I have an opportunity to get a 9" rear end out of a '74 F100 for $100 drum to drum. It's equipped with 3.00 to 1 gears which will be perfect for my 223/T98. I'm thinking it should fit but I thought I'd come here and ask those who know. Any problems with this?

 

I'm thinking 3.00 gears seem pretty tall for a 223. If you live in really flat country it might be ok, but where I live is very much th other way (steep hills)and I have owned many 6 cyl trucks here for over 30 years. Here a 3.73 is too high geared and I have usually opted for 4.11s given a choice. I do normally run 255 85 16 or 9.50 33 15s, both of which are 33" tall and than can change things quickly. Soooo.... 3.00 wouldn't work at all for me. Flat roads, 26" low profile tires, maybe. Someone else might have experience with the 3.00

 

Thanks for the info. I calculated 2050 rpm will get me just shy of 60 mph using 29.5" tires. With peak torque coming in @ 100 rpm on a 223, I'm not sure which way to go. I have 3.50's now and I don't want to spend the $$ for a T5 trans. I do live in somewhat flat country but I do travel to areas that get down right hilly.

 

the 74 rearend i believe is 3" wider (1.5" per side) then the 59 rearend. i don't think the spring pads are in the same place either, so you would have to cut off the old pads and re-weld them in the correct location to fit in the 59.

the center section (pumpkin) will interchange between the 2 if they are the same spline count on the axles. the 59 should have 28 spline axles and the 74 could have either 28 or 31 spline axles.

rear ends up to and including 72 are direct bolt in with the 57 - 60 fords. same width and pad location.

rgds
Mike

 

1973: FoMoCo increased the rear frame rail width behind the cab from 33 1/2" to 37 1/2" on all...except the following: 1973/77 F250 4WD's (Highboys) and 1973/79 F350's on the 140" wheelbase.

1957/67 F100 9's use the same 28 spline axleshafts / 1968/72: The are two different 9" rear axles! One type has 28 spline axleshafts, the other has a 9 3/8" ring gear and 31 spline axleshafts.

9 vs 9/3/8: Only FIVE parts are the same: Housing gasket, pinion seal, one pinion bearing and cup, pilot bearing retainer. EVERYTHING else is different!
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1973/79 F100, 1975/79 F150: Could be 28 spline, could be 31 spline. There are two ways to find out.

Pull the axle, or if the AXLE tag is still present (many are missing today), have someone with the parts catalog decode it. But, there's more to it than this.

Once the code is matched to the axleshaft part number in the rear axle parts lists, this axleshaft part number then has to be looked up in the separate axleshaft ID charts to find the spline count.

How many people have the parts catalog? How many people that do want to go thru this PITA rigamarol? I know of one, there may be others.

1948/52 F1's, 1953/67 F100's have 11" x 1 3/4" rear brakes / 1968/79 F100's, some 1980/83 F100's, 1975/96 F150's have 11" x 2 1/4' rear brakes.

CAVEAT EMPTOR ~ Let the buyer beware: 1959/67, some 1968 F100's. If Limited Slip was ordered, Ford installed Dana rear axles / After the 1st Arab Oil Embargo ended, FoMoCo installed Dana 44 rear axles in some 1976/79 F100/150's.

Dana's have an inspection cover, the 9 inch does not.

 

ND, thanks. That's what I needed to know.