whats the best way to easily tell the diffrence between a 8'' or a 9'' rear axle? is there some marking or bolt pattern somewhere that will be pretty obvious? i know you can always check the door tag(what exactly that # woud be IDK) but if you just have a rear laying on the ground whats the most obvious sign to look for? thanks
If you can remove the bottom bolts with a socket (the ones around the outside that holds it to the housing),then its a 8 inch.
Reach under the passenger side of the axle and twist the tag off and read it. It should say 9 if it is 9 inch. The 9 inch also has an odd shape jutting out of the back of it. Look for pictures on google. An 8 inch is round while a 9 inch is more oval.
not all 9 inch rears have the odd shape...as the 57- 59 housing is smooth If the axle tubes have a taper, then it is an 8 inch I believe 9 inch axle tubes are not steeped down as the 8 inch is. look on the web for kevinstangs page. One of the best 9 inch pages out there. tyupe in kevinstang.
basically if you can get a socket on the bottom 2 nuts it's an 8". a 9" you need to get those 2 off with an open end or box wrench.
I just happen to have my 9 inch center section jammed in a bucket right now. You can see in the picture that there is a large section of housing, just behind the yoke, that hides those 2 bottom holes. That is why you need a wrench to get the nuts off.
Here is a picture to compare. You will see how the pinion on the 9" hangs lower than the 8. which is why you cannot use a socket on the bottom 2 nuts. Also notice how the 8" is flatter across the top and bottom.
madman, there isn,t much of anything in junkyards around here anymore.... they're just scrappin everything..not like the old days... I got a 9 inch in a yard down near cape cod in 1987....had an n case 430 gear 31 spline axles the whole bit...musta been from an scj mustang....and the punchline... it cost 20 bucks ..i couldn,t carry it out of there fast enough!! even worse ...I gave it away to a friend... what an idiot!
There's a surprising number still out there, and not all are still under their original cars. I pulled one from a 66 Stang parts car. It ALWAYS pays to look. Bad thing about the 57-59 9" is it looks almost exactly like a later 60's to 70's 8", what with the WAR case center (looks like the Nodular but without the "N") and smooth rear housing. When it comes to that, you lean back on the socket test.
I bought four 57 Fords out of a junk yard up in Maine last year. They was on ebay. Sold all four which more than paid for the auction and the cost of the trip to go get them. Got tons of good parts too.
Nice find! there are a ton in the junkyards here, just no posi. I got my 3.50 31 spline sitting in my garage waiting on $$ to shorten it.
