Will a ford 9" 3rd member from an early model bronco(Small style 66-77) fit my 9" assembly in my 84 F-150, are they the same splines?
also it has 3.50(he sais) but didn't all fords come with 3.55's??
can someone please give me the years with the different spline counts??
28 or 31??

Thanks,
Joel Thomas

 

I can't help with anything but the gear ratios you're talking about. Ford did make 3.50 gears in the early trucks - such as the E.B. 3rd member you're wanting to swap in. My 78 Bronco has 3.50 gears in it now.

It was also my understanding that Ford stopped making the 9" in 83, not 84, as you state your truck as being. Could be wrong tho, wouldn't be the first time.

 

 

Joel wrote:

> Will a ford 9" 3rd member from an early
> model bronco(Small style 66-77) fit my
> 9" assembly in my 84 F-150, are they
> the same splines? also it has 3.50
> (he sais) but didn't all fords come
> with 3.55's??

Although all 9" rear as the same "design", there are several things to consider when trying to interchange parts or assemblies.

1) Are the yokes the same? If not, aftermarket u-joints are available to do a coversion.

2) Splines. Your '84 is most likely (never say always with a Ford) 31 spline. I would not be suprised to find that the early Bronco is 28 spline. If you can find a tag on each of the rear ends, the numbers can be decoded (Hollander Interchange is one source) to tell which axles, and ratios you have.

3) 3.50 is a 9" Ford gear, 3.55 is a 8" gear or a 8.8" gear. 3.56 is also a 9" gear, but not nearly as common as the 3.50. Seems most every 1/2 ton Ford 4X4 I have seen has been 3.50 or 4.11. But with Ford, I am sure there are others out there. 3.00 is one that comes to mind.

4) I have seen 9" axle in Ford trucks as late a 86. I did see one in an 87 van. Factory?? Not sure.

Hope this helps,
Mark