The Stovebolt Site Forums The Shop Area The HiPo Shop Determining a 9'' from an 8.8 rearend??

How do you determine a 9' from an 8.8? I am looking at a 1970 Mustang rear axle assy. and owner says its a 9".I just want to be positive that it is a 9" Thanks for any input.

The 9" has a removable carrier and a non removable rear cover. it looks very similar to the '55-'64 Chevy Passenger car differential as well as the Chrysler 8.75 diff.
The 8.8 has a removable cover, integrated carrier, and looks similar to the 7.625 GM 10 bolt, only larger.

My suggestion would be to look some where else.

...... :mad:
The Forum for general pre-'73 GM truck-related issues and questions.
Use a GM rear end, they are cheap and plentiful.

BUT here yago................................................
http://www.coloradok5.com/axleguide.shtml
http://www.yearone.com/yodnn/tech/T...xleIdentification/tabid/455/Default.aspx
http://www.woodyg.com/fairlane/finfo/fordrears.html
http://www.4wheelnoffroad.com/axle.html
http://www.mustangsandmore.com/ubb/FordRearDimensions.html
http://www.kevinstang.com/Ninecase.htm
http://www.ridgenet.net/~biesiade/Fordrears.html


BUT
I GOTTA SAY FOR THE LIFE OF ME, THE INTERNET HAS /IS A POWERFUL TOOL ............................. USE IT
WHEN FOLKS ASK QUESTIONS LIKE THIS ABOUT NON SPECIFIC
TO CHEVY's/ OLD TRUCKS IT IS SO STU+&%$#LY SIMPLE TO GOOGLE AN ANSWER
ASKIN' US FOR AN ANSWER YOU PROBABLY COULD FIND QUICKER THAN IT TOOK ME TO GET THIS ONE POSTED



















FORD 8.8-INCH
The 8.8-inch debuted in 1983 Broncos and F-150s, and is now found also in 4.0-liter Rangers and Explorers/Navajos. It is easily distinguished from a 9-inch by having a cover on the back.


































FORD 9-INCH
The venerable Ford 9-inch is both readily available and strong. Later models have bigger axle tubes and stronger housings. It was standard under 1966-88 F-150s and Broncos. It also came on many vans and the Lincoln Versailles (a popular axle for swapping because of the Lincoln version's disc brakes with parking brake).








Ford Rear Dimensions
by Dave_C and the Fordnatics mailing list.
Here is a list of rear ends that I picked up some time ago on the Fordnatics mailing list.
These measurements are from flange to flange. Subtract 5" for bare housing length.

65-66 Mustang 57.25 inches
67-70 Mustang 59.25 inches
71-73 Mustang 61.25 inches

75 Mustang II 8" 57.00 inches
67-73 Mustang, Torino, Ranchero, Fairlane 9" 59.25 inches to 61.25 inches

67-71 Comet, Cougar, Mustang, Fairlane, 59.25 inches
71-73 Mustang, 61.25 inches


Where to find the 9" rear axle
67-73 medium and big block Mustangs and Cougars

I agree it is ez to search for the answer to this one. While it is true the dorf rear ends are not gm, they are sort of a standard when it comes to hotrodding. It is valuable information to know how to ID a 9 inch.

All that being said, I don't know why anyone would want to buy a used one and rebuild it when it is so cheap to get a new one made. The 9 inch rear can be made in any length with almost any lug pattern, any size and style brakes, any gear ratio and any type of traction enhancement. Not to mention you can have one built specifically to match the HP of your engine. It seems to me it would be a lot eazier to have one made to your specs than to hope to get lucky with a used one.

In a 1970 Mustang your choice would have been between an 8-in and a 9-inch. The 8.8 inch wasn't offered until later.