He also says low mileage but I would confirm that before proceeding.

Some pics...













Not trying to overload you guys with the pictures. I'm just not as experienced with this stuff and don't want to be ripped off.

I'm guessing he'll charge more for the torque arm.

I'm planning on a 385 with around 400hp/tq. Give or take a few. And a T56. I probably won't be putting slicks on it anytime soon. But I guess I should never say never. How concerned would I need to be? Should hold up a lot better than a beefed 7.5" from our cars?

sofakingdom

iTrader: (1)

Not sure what difference "T-56" makes in any of this, considering that, EVERY SINGLE ONE of the 4th gen F bodies that came with that, also came with a 10-bolt.

That aside, a 9" is a very inefficient piece of machinery; probably 15 - 25 HP extra drive train loss compared to a 12-bolt, and closer to 30 compared to a 10-bolt. Plus it weighs ALOT more. WAY WAY WAY overkill for a 385 unless there's ALOT of nitrous or a blower involved.

Yes it will "hold up better" than a 10-bolt, if there's abuse involved. Apart from that, it's bearings and gears and all such as that, with roughly the same longevity as any other rear, all things equal. Which it sounds like they are...

Pretty much eliminates most of the "abuse", right there.

OTOH, the ONE AND ONLY vehicle I have ever witnessed BURNING TO THE GROUND due to a fire started by its rear end, was about a late 60s Frod truck, with, .... you guessed it, ..... a 9".

The price is about right. Go check on the cost of one of those new, and then decide if it's a fair price.

big gear head

I'd like to see another picture of that differential. It look like a standard differential from this angle. Also the torque arm bracket looks kind of home made. Does he have all of the brake parts for it? I'm not sure about it. I'd need to see more pictures.

articwhiteZ

iTrader: (56)

all this Hub Bub about power loss with a 9"....stay on the porch..
the streets are unsafe for ya!

back in the 93 is when I did the upgrade after spitting out the stock units
with a 383... cost back then for bolt in unit with locker was $2300
all the testing that nascar has done shows less then 8 HP Loss
hell they even put the alt belt on the 3rd member pinion..but what do they know. they just drive left all day with this rear end..

anything over 350 HP and good tires and a day at the track and its your ring and pinon that let go in a 7.5 10 bolt.
no mater what upgrades you do to it...!

sofakingdom

iTrader: (1)

Hey, all he's got, is a small block. EVERY horsepucker counts. Has to. Now if he had some REAL POWER, .... it'd be a different matter.

UnstableAviator

That's identical to my late 90's Moser 9". Be advised if you bolt in another center section you'll have to grind it for clearance from the tq arm bracket.

30hp loss with a 9"? Ok, I'll bite. Yes, a 4.30 geared 9" will dyno significantly less than a 3.42 10 bolt. And of course a 4.10 10 bolt will dyno significantly less than a 3.42 10 bolt. There's been a few dyno enthusiasts on 'tech who have done nothing more than a 10 bolt gear change and shown ~17-20 hp LOSS.

But nobody races a dyno, and all the power in the world you can't use just makes you a Supra.

Good luck with your build.

Seanphelps321

iTrader: (1)

Overall, would a 12 bolt with 4.11s have less power loss and possibly be easier to bolt in with the tq arm? I think I'll let this deal go since I've read some things that concerned me.

big gear head

A 12 bolt will have less power loss, and it will be lighter. I don't know about it being easier to bolt in. There are several companies that make them. I know that Moser and Strange make them, and I think Mark Williams and DTS also have them.

Seanphelps321

iTrader: (1)

Ok. Maybe I'll just wait and see if one pops up somewhere. I know I can buy new aftermarket ones for my car but that gets really expensive. Hopefully a used one will pop up.

I know there's a way to take used ones from other styles cars and re-weld the brackets and all if I can get a hold of a good welder. What year car would I need to look for a 12 bolt from to do something like that?

big gear head

Installing a Chevelle, Camaro or other 12 bolt in a 3rd gen is a major job. There is a lot of fabrication involved to get the torque arm to work. You can't just weld mounts to it because the center is cast iron. You are much better off getting one that is made to work with the torque arm.

Seanphelps321

iTrader: (1)

That's what I was afraid of. Looks like my best bet for all of this is either a beefed up 10 bolt or aftermarket 12 bolt. I don't really want to gamble my money on whether or not a 10 bolt will hold or not though.

Any opinions on best brand to get the 12 bolt from? Would it be more cost effective to buy the housing from them and then piece it together and have a shop build it?

big gear head

I was a Moser dealer for 15 years and their stuff is pretty good. It's a lot stronger than the Chevy 12 bolt. They give you a $100 discount if you order it assembled from them, but you have to pay truck freight. If you order it in pieces you can have it shipped by UPS. I would at least get a housing and axle package if you wanted to get the rest of it from someone else.

I have no experience with the Moser 12 bolt for th e3rd or 4th gen. Some people have said that they had some problems with the torque arm mount. You might want to look into that before making a purchase.

Bullydawg

iTrader: (7)

If you are going 12 bolt with a T56, you have to worry about the torque arm mount tweaking the 12 bolt case and causing the gears to start whining. That is why I went with a 9". I don't see anything wrong with the one above. Here is my cost breakdown of the stuff I just got:
Moser 9" with axles -1,225.00 Shipped
Yukon AL 3rd member with install kit/pinion support/1350 yoke -565.00 Shipped
Strange 3.89 gears -179.00 Shipped
Durasolid forged Trac-loc -299.00 Shipped
Total -2,268.00

All the gear install and such is free, I'm having a friend do it. On top of this, I still have to get a driveshaft. Then the adj torque arm x-member mounted was $405 shipped... I'm going to be cutting it around $3k, but all my stuff will be new of course.

tom86iroc

iTrader: (1)

that torque arm bracket came from moser like that since I have one under my car now . I would see if you could get him down in price alittle NOBODY pays what people ask for lol I was just on Moser's site it would cost me 3 grand now to build that rearend except I'm using the nodular center section

tom86iroc

iTrader: (1)

http://www.strangeengineering.net/index.html the case is stronger then a stock 9 inch but weaker then a nodular one and he could always change the housing if he got a good deal on it just take all this into account if you buy it