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1961 - 1966 F-100 & Larger F-Series Trucks Discuss the Slick Sixties Ford Truck

Another rear-end question

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Old May 13, 2011 | 08:33 AM
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Another rear-end question

I don't like to tag-on to other topics unless the question is along the spirit of the one asked by the O.P. so.....

I wanted to do the rear disc upgrade and I was hoping to get the kit ordered with my other parts from BOTP but i'm not ready to tear down the truck yet.

Being a '66 with a 9" rear end........was there a standard bearing size for that year?

I understand the whole small and large bearing and was curious if the small bearing hub ended up in the F100. I thought that to be for cars and the large was for the trucks but I may be mistaken. The easiest thing would be to just do the measurment but that involves breaking down one wheel and like I just said.....I'm not ready to get that far into things since I need the truck until the middle of July for some yard stuff.

I'm sure this question has been asked and answered prior but I couldn't find the post covering it.

Thanks for the help.

Joe
 
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Old May 13, 2011 | 01:24 PM
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If it is a 9 inch, it's the large ball bearing: D8AZ-1225-C (replaced: C9AZ-1225-A & C1SZ-1225-A).

Considering the age of the truck, it could have any one of the following. All are the same, cuz Ford just updated the part number a coupla times.

1961/68: C1SZ-1225-A - BIN: 88128 // 1969/77: C9AZ-1225-A - BIN: 88128-FPP or F-208-AKK or F-208-USA // 1978/86: D8AZ-1225-C - BIN: F-208-HL

BIN: Bearing Industry Number, marked on the bearing and are what autoparts stores, bearing shops go by.

This large ball bearing was also used in misc: Thunderbirds, Station Wagons, HiPo's and Police Cruisers.
 
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Old May 13, 2011 | 03:12 PM
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"If it is a 9 inch"

Now you have me second guessing myself.

Would there be another type that looks like a 9" and if so....what?

I'm 99.999% sure it's not an 8 cuz of the "pumpkin" on the rear of the case and it's not as "squat" in the diameter plus I've seen plenty of Dana's in my day that I'm sure it isn't that.
 
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Old May 13, 2011 | 07:48 PM
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There is only 1 "9" rear-end, but they did have a few difference between the years. The big bearing vs small bearing is on the outside of the axle tubes. Right next to your backing plates. Plus also around 1970 they switched to 31 spline vs your 66 28 spline.

You can measure the on center distances of the top 2 bearings, and that will tell you which one you have.
 
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Old May 13, 2011 | 08:30 PM
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There were two different 9" rear axles offered in 1968/72 F100's.

C8TZ-4234-A .. 28 Spline Axleshaft. This rear axle uses the large ball bearing.

C8TZ-4234-B .. 31 Spline Axleshaft-Use with H/D 9" w/a 9 3/8" ring gear. This rear axle uses a different axle bearing and seal. In fact, only 5 parts are the same as a 9:

Housing gasket, pinion seal, pilot bearing retainer, one pinion bearing and cup. Everything else is different.

1973/79 F100/150 9 inch: Some axles are 28 spline, some are 31 spline as it depends on the applications. Some 1974/79's have an axle bearing/seal combination (D4AZ-1225-A), again, it depends on the applications.

And, some 1977/79 F100/150's came with Dana 44 rear axles. Ford installed these after the first Arab Oil Embargo (1973/74) ended in an effort to improve MPG. Two ratios were available: 2.75-1, 3.00-1.

The reason I said "if it is" a 9" rear axle: Ford also offered 3 other rear axles for 1966 F100's: Dana 44 w/Limited Slip / Dana 60.2 w/Limited Slip / Dana 60.3 w/Limited Slip.
 
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Old May 13, 2011 | 08:59 PM
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Thanks for the claification Bill. Just couldn't figure how I could make a mistake on that one.

The next question I guess would be on the kit. BOTP offers a conversion kit that is for the 5x5-1/2 but they have it listed for the '48-'52 trucks. That should still work on the '66 wouldn't it?

9 inch Rear Disc Brake Conversion Kit - 5.5
 
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Old May 14, 2011 | 06:58 AM
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1948/52 F1's came with the Dana 41 rear axle / 1953/56 F100's came with the Dana 44 rear axle. 9" introduced in 1957.

A popular swap for these trucks is the 9" used in 1957/72 F100's.
 
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Old May 14, 2011 | 08:46 AM
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So that would be a yes. Thanks. at least I can now get that resolved too. For those of you out there doing a disc conversion, I found a universal proportioning valve from SSBC on Jegs website that has a hole for the brake light switch on a 66.

Here's a link.

Stainless Steel Brakes A0730 Stainless Steel Brakes Proportioning Valve
 
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