[kro10000]

Sorry, I'm kinda a newb when it comes to this stuff. I've got a 72 Fastback 351c 2v FMX with the factory 2.75 geared 28 spline 9 inch in the back. I'm wanting to swap the 3rd member for one with a lower gear and a limited slip. However, if there is one for 31 spline axleshafts should I be worried? Obviously I will need the 31 spline shafts, but are there any other parts needed to swap to the better shafts? Are the 31 spline shafts hard to come by in a factory vehicle, and what should I look for? I am on a pretty tight budget, so I am avoiding going with aftermarket axle shafts at this time as they arent really necessary with my relatively mild motor.

Thank you in advance

 

[Leon B]

The 31 spline will fit with no problem, but finding the correct length axles to fit could be interesting. You could get some axles made to fit, the cost isn't really that bad. Also when looking for axles, be aware that there is a large bearing and small bearing version of the 9" housing that requires different axle bearings and as a result I believe the axle size at that point is different for the two bearings.