When will my 10 bolt break?

**Insert** · 06-05-2008, 08:32 AM

Originally Posted by DOHC Cobra

I was told that Ford rear ends would fit, is that true?

Eagle
12 bolt axles generally OEM'd from truck applications. 9" axles are Ford housings, which also came in trucks mostly and some older model heavier vehicles.

hope that answers.

**Hot Black Trans-Am** · 06-06-2008, 10:14 PM

Originally Posted by DOHC Cobra

I was told that Ford rear ends would fit, is that true?

If you put the brackets on and get customs axles with the GM bolt pattern you can. It's not just a pull out and bolt in operation unless you get one designed for a f-body from Moser or Strange.

**ksulkosky** · 07-01-2008, 10:10 AM

yeah, dana 60 is the way to go if your looking for strength

**rush007** · 12-15-2008, 06:20 PM

does having a lower gear help any? i have a 32000-3500k stall and looking on building the rear...thinking of going with a something under 3.73 gears since i plan on tt setup. also, where would i get a 12 bolt? is it a modded rearend from another year car, does it have to be shortened? still learning about this stuff and really want to do it right.

**epmedia** · 12-16-2008, 11:10 AM

Originally Posted by rush007

does having a lower gear help any? i have a 32000-3500k stall and looking on building the rear...thinking of going with a something under 3.73 gears since i plan on tt setup. also, where would i get a 12 bolt? is it a modded rearend from another year car, does it have to be shortened? still learning about this stuff and really want to do it right.

Lower gears will help the strength of the drivetrain from the rear pinion shaft, all the way to the engine crankshaft. A 12 bolt 4.11 was common for drag racing years ago, and may still be ? If I remember correctly; the 3.73 was common stock gears for day-to-day driving (saves fuel, etc..). As far as where to get a 12 bolt 4.11, and how to make it fit your car, I am unsure. Good luck and be careful under there!

PS: I bet there are harder bushings avail for the rearend pivots/joints/suspension as well (instead of the stock rubber)?

**rush007** · 12-17-2008, 07:24 PM

thanks for the response...another question, what year rearends from ford are the same length? i can get an 8.8 very easily and know of a burnt 10 bolt for parts to mod an 8.8. what needs to be done to the axels to get them to fit, does anyone happen to know? i know a fabricator but want to know for my own knowledge.

**crazy dave ls1** · 02-14-2009, 01:37 PM

Originally Posted by trprcar

Im upgrading to 3:73 in my 10-bolt will the reluctor gear from the 3:42 work or can I get one for an S-10 ?? if so then which year S-10 any input you have will be greatly apprieciated Ive been reasearching this for a month no answers-Bill

http://dagostinoracing.com/index.php...products_id=32

**ctkws6** · 03-03-2009, 12:28 PM

....mine just went out this week...it sux! How much is a 12 bolt? I want one eventually, i tend to have a heavy right foot

**2001ws6** · 03-13-2009, 06:03 PM

The comparison of 12 Bolt vs 9 Inch
http://www.chevyhiperformance.com/te...son/index.html

**6.0LiterImportEater** · 05-13-2009, 01:07 PM

Can you beef up your 10 bolt with the 8.5" ring gear? Is that even a possibility?

I mean a 8.5" 10 bolt is available compared to our puny one.

**Cutlass** · 05-13-2009, 06:58 PM

The 8.5 inch ring and pinion gear set won't fit in the 7.5" housing if thats what your asking?

**therym** · 08-24-2009, 07:02 PM

My rear end is sounding like I am being pursued by a DEA helicopter! Anyone know of a merchant selling complete 12" or 9" for less than $2k?

**animal323** · 10-24-2009, 10:17 AM

How do I beef up my 10 bolt?

You don't.

It seems like too easy of an answer, but it holds true. The 10 bolt will always be limited by the fact that it is simply smaller than a 12 bolt, 9 inch, or Dana 60. Smaller = weaker.

