9 inch rear end
Senior User
Joined: Apr 2009
Posts: 377
Likes: 2
From: Ashland, KY
i have those pics on my other laptop, its at work, i dont know why it uploaded it smaller than it was, unless FTE automatically resizes large files, i can email it to you monday if you need it.
Post Fiend
Joined: May 2008
Posts: 7,641
Likes: 21
From: Poway, Ca.
Good diagram from mostly52f1 but these old eyes have problems reading such small words. So pardon the stupid question but I have never taken a rear end apart, but where are the spider gears albuq f1? So Julie are you saying I should look for another third member and not rebuild the one I have?
There are a few things that I'm not entirely comfortable doing myself - ring and pinions and setting those correctly is one of them. And that's funny because most of the guys that think that's a snap shiver at rewiring.
At this point Pappy, I would probably take a step back and look around a bit - see what I can get as far as another vs rebuilding, and weight the options.
Hotshot
Joined: Oct 2004
Posts: 15,882
Likes: 88
From: Durham NC
Well, that's kind of a matter of opinion I guess. For me I can go out and find a good one that will last me 20 years and pay $175 for it ready to install. But for me to rebuilt - inside and out would take days plus the parts cost. That is kind of where I was coming from with that. If they are that hard to find where you are maybe the rebuild is better. But fact of the matter is you can't use what you have, as is, if you have chips.
There are a few things that I'm not entirely comfortable doing myself - ring and pinions and setting those correctly is one of them. And that's funny because most of the guys that think that's a snap shiver at rewiring.
At this point Pappy, I would probably take a step back and look around a bit - see what I can get as far as another vs rebuilding, and weight the options.
There are a few things that I'm not entirely comfortable doing myself - ring and pinions and setting those correctly is one of them. And that's funny because most of the guys that think that's a snap shiver at rewiring.
At this point Pappy, I would probably take a step back and look around a bit - see what I can get as far as another vs rebuilding, and weight the options.
Even then unless you are extremely lucky the R&P is likely to howl after having already been run in.
The spider gears are the 4 smaller gears at right angles to the ring gear inside the housing the ring gear bolts to. That assembly is what allows a differential to work.
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 790
From: Simi Valley, CA
NO 1969/72 F100 ever came with a Spicer (Dana) rear end.
If the F100 you got the rear axle from is still around, get the AXLE code off its Warranty Plate.
The most common ratio used in an F100 with an A/T from 1966 thru 1979 was 3.25-1 - AXLE code 17.
1957/72 F100's came with 9" rear ends, but...if Limited Slip was ordered, 1959/67 and some 1968 F100's came Spicer/Dana 44's.
Some 1961/68 F100's also came with the optional Spicer/Dana 60 with or without Limited Slip.
Some 1968/72 F100's with either 360 or 390 V8's have a ring gear that's 9 3/8" in diameter. Regardless, this is still classified as a 9 inch.
1973 and later: F100 (1975/ F150) rear frame rails are 37 1/2" apart, so the 9" axle housing is wider.
Prior to 1973, the rear frame rails are 33 1/2" apart.
--------------------------------------------------
Julie:
WDT-F, F1 = 1966/70 Ford LTD/Galaxie / Mercury Marquis/Parklane/Monterey: 9 3/8" Rear Axle / 2.80-1 / 31 Spline Axleshafts.
6GC: Assembled the third week (C) of July (G), 1966 (6).
I can decode any AXLE tag from any FoMoCo car or truck from 1948 thru 2002.
Post Fiend
Joined: May 2008
Posts: 7,641
Likes: 21
From: Poway, Ca.
--------------------------------------------------
Julie:
WDT-F, F1 = 1966/70 Ford LTD/Galaxie / Mercury Marquis/Parklane/Monterey: 9 3/8" Rear Axle / 2.80-1 / 31 Spline Axleshafts.
6GC: Assembled the third week (C) of July (G), 1966 (6).
I can decode any AXLE tag from any FoMoCo car or truck from 1948 thru 2002.
