Gears & Axles - 10 Bolt Build VS 9 Inch VS 12 Bolt

Just as the title says..I've got a 6 speed Z28, basic bolt ons. Nothing too serious. I feel like I'm hearing some gear whine and some sort of roaring from the rear end. I decided I might as well put some money into my rear end before I go ahead and do anything else before the car won't even move. I'm not trying to drop a ton of money into the car but I'd like to do it good. Anyone have any opinions on what to do first? Or should I not even bother building my stock 10 bolt and go for a Ford 9 inch or a Strange 12 Bolt?

tons of threads on this, everyone says dont waste your time and money on a 10bolt. just keep saving for the 9inch best way to go!!

My ten bolt had been grenaded a few times by the previous owner and when I bought the car it was whining. Had it rebuilt with oem gears and it was quiet for a week until it started doing it again. I wouldn't waste your money on it especially with a 6spd.

Well now some people have told me to get a 12 Bolt instead of the 9 inch as it is more suitable for a 6 speed and the 9 inch is better for an automatic. Whats your guy's take on this?

Well now some people have told me to get a 12 Bolt instead of the 9 inch as it is more suitable for a 6 speed and the 9 inch is better for an automatic. Whats your guy's take on this?

That's backwards. Generally speaking, the 9 inch is stronger and better equipped to handle a hard launch with a 6-speed. The 12-bolt is a substantial improvement over the 10 bolt, however it has it's flaws. Given that the cost of the 12-bolt and 9 inch rears are so close, you might as well go with the stronger of the 2 (the 9").

Simply put -- don't spend $1,000 to rebuild a 10 bolt rear. You've repaired the broken parts, but it doesn't fix the real problem (which is the fact that the rear ends are too weak to support the power these cars produce). Put that $1,000 in savings until you have another $2,500 - $3,500 to go with it for the 9" build. It's a huge capital outlay however most would attest that it's the single best mod you can do for these cars.

I'm still on the crappy 10 bolt and you can't imagine how badly I would like to be able to dump the clutch at 5K and watch it roll out. Instead, I'm launching at 2,500, slipping the clutch and praying it makes it through the 1-2 and 2-3 shifts!

Well now some people have told me to get a 12 Bolt instead of the 9 inch as it is more suitable for a 6 speed and the 9 inch is better for an automatic. Whats your guy's take on this?

i would say it the other way around......12 bolt auto 9" m6 car.

9" is stronger than a 12 bolt in these cars because of the t-arm.

i have had a ton of 10 bolts & rebuilt a few of them....

i had a 12 bolt in my 01 m6 & changed it out for a 9" & its the best decision i have made for this car.

every time i went to the track with the 12 bolt it got louder & louder......

good luck!

Alright sounds good. I was leaning more towards the 9 inch anyways because I thought it was stronger too. Do you guys have any recommendations on somewhere that I could buy one? Also what would be all behind the installation of something like this?

S60 ;)

S60 (1 ton) axle - Not breaking that mother ....... - heavier than 9 but just as strong and cost less.

I had an S60 in my HCI LT1. I loved it and its pretty much one of the strongest rears out there. Alot of people like the 9 inch because it is easy to change out gears compared to a 12 bolt/10 bolt etc. 9inch or S60, you really cant go wrong and you dont have to buy the rear brand new. The parts classified usually has a few listed for sale.

I have a strange 12 bolt just cause I wanted to keep everything GM, but if I had to do it again, I'd do a S60, which is overkill for most people. The S60 weights a little more but has less parasitic loss.

s60 for heavy stuff, 9" then 12 bolt....... i will be throwing a good amount of power at the 12 bolt and yes it is loud, but with a giant cam and nitrous i could care less. :)

Interesting. So what else would I have to be looking to get to install one of these rear ends? I mean would they bolt right in ?

I have the MWC 9 inch and it bolted right in place like a 10 bolt would, I can't speak for the moser though. You'll need a different length drive line with any 9 inch and I wouldn't recommend a 12 bolt. I've heard to many horror stories about gear whine.

Another vote for the S60. It runs completely quiet as long as your follow the manufacturers instructions and bolts right in with no modifications. I got mine directly from Strange and they even gave me new bushings for the sway bar.

I have a 9 inch. Got the housing from QP and the third member from a Nascar team I work for. 9 inch with driveshaft cost me $1800. Just look for some deals and youll find them. I definitely wouldn't put a 12 bolt in it though. good luck, Start saving its worth it!

With the s60 or 9 do you have to get a whole new drive shaft or can you have stock one shaved down....if you have to get whole new one how much does that cost

With the s60 or 9 do you have to get a whole new drive shaft or can you have stock one shaved down....if you have to get whole new one how much does that cost

yes you need a new ds. they are different lengths. 10 bolt and 12 bolts use the same length ds. 9 inch and s60 are different. it depends on if you want a steel, chromoly, aluminum or carbon fiber ds. most start at $350 and go way up lol. I like the PST driveshafts, have a few buddys that run them seem pretty strong

Has anyone here tried building your own 9"? Like buying one from a salvage yard, re-use all the mounting brackets off the 10 bolt, etc.

If so, any links? What truck is the S60 out of?