I've been reading through the old posts and was just wondering, is a moser 12 bolt really that bad? If I can get a really good deal on one for a six speed car that won't be more than 450whp + some juice would it be worth it? I keep hearing about torque arm bolt issues but I'd imagine if I put red loctite and nylon nuts on the thing, it isn't going anywhere. Any ideas on reducing gear whine, perhaps a certain gear manufacture or a different backlash setting?

thanks,
pete

 

Put a 12 bolt into a early Chevelle, Nova, Camaro, etc and you can beat the crap out of it, and not hurt anything. Put one into one of our cars with a torque arm, make a couple 4000 to 5000 dragstrip launches, and I can just about guarantee you'll pick up gear noise. If it is a drag only car, you'll never know or care about the gear noise. Drive your car home from the track, and the noise will drive you nuts. I feel the torque arm stresses the 12 bolt housing, causing distortion. We have never seen this happen with the 9 inch housing.

Exotic Performance Plus strongly recommends the Moser nine inch. This rear is even tougher than the Moser 12 bolt, and the horsepower of the late model F Body cars keeps escalating every year, which requires a very strong rear. With the recent introduction of the 6.2L GM aluminum block and the excellent flowing 6.2 litre heads, the horsepower of these cars is going to just keep climbing at a very fast pace.The nine inch will handle the power, plus we prefer the way the torque arm is bolted to the nine inch in the same way the oem rear-end is attached. (This is the only good thing about the stock 10 bolt...) The Moser 12 bolt uses four short bolts to attach the torque arm, and they have a habit of loosening up, even when loc-tite is used. Why the nine inch is stronger than the 12 bolt. The 9-inch has an internal rear-pinion support that also supports the gear end of the pinion to limit gear deflection under high torque loads. This seems to be the major reason why the 9 inch doesn't start whining after high rpm clutch dumps, when the 12 bolt will pick up noise.The 9-inch locates its pinion gear lower on the ring gear to improve tooth contact, than the 12 bolt does.The 9-inch has a 0.125-inch larger ring-gear diameter and internal pinion support than the 12 bolt does. This is not much of a difference, but it is worth noting. Bob

 

If installed with the proper hardware. no issues with the bolts. And proper torque on fasteners. Its the installs that give them a bad rep. Click on my name and you will see what Im talking about. Byunspeed has a guy making what Im talking about. Im going to make more of my own again, mine are out of aluminum(6061). Ive been running a H/C setup with mine since 04-05 on my Moser and since I made these. No problems. BTW Ive run them in a Spohn and SLP TQ arm.

 

a moser 12 bolt is all the rear you need, I am the 3rd owner of a 7 year old moser 12 bolt that has only been mated to a six speed tranny. this rear has so many clutch dump passes on it its not even funny, and I am talking about 450rwhp with 10" slicks pulling 1.5 60' times, and the sad thing is that its as quit now as it was new.

 

whats the price difference between the 9 in and a 12 bolt?

 

$0.00

That should make the choice easier

 

i like how you included the .00 haha

 

Wait it out for a 9"

 

Isn't it claimed the 9" will use up more power then the 12 bolt?

 

Possibly?

I swapped to a Moser 9" and added a rollbar.. but removed a few things (abs, spare tire, etc to help even it out.)

I lost about 0.1, but that may be from dropping down to a 3.50 from a 3.73.

 

Yes it is..

 

Figured I'd chime in since I'm an owner of a 1-yr old 12 bolt. I HATE IT!!!!!!! I had ear ringing noise the day it was put in. One year later, I can't stand it anymore and the installer has been working with me diligently to fix the problem, but I fear the only recourse is to replace the whole damn thing. My car's nothing special. Mostly stock daily driver.

The installer and I both called Moser after installation and they have just given us the run around so far. We're still working on it and I hope will come to a reasonable resolution.

 

Figured I'd update my post. Lonestar Performance, Garland Texas is Great. They worked hard to make my troubles go away. My 12-bolt still has noise but NOTHING like it did when Moser shipped it to me. Long story short, Moser was absolutely NO HELP AT ALL! I will NEVER purchase anything from them again and I would say the same to anyone who is looking. I'm picking up my car tomorrow and if I remember, I'll take a picture of the gears that came out of the 12-bolt and add it to the post.