I need to know for sure how many splines our axles are, I'm bartering for a new centersection with a locker, but can't confirm my spline count- it's a '75 Lincoln 9" with disc brakes, 2.76 open carrier, and the bolts holding the center section in are 9/16" head. Can't locate an axle tag, and I don't want to have to tear it all down.... anybody have a magic bullet? thanks!
I think the problem is he doesn't know whether to buy a new 28 or 31 spline, because he hasn't pulled an axle out of his own car to confirm what spline his rearend is now.
I've been told that you look at the end of the axle in the drum register area. If it has a sunken oval shape it's 28 spline. If it has two recessed holes, it's 31 spline. I have not looked around enough to confirm this as 100% positive, but maybe it will help.
You may have also read this info here, this page is quoted quite often with pictures: http://www.kevinstang.com/Ninecase.htm There is a problem with this method though. I have a 68-72 halfton 9" with N center and 31 splines that have that pattern on the end of the axle. The problem is I picked up a '57 halfton 9" from a fellow HAMBer with this 31 spline pattern also. Pulled an axle to verify, and sure enough it has tapered axles with 28 splines. So I know the pattern isn't an absolute way to check, but might get more accurate as you get into the late model cars. It also might be that the other pattern is always 28 spline, I don't know enough to be sure.
I have seen them both as 28 and 31 so don,t go by that. I do believe if the axle flange nuts are bigger than 9/16 with large bearings it will be 31.
I think you might discover lots of rears with big bearings and flange bolts will have 28 spline axles. But you won't find many 31 spline rears with the small flange bolts. those lincoln rears I mentioned that were 28 spline had big fat axles that were turned down to the 28 spline size. just pull an axle and count, don't bother trying to guess, ups to ship the wrong parts back costs too much. Grouch0--you meant 9-3/8" maybe? 9-1/4" is a mopar rear...
When I was looking for a center section for my Willys, I brought one to my guy, who does a lot of NASCAR stuff, and he called it a 9 1/4 (mid 70's Lincoln I'm pretty sure). It had a little wave in one of the webbings above the pinion. In any case, it may be of no use, not being a true 9"
oh, that explains the 1/4 vs 3/8" confusion, not a big deal....the important thing is that there is a bigger Lincoln rear. But that seems to be a late 60s-early 70s thing, they switched to the normal 9" rear for lincolns by the mid 70s as far as I can tell.
Yeah, not certain on what years. I just remember something about not all 9 inches, being 9 inches. And that it had to do with a Lincoln. And that my guy called it a 9 1/4
the later ford van rear i have in my garage has big bearing small flange nuts 9/16head and 31 splines.No surefire way to tell without pulling it.
thanks guys- sorry i didn't get back to this sooner. Yup, I needed to know offhand cause I'm a) in a hurry b)lazy and c) it is like 30 degrees in the garage Anyway- it's a disc brake rear so i couldn't use the flange imprint method, and since it is disced I can't get to the bolts on the backside- and in fact, they look like rivets tackwelded on anyway. My Factory service manual only ever mentions that it is a 9"- does this mean there may be some variation, or would this rear be a real 9" if the service manual says that? thanks!
take off the caliper, take off the rotor, take out the axle....I think that's how it works? The funky 9-3/8" has a curved rib on the 3rd member, it's pretty easy to spot
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