Ok guys, I decided to start this topic due to the fact that I KNOW I'm not the only one with questions about rear ends that we can install in our cars. I have a 67. I'm looking at a rear end to install. If we can strike up a chat about the 8.8's and 9's, gearing, splines, THE LENGTH and where it's measured from. Stuff like that so I along with others can be more knowledgeable on this area of our cars. I would like to get something that would pretty much bolt right in. Thanks in advance to you guys with knowledge in this area and sharing it.

 

Lets get Tyler in here to straighten out the 8.8 stuff. I kind of have been wondering about this stuff.

 

Exactly, I want knowledge before I do something to my car, and I figured there is no better site.

Knowledge or Bust

 

Can I at least get this answered? Is a 9inch out of a 69 Mach one going to bolt up and is it worth 350 dollars? PLEASE let me know before I make a 350 dollar mistake!!

 

I'm getting a few 9" LS rearends in the next week or so hopefully. For what I'm paying for them (75.00 for the first 2 and then that for each extra we take) I'm not being picky about what they come out of. Instead I'm going to have 2 lathe cut and weldingto the correct length and perches repositioned. A few places around here do it and I figure thats the best route for me. Keeping 2 for myself and have already sold 3 others for 200.00 each. We're thinking we'll be grabbing a few others as well to sell later.

 

A 69 9" is has the same demisions as a 67. That is a 54.25" housing, 59.25" axle face to axle face, and a spring perch span of 43". Im not too sure on this, but since its a Mach, it probably has a locker center and perhaps 31spline axles. Unsure of that though, but 350$ doesn't sound bad to me...

 

Thanks baddog, I appreciate the info. I had no clue what the measurements were and that helps. I'm not sure about the locker or spline either, if it's a 28 is that bad? Or not much difference? And I was thinking 350 for an axle that bolts right up wasn't too bad either. Just wondering on if it's as strong as others, although I'm not looking to put an ungodly amount of power to it, maybe 400hp tops someday.

 

28spline is stock for most of the mustangs. Even stock 8"s people will agree they can take a beating.

To put it in perspective, a 31spline axle diameter is 1.500" while a 28spline is 1.325" (I believe so on the 28, not 100% sure).

Do you have photos of the differentials, or know if its in good shape or not? There is a quick way to tell if its 28spline or 31spline, but you need to see the axle face, the place where the wheel bolts up. On the protrusion, if it's shaped like a rectangle inside a circle, its 28. If it looks like 2 small circles inside a circle, it's 31. Best I can explain it..

Or just look at the tag...