Besides replacing the ring & pinion and bearings, adding aftermarket parts such as stronger axles only seems to be a waste of money. The minute you fix one thing, another will break. Rear end installs can be costly if you are not doing the labor yourself - it adds up quick. Don't be the guy who says he can't afford a 12 bolt, but has spent $1500 dumping money into his 10 bolt.

I'm very new to cars and very curious to learn anything and everything i can and i no nothing about the differential and axles so i was wondering a few things. When they say 12 bolt and 10 bolt i no its the bolts on the diff but when they say 9" that would be the length of the tube from the rotor to the diff rite? In the tube would be the axle? With a 12 and a ford 9" would the wheels have to be changed to wider or skinnier tires? Or would the axle determine that? Whats inside the diffrential (gears, limited slip)? When people say they have a built rear what does that mean?

**cuzimoto** · 10-24-2009, 01:56 PM

My wifes 82 Bird has a rebuilt 10 bolt with 4.10s. Tiny pinion gear. First engine ran 86 passes down the 1/4 at Palmdale 12.9-13.2. We replaced that engine last year and have made 58 passes 7.4-7.6 1/8 mile, about 11.6 1/4. I'll let you know how many passes it takes to break it. It will break. Gonna put c clip eliminators in it for safety.

**Cutlass** · 10-25-2009, 07:17 AM

Originally Posted by animal323

I'm very new to cars and very curious to learn anything and everything i can and i no nothing about the differential and axles so i was wondering a few things. When they say 12 bolt and 10 bolt i no its the bolts on the diff but when they say 9" that would be the length of the tube from the rotor to the diff rite? In the tube would be the axle? With a 12 and a ford 9" would the wheels have to be changed to wider or skinnier tires? Or would the axle determine that? Whats inside the diffrential (gears, limited slip)? When people say they have a built rear what does that mean?

9" ford means the diameter of the ring gear is 9 inches. Our 10 bolt rear has a 7.5 inch ring gear diameter. Bigger gears are stronger.
If you buy a prefabbed aftermarket 12 bolt or 9", you won't need different wheels. They are built to put the wheels in the exact same place as the stock rear end.
The term 'built' usually means stronger or better whether someone is talking about rearends, transmissions, or engines.

**animal323** · 10-26-2009, 04:13 PM

Thanks for the response cutlass appreciate it.

**D.statt** · 10-28-2009, 10:27 PM

Im thinking of swapping my factory 12-bolt with a new aftermarket one. Mainly to pic up a little strength and to be able to reuse my 33 spline axles and spool from the current setup. Current housing has been welded on a few times and now Im moving springs and will need to do even more welding. Figured swapping may be best route. This seems to be a little less money that going with a 9. Ive looked at Currie, Strange, Moser, etc and a couple advertise to be the strongest. Any thoughts on which is better?

Does anyone know if the caps in the Moser are steel or cast?

Thanks,
John

**crossbredfoxbody** · 01-10-2010, 06:04 PM

With out a big stall or a trans break or a t56 the stock rear will hold up with a few modifications.

**Head Hunter** · 08-05-2010, 07:59 AM

Not one who likes to make assumptions, but is it safe to say that a torque converter is typically going to help break a rear faster?

**bberretta** · 08-06-2010, 02:54 PM

Can't speak for an Automatic, but let me put it this way:

November 2009- rebuilt rear completely with Richmond 3.73, bearings, aluminum rear end cover with bearing cap girdle, arp bearing cap studs, etc. Broke in right, made very little noise.

December 2009 - replaced with ls7 clutch.

May 2010 - Headers and Y (only real power adder on car)

July 2010 - New tires (put 315's on rear)

July 2010 - less than two weeks and only 300 milesafter tires, rear end goes out. Two teeth on ring, three teeth on pinion, and crack/hole in posi.

So how long 'till it goes out- there's no telling. Add a better clutch and tires that will hook up on a M6 and give it a couple of good, hard shifts and that's it- at least that was it for me! Now I'm just waiting for my WMC Fab9" to get here!