Hi guys,
Just a query bout how wide is the 9” diff in a 69 ?
And is there a diff in the Ford family that is approx 2” narrower …
Im thinking about how i can get bigger rubber under the rear , i have plenty of room inside but getting close outer.
I currently running 255/60-15 on 15x10 Magnums, but would like 275 or even 295, i think 295/50-15 will fit but i still would like to keep the look
of a ?/60-15
Any thoughts … 
Duplicate
If you can find a 57 - 58 Ford or Mercury 9" housing they have the same spring perch locations but about 1" narrower on each side. You will have to use the 57 - 58 axles and axle bearings and use the '57 - 58 Ford brakes because that is a “big bearing” rear.
I also believe that mid 70 Granada, Monarch and Lincoln Versaille with a 351W had 9" rear axles that were the same size as the old 57/58 Ford units. But are not much easier to find. Early Mustang K codes I think got 9 inch rears and also are 2 inches narrower. But those are made of unubtainum. I’m not sure of bearing issues.
What width is the early 65-66 mustangs and 67-8 cougars…?
What if i cut 2” ( inch each side ) of my diff, can i have 28 spline axles off the shelf…? 
67 - 70 Cougar and Mustang 8" and 9" axle housings are all the same.
Have never seen a '65 - 66 Mustang 9" housing for sale at any price but they are the same width as 57 - 58 Ford, about 1" narrower on each side than 67 - 70 Mustang / Cougar.
No way to cut down a differential sorry.
28 spline axles are the same for 8" Cougar / Mustang and 9" Cougar / Mustang.
the lincoln came with the disc brake 9" my 75 Monarch with a 351 had an integral rear in it, but long ago when my friends uncle closed his junk yard in Brooklyn we found a 9" rear with drum brakes that was tagged 76 Granada. its been in my 68 Mustang for years and the tires tuck in nicely 235/60/15 drag radials on centerlines.
Hello Pete,
If you are interested in new rear axle components for your 69 Vert… Moser Engineering could be a source for consideration.
https://www.moserengineering.com The Moser fabrication shop is located about 35 miles from our place.
So how many have been cutting down differentials? Here’s a picture of a differential - how would that work exactly?
I was refereing to cutting an inch off the outer ends of the axle tubes .
You are correct Royce. The differential does not get cut down, the axle housing does. Bluestuff just used the wrong terminology when he said differential.
Randy Goodling
CCOA #95
Currie Enterprises is one of the best known custom narrowed and strengthened 9 inch ford rear ends.
https://www.currieenterprises.com/
There are also many other companies. It would be about a push to purchase from them vice finding a narrow Ford rear end from the sixties. Currie will build you a custom width 9 inch housing and axel combination to your measurements. You really need to be careful on your wheel and tire selection and take many measurements. First figure out what wheel you want to run. No how to measure backspacing and ensure if the wheel choice will fit your wheel well with the tire of choice mounted on it. Currie may have produced some widths in the past that you can lever off from. Once your are confident that the wheel and tire can fit in the wheel well and not contact the leaf spring, I would order them and purchase them and have them mounted. Then you can really dial in the housing width.
None of this is very easy. It takes patience and lots of double checking of measurements. Once you have tires and wheels mounted they are yours and most companies will not take them back. We can go into backspacing and stuff, but most wheel companies have drawings and such to help. I have done this about 10 times in my career and each combination is different.
Crager sells custom offset wheels that can accommodate larger tires in your wheel well. I ordered custom backspace Cragers and fit a 26 tall 275/50R 15 tire on a 68 Mustang. No rubbing and it was a bit lowered. I can send you pics in e-mail to see the fit. robvalcampbell@comcast.net. Photobucket is not being very friendly these days.
Rob
Do you have to specify that the currie is going in a Cougar? They list the same rear end for both Mustang and Cougar.
I’ve got a '59 Ranchero differential under my '68. It’s 2" narrower than factory, but the spring perches are in the correct place. It’s a small bearing setup.
I believe the widths are the same.
Rob
I agree Currie is well known and they do a great job. However they also are frightfully expensive! I recommend checking Moser against Currie before buying. Moser does exactly the same thing in most cases for a lot less money. Quality at Moser is outstanding. It’s probably just the difference between the cost of doing business in California VS anywhere else.
If you live in LA then Currie might make sense for something you could pick up in person to avoid shipping cost.