Julie:
WDT-F, F1 = 1966/70 Ford LTD/Galaxie / Mercury Marquis/Parklane/Monterey: 9 3/8" Rear Axle / 2.80-1 / 31 Spline Axleshafts.
6GC: Assembled the third week (C) of July (G), 1966 (6).
I can decode any AXLE tag from any FoMoCo car or truck from 1948 thru 2002.
I had bits and pieces of it but you filled in all the blanks!
I find it a little strange after listening to these discussions about transplanting rear ends out of trucks that this one would come out of a "Big" Ford or Merc. I believe the 9 3/8 also came in the "Camper Special" trucks. Most of the guys say "go find an XX year F-100 and it's a direct swap." But I've never heard anyone talk about direct swaps out of the cars!
Elder User
Joined: Sep 2007
Posts: 968
Likes: 0
From: webster wi
were are you in Missouri and are you in a hurry i can get you a 3rd member resonably and i guy i work with lives there but he may not be home for a few weeks
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Fleet Mechanic
Joined: Apr 2008
Posts: 1,373
Likes: 6
From: Moore (or less), OK.
I have a 289, c-4 automatic and my 9" is a 3.0:1 ratio. Not very quick but decent mileage.
If the unit you have turns, you could always mark one brake drum and turn the pinion by hand counting the rotations to determine roughly what ratio you have at present.
The spider gears allow one wheel to turn faster or slower than the other for making turns. The outside wheel always turns faster than the inside wheel because it travels farther in a larger radius arc through the turn.
If the unit you have turns, you could always mark one brake drum and turn the pinion by hand counting the rotations to determine roughly what ratio you have at present.
The spider gears allow one wheel to turn faster or slower than the other for making turns. The outside wheel always turns faster than the inside wheel because it travels farther in a larger radius arc through the turn.
Post Fiend
Joined: May 2008
Posts: 7,641
Likes: 21
From: Poway, Ca.
Here is a Gear/speed calculator that is excellent.
The size of your back wheels and tires makes a big difference. Plus, it depends on what kind of driving you want to do. If you want to do freeway and have 15 inch rear wheels, a 3.00:1 will have you at 2750 rpm at 65mph. I have a 2.80:1 and it's perfect for freeway driving 2400 RPM at 65 MPH.
Here's the link to the calculator:
Gear Ratio Calculator
The size of your back wheels and tires makes a big difference. Plus, it depends on what kind of driving you want to do. If you want to do freeway and have 15 inch rear wheels, a 3.00:1 will have you at 2750 rpm at 65mph. I have a 2.80:1 and it's perfect for freeway driving 2400 RPM at 65 MPH.
Here's the link to the calculator:
Gear Ratio Calculator
Hotshot
Joined: Oct 2004
Posts: 15,882
Likes: 88
From: Durham NC
I find it a lot handier to mark the pinion and the wheel, then turn the wheel 1 turn, counting the turns of the pinion. A little less than 3 turns =2.80:1, 3 1/2 turns = 3.50:1,
3 3/4 turns = 3.70:1, 4+ a little turns = 4.11:1, etc etc.
3 3/4 turns = 3.70:1, 4+ a little turns = 4.11:1, etc etc.
Hotshot
Joined: Nov 2000
Posts: 11,591
Likes: 14
From: Pflugerville, tx
If you turn the wheel 10 times, then it gets a lot easier to be clear.. hard to make a mistake with the differences..
almost 31 turns, 3.08 (30.8/10)
32.5 turns, 3.25
35.5 turns, 3.55
37.+ turns 3.73
41 turns 4.11
Sam
almost 31 turns, 3.08 (30.8/10)
32.5 turns, 3.25
35.5 turns, 3.55
37.+ turns 3.73
41 turns 4.11
Sam
Thread Starter
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Laughing Gas
Joined: Sep 2008
Posts: 966
Likes: 27
From: Missouri
Another question about mounting my 9 inch rear end. I was wanting to mount the shocks back to the stock location but I think it is going to be like finding the needle in a hay stack finding shock plates to fit the 3 inch diameter. At least in my area. Seems no one has any old parts anymore around here. I was wondering if the shock mounts on the 72 rear end came be used and just have to change how they mount on top?