ok so i just picked up a ford 9" yesterday. it needs axles and it needs brakes (as i assume our brakes will not bolt over to them), i do have disc brakes in rear i don't know if that makes a difference. im looking at something capable of handling 500hp and a little more of that in torque for my 383. i need some advice and or input. whats the best axles to put into it and what posi/upgrades should i do to it. i was thinking 4:11 gears since im using a t-56 6speed so i didnt think that would be to high really i already used 3:83 gears in my old one that i destroyed. it has the carrier and gears just not as beefed up as i think i need. someone just point me in the right direction. THANKS!!!

 

I'm a big Ford guy, so I'll try and put this as lightly as possible. The 9" was used for an extremely long time. A 1969 9" out of a Torino won't fit the 9" pig out of a 76 Torino. You have to find the proper carrier, proper POSI, proper axles, and proper gears for the year axle you currently have. Your best bet is to find what car it came out of and spread your search from there, I'd imagine the axle you have it out of a Granada, or a smaller Ford vehicle.

But it's not easy, We've got a 76 Torino, and we had purchased all new bearings, clutches and 3.25 Gears with a carrier in better shape than the one we had, to find it was all different, didn't even want to bolt up.

 

well then ill try pulling up some casting numbers and whatnot its on its way back from florida with my uncle to illinois. ill see what i can pull to inform you as much as possible

 

i bought my 9inch from moser and they installed end caps for me to use my stock brakes on i needed to machine the brake bracket but it works fine i used big ford ends i think they call them and the 4'11's will be fine i have 3'90's in mine

 

You picked up a 9" yesterday without axles or brakes? What kind of 9" is this? If it's not an aftermarket bolt in diff, what's it out of? You can't just put a junk yard 9" under a third gen with a lot of suspension changes. Chances are it's not the correct width either.

Ford uses 28 and 31 spline axles so without knowing the carrier spline count, you can't order axles. 31 spline is more than enough for most vehicles.

Ford also uses a handful of different bearing/backing plate styles so you can't even order an aftermarket brake system without knowing what style the ends are.

Unless this is a direct bolt in diff, you're wasting your money doing anything to it. It will be cheaper to just buy an aftermarket diff designed for a third gen.

 

edit:not even going to reply to that

 

It's up to you if you want to use it or not. You wanted advice or input and you got it. It's not our fault the answers you got were not what you wanted to hear.

Too many people think it's a simple swap to just change a non standard component without knowing what's involved in such a swap. If you have enough knowledge, chances are you won't be asking questions like those. Others go ahead with such a swap and realize they made the wrong choice or found out it's way over their head to do it properly and give up. Some try it on their own after doing much research and eventually get it done but normally at a higher cost than what a simple bolt in replacement would have cost.

You can ask whatever you want. Just don't get all pissy if you don't like what you hear.

 

Do you plan on using the stock suspension with the torque arm? As for the case, you can put any differential in any case as long as you don't go over 33 splines on the axles. All of the Ford cases will accept all of their differentials, you just have to use the right bearings. There are only 2 differential bearing sizes used by Ford in the 9 inch, the 2 7/8 and 3 1/16. There are 2 pinion housings used, the standard and the Daytona. I doubt that you have a Daytona unles you have a nodular case. There are 3 axle bearings and about 6 or more yokes, so you need to figure out what you have.

If the total width of the rear end will fit on the car then the only other thing that you have to look at is pinion offset. All Chevy car rear ends have the pinion offset 1/2 inch from center, which puts the pinion 1 inch closer to the right side than the left. If you are going to narrow this rear end to fit your car then you need to keep this in mind. You can get a set of housing ends from Moser that accepts the 9 inch axle bearings and GM brakes. Your discs might work with these ends and the right axles.

A set of 31 spline axles will be fine for what you have, but the differential selection depends on what you want to do with the car. Need more information on this one.

 

well compared to some people in this thread who think i have no clue what im doing instead of giving some advice, im going to be taking the differential out because it isnt a posi anyways, im going to buy a new detroit locker (limited slip) with a 31 spline as well as either 3:73 or 4:11 gears to compliment the t-56 that is going in there..i will decide after i upgrade the trans and look at what each gear in will bring to the table. i have a torque arm bracket that came with it from currie so i will be using a stock torque arm i wont need to go and adjust anything to use that. question comes up whats the rating on a stock torque arm?.ill also be replacing the bearings and basics just to keep it fresh im not going to half *** this project and will complete it the right way. i know it does not have anything fancy internally so it wont have that upgraded daytona peice. i know i will have to get the correct yoke and or u-joint anyone with clarification and or part numbers would be helpful.i will also be getting a bracket for the brakes so i can use my disc brakes. this should be the correct width too for a 3rd gen i think the guy took it into a shop and he had brackets and everything started for getting it into a 3rd gen he just never finished it. if i have overlooked anything let me know and any CONTRIBUTION in a non elitest way would help,yes i am learning still but i have a decent understanding on how to do this and a quick learner.
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also i forgot to mention if anyone has the correct part numbers from currie and or moser for the bearings and whatever odds n ends im forgeting would be greatly appreciated.im pretty much going to refresh everything and not leave older parts in it unless they are perfectly ok.THANKS!! john~

 

The Detroit Locker is a good choice for a street/strip car that wil see lot of strip time. It is stronger than the Traction Lock and more dependable when doing burnouts.

Just be sure to check the pinion offset. If this is not correct then the torque arm and drive shaft will not be in line with the car. This is important.

As for the yoke, most after market yokes are the truck type, which is shorter than the car yoke. You will probably need a longer drive shaft. The 1350 type is stronger, but the drive shaft needs to be made for this u joint.

I recommend getting an installation kit from DTS or Tom's Differentials to instal the gears. You need to know if you have a case for the 2 7/8 bearings or 3 1/16 bearings before you order a kit. You will also need to know which housing ends you have so you can get the right axle bearings and retainer plates.

 

ok ill check the last part out. thanks for the input greatly appreciated. i have to figure that out any way i can tell if he doesnt know what was in it? can i pull that from a casting number or from somewhere or do i just measure or what exactly am i looking for to tell,i know this originaly came from a torino i believe sorry if i mispelled that i dont know fords lol

 

Most of the standard cases had the 2 7/8 bearings, but not all. The only way to tell is by measuring the bearing bore in the case or the OD of the bearing race.

You also need to be sure of which pinion housing you have. Ford sometimes mixed up parts and installed standard pinion housings in nodular cases and Daytona pinion housings in standard cases. If both pinion bearings are the same size then you have a standard pinion housing. If the inner pinion bearing is larger than the outer then you have the Daytona. You will also need to know this before ordering a yoke. The Daytona uses a shorter yoke than the standard pinion housing.

 

ok thanks alot for all your help ill get into checking this and let ya know what i come up with