Im looking into a Ford 9 inch that came out of a 68 bronco. it already has 4:88s,31 spline and a spool. It is it big bearing or small bearing? Any downfall to be small bearing? I would run it as is then in the future go to 35 spline and spool. I am planning on putting this under my CJ-7 that willl have it wheel base stretched slightly and SOA. I know the pinion is super low. Should I have any probems rotating the pinion up. I have a 60 that I was gonna build but it is gonna take longer and I dig the 9 inch for the weight and strength. I tried searching and found some good info but nothing specific. Thanks:beer: RobK

IMHO a 9-inch is just as strong as a stock 60, and can be built even stronger, without giving up the ground clearance of the 60.

There won't be any problems with rotating the pinion up that I'm aware of.

Speaking of 35-spline axles and spools... anyone have a good recomendation?

There is no way that a 9" is a strong as a 60. The gears in the 60 are larger, the shafts are larger, the housing is larger... seeing a pattern?

Housing being larger does not equate strength.
Also, sure.. the Dana 60 ring gear is taller, but it is also thinner, thus not providing as much strength. A 9 inch Pinion is larger.
Here is some facts:
http://performanceunlimited.com/illustrations/gears.html

a big bearing 9 inch out of a bronco depends on the GVWR of the vehicle. you can tell by measering the diameter of the the bearing, the small bearing is 2.834" diameter and the large, 3.150" diameter. you can tell without measuring the diamter by the retaining bolts. the big bearing bolts are 1/2", which means a 3/4" head. the small bearing are 3/8" bolt. the downfall of the small bearing is you cannot go to 35 spline, it is weaker and you cant get a tapered roller bearing for it. just some information for you.

dan

let me know if you have any more questions.

I haven't seen the axle yet but I belive it out of a Early Bronco. I was hoping to find out the scoop behind small bearing verse big bearing. That is my major concern because I would like to run 35 or 40 spline in the future. Will the 31 splines be enough for 37s,4:88, NP435 and a 4 to 1 in the tcase. The WMS to WMS is 58 inches which would be almost perfect for my full width 60 inch waggy up front. Thanks RK:smokin:

I'm running 35x15.50 sx's (Likely heavier then the 37's you'll be running), 4.88's, and a T-18, no 4:1 transfer case. I don't have a problem with breaking the 31-spline rear axles at all.

Dear Lord lets not start this again. Sure the numbers on the 60 are bigger and better but the 9" will take a TON of abuse.

I had a 9" in my YJ and now have a D70. To do it all over again i would run the 9" again, I would 35 spline it, shave the bottom and be done.

To answer your question about rotating the 9" up, I've run one in a CJ-7, SOA +2" for 2 years with it pointed directly at the transfer case with no problems.

Originally posted by Rob Kosinski
Im looking into a Ford 9 inch that came out of a 68 bronco.It is it big bearing or small bearing?


Go to this page from Wild horses 4x4 web page,

http://www.wildhorses4x4.com/18.asp

scroll down half way and you'll see the way to determine if it is Big bearing. 1/2 stud for the backing plate is NOT a gaurentee of big bearing.

Good luck.

Eric

Originally posted by sethmark
There is no way that a 9" is a strong as a 60. The gears in the 60 are larger, the shafts are larger, the housing is larger... seeing a pattern?

Yep I see it! Closed eyes and head buried in the sand.:flipoff2: :p