12 bolt and 9 inch questions

**JaycenK** · 03-03-2010, 01:08 PM

I am at that point where I've built the trans now the engine and I need to start sizing up the 12 or 9inch rear. What costs are thier in swapping it? and what do they cost? where do you get them? say what can I get away with now and then add on later. I am a 97 with 383 and LE2 heads and cam, trans is good to 500hp I don't go to the track that much mostly street, ASR and ABS that I want to keep for the wife. I have stock LT1 rear brakes but would like to go LS1 or bigger to go with the LS1 front brakes. Talk to me What are my options? I am thinking of doing this in the next few months. What pars can I reuse and what needs or should be swapped or added to my order of a rear or to the car. thanks

**LSCyaL8R** · 03-03-2010, 01:50 PM

This thread is relevant to my interests.

I too am in the market for a Moser 9 inch but don't want to lose my ABS. I'm certainly going for reloc brackets and LCA's at the same time as the rear.... not so hot on the PHB because I want to go to a Watts link since it's my belief that they do a better job of maintaining center through all phases of driving.

So my questions are much the same.

I want a better rear... I want to keep my ABS and I have no clue how to go about getting all the right parts together to make it work right.

**pajeff02** · 03-03-2010, 03:30 PM

I bought a Moser 12 bolt in December for our car. Upgraded with a True Trac, 33 spline axles, welded sway bar brackets and relocation brackets, and set up for 4 channel ABS, it was $2,800. Pics of what it looks like and the install on our car: http://www.ls1.com/forums/showthread.php?t=127890

The only issue with the install was modification of the parking brake brackets to accomodate the relocation brackets. That is detailed in this thread: http://www.ls1.com/forums/showthread.php?t=129401 Other than that, it was a fairly straightforward swap. I did go with a PST driveshaft that is about 1/2" shorter than stock. There was not a lot of clearance off the back of the trans as the 12 bolt housing is larger.

**JaycenK** · 03-03-2010, 04:56 PM

I see that it had just the carrier in it? you had to put the axles and bearings in? I could do that too but I was hopeing for something you just fill with oil, mod you E brake brakets and bolt on your brakes and put it in. Is it possible to get them like that or is it really expensive that way?

**pajeff02** · 03-03-2010, 05:03 PM

Originally Posted by JaycenK

I see that it had just the carrier in it? you had to put the axles and bearings in? I could do that too but I was hopeing for something you just fill with oil, mod you E brake brakets and bolt on your brakes and put it in. Is it possible to get them like that or is it really expensive that way?

The axles come in the box along with the bearings, hardware and rear. They ship it that way as you have to press the reluctor rings off your old axles and on to the new axles for the ABS/TCS. After that, install the factory backing plates and then press on your bearing and lock ring. It's not that complicated to do.

**JaycenK** · 03-03-2010, 05:14 PM

how do you press on the bearings? do you need special tools? same question for the rings, what is needed to do that?

**pajeff02** · 03-03-2010, 05:16 PM

Just used a standard shop press. There are pictures in the thread I linked of the reluctor ring being removed/installed -- can't remember if I posted a pic of the bearings being installed.

**JaycenK** · 03-03-2010, 05:42 PM

I have a press so I think I can handle the rings. Did the rear come with instructions on how to do the bearings and the rings? I think if I am given instruction I can do it but, you know...I like to have someone with experiance do the important stuff lol. I understand how rears work and go together but have not done one myself yet. I guess as long as I don't have to set up pinion preload and shims and all that I should be ok. I just worry I'll Fubar something and cause a BIG BIG problem.

**pajeff02** · 03-03-2010, 06:07 PM

The instructions were not all that great. Here it is play by play as I did it:

1. I ran a rag soaked in denatured alcohol down the axles tubes to clean out any debris. A clean broom handle works great for pushing it in and out of each tube. I also used brake clean to wash off the pattern dye and flush any debris out of the housing.

2. I believe it is easiest to remove the stock axles while the rear is till in the car. Pull the wheels, remove your caliper and disconnect the brake line at the union. I immediately capped the open line with a vacuum cap to prevent fluid from leaking and to limit air infiltration. Remove your caliper bracket and brake rotor. Pull your axle cover and rotate the posi until you see the small bolt head on the side of the carrier. Remove the bolt and extract the c-clip spacer from between the ends of the axles. Disconnect and remove your ABS/TCS sensors before pressing the axles inward -- you can tap them with a deadblow hammer also -- and this should allow the c-clip to be removed off the end of the axle. I fished mine out with a magnet. Then simply pull your axle out and remove your backing plate.

3. Remove your parking brake as you will need some space to install the new t-bolts

4. Press your reluctor ring off the old axle and onto the new axle.

5. Slip your backing plate over your new axle as it needs to be in place before you press the bearing on.

6. Press the bearing on all the way to the axle shoulder.

7. Press the lock ring on tight to the bearing. I warmed mine up a bit with a propane torch as they do press hard.

8. Install your axle seal in the end of each tube.

9. Insert your axle and then bolt up your backing plate with the new hardware before re-installing your parking brake and ABS/TCS sensor.

10. Fill the axle and use limited slip additive, if necessary, then remove the old rear axle and install your new one. There is also a break in procedure that requires running the car in the air both in drive and reverse for a brief period, and then another break in on the road.

**JaycenK** · 03-04-2010, 05:47 PM

cool thanks for the instructions. Did you buy yours direct from moser? or somewhere else?

**pajeff02** · 03-04-2010, 06:11 PM

I believe KY Speed may be the best resource even if they do not list them on their site. Send Mark a PM.

**Cutlass** · 03-04-2010, 06:16 PM

Along with the rear end you might need all or some of these to get the rear sitting in there just right:
adjustable torque arm
adj lower control arms
adj panhard bar

Cost really starts to add up

**marksls1ta** · 03-04-2010, 06:28 PM

let me know if we can help.

Thanks for the mention guys.

Mark

**JaycenK** · 03-05-2010, 12:53 PM

Originally Posted by pajeff02

I ordered it through a speed shop up by Buffalo, NY -- they helped to make sure I got everything right. I could have ordered direct from Moser and I believe KY Speed may also be a resource even if they do not list them on their site. Send Mark a PM as I have found that their prices are sometimes better than ordering direct from the manufacturer.

yup I talked to Mark and he got me a price. thanks again Mark. And thanks cutlass for the heads up there, that is kind of what I thought. Thanks for kind info pajeff02, Now that brings up something else. Are those parts like the adj torque arm and adj control arms and adj panhard going to have to be specific to a 12 bolt or 9 inch? If I can go ahead and get them on the car now that would be cool, or are they going to have to collect dust until I can afford the rear?

**pajeff02** · 03-05-2010, 01:06 PM

Originally Posted by JaycenK

yup I talked to Mark and he got me a price. thanks again Mark. And thanks cutlass for the heads up there, that is kind of what I thought. Thanks for kind info pajeff02, Now that brings up something else. Are those parts like the adj torque arm and adj control arms and adj panhard going to have to be specific to a 12 bolt or 9 inch? If I can go ahead and get them on the car now that would be cool, or are they going to have to collect dust until I can afford the rear?

They are all the exact same pieces that you can use with your 10 bolt. Since our car is not lowered, I elected to go with non-adjustable LCA's and panhard bar.