Ok this is for all the diff gurus, of which I am not.
I have a diff which was sold to me as a 9 inch diff. I have checked all the dimensions and identified that it is a Big Ford “Old style” it has 28 spline axles which are 30.1 inches or 767mm long.
I want to convert to disc brakes, but my axle backspace is 2 inches or 52.25mm. I cannot for the life of me find disc brakes anywhere that suit a 2 inch backspace they are all 2.36 or 2.5 inch. Is a 2 inch backspace factory or is it likely it has been altered.
It’s doing my head in
Does anyone have any suggestions?
Lloyd.
9 Inch Diff…….Help!
- zuffen
- Old Hand
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- Location: Sydney
Re: 9 Inch Diff…….Help!
Photos would help us see what your describing or even a sketch a with some dimensions.
The slight backspace difference may only mean the calliper mount has to in a slightly different spot but you would most likely making them anyway so easy to sort.
Keep us posted and we'll do our best to help.
The slight backspace difference may only mean the calliper mount has to in a slightly different spot but you would most likely making them anyway so easy to sort.
Keep us posted and we'll do our best to help.
Never argue with an idiot, they will drag you down to their level and beat you with experience.
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- Senior Member
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Re: 9 Inch Diff…….Help!
This may help -
https://www.strangeengineering.net/wp-c ... r-Form.pdf
I expect you are talking about Dimension F which Strange call Axle Offset (Brake Gap)
Shows common Ford 2.145 - 2.3326- 2.500 - 2.625 and GM (USA) 2.8325
Photo would help and Good Luck - I am doing similar today
https://www.strangeengineering.net/wp-c ... r-Form.pdf
I expect you are talking about Dimension F which Strange call Axle Offset (Brake Gap)
Shows common Ford 2.145 - 2.3326- 2.500 - 2.625 and GM (USA) 2.8325
Photo would help and Good Luck - I am doing similar today
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- Posts: 6
- Joined: Tue Jul 14, 2015 11:26 am
Re: 9 Inch Diff…….Help!
This is the offset I'm referring to.
You do not have the required permissions to view the files attached to this post.
- zuffen
- Old Hand
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- Joined: Fri Jan 28, 2011 7:45 pm
- Location: Sydney
Re: 9 Inch Diff…….Help!
In your first photo what is the piece of steel you're measuring off? It doesn't look like it's part of the axle or calliper mount.
Could the diff be out of a Cadillac? They had odd brakes and bearings, if my memory serves me right.
To solve the spacing just make the calliper mount fit the dimensions you need.
That's real Hot Rodding!
Could the diff be out of a Cadillac? They had odd brakes and bearings, if my memory serves me right.
To solve the spacing just make the calliper mount fit the dimensions you need.
That's real Hot Rodding!
Never argue with an idiot, they will drag you down to their level and beat you with experience.
-
- Posts: 6
- Joined: Tue Jul 14, 2015 11:26 am
Re: 9 Inch Diff…….Help!
Thanks Zuffen,
The measuring picture is just a pair of vice grips holding a steel ruler to give me something to measure from.
It’s my first build and I’m just trying to keep things within my abilities
The measuring picture is just a pair of vice grips holding a steel ruler to give me something to measure from.
It’s my first build and I’m just trying to keep things within my abilities
- Sudsy
- Senior Member
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- Joined: Sat Apr 08, 2006 2:59 pm
- Location: Lower Mid North South Australia
Re: 9 Inch Diff…….Help!
Just get one of the discs you mentioned and mount the caliper to suit. If you get a solid disc use Skyline calipers with the handbrake integrated. They are the same as the fraud ones but easier to mount
Regards Bob
- FRANK BASILE
- Old Hand
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- Joined: Wed May 07, 2003 3:14 pm
Re: 9 Inch Diff…….Help!
To help this, go to the DBA website. And get the disc catalogue . They have a download. You can look up by make as it is in alphabetical order, they list the rotor specs Diam/thickness/hole center/ and offsets from hub to rotor inner face. Ford had variances in the latter. Other vehicles with the same bolt pattern can also be researched. Such as Mitsubishi Magna having Ford. Many years back. Harcourt motor wreckers in Vic. Had a caliper bracket available to weld to 8" diff axle tubes inboard of the flange. These used Nissan Skyline Pintara calipers. And Commodore rear rotors you had to re drill. So with some research using another critical measurement. Thickness to match what the caliper donor vehicle had with it's rotor. And the axle center hole diam. You can select a rotor with similar spec and make your own brackets out of MDF for a pattern and get some steel laser cut, I have done this mock up on a 62 Buick Special diff. They used 13" rims and have 4.5" x4 [114.3x4] bolt pattern. My wood pattern takes Nissan Pulsar calipers and the Pulsar rotor is used. Job is currently shelved covered in dust until I can get to dealing with other shit on this orphan vehicle.
OZ-E-Rodders Rod and Kustom Club Member #31