Mach 1 Club

Full Version: 9inch rear end question.
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My 1972 "Q" code Mach 1, according to the door data, has a 3.25 rear gear. I have staggered rear shocks, factory front and rear sway bars, but I believe an open rear end. I would like to install a Trac-Lok limited slip...would I have a 28 spline' or 31 spline.

CJ pony parts has this one fron Ford Racing: 9'' 28 SP TRAC-LOK LIMITED SLIP DIFFERENTIAL 4-SPRING AGGRESSIVE TQ BIAS: 396.00 dollars...is this a good one?
Hey; I'm not 100% sure if theres a way to tell if it's got 28 or 31 spline axles with out pulling one. The rearend tag might tell if it's still there and god only knows if it's correct. As for the traction lock you listed it should be great for 300 to 400 hp general street use. It would display guick lockup under load as the word agressive hints at. You might have to be a little careful accelerating hard through a corner as it could suddenly lock and induce a slide. (which I would find quite enjoyable) But could catch you by suprise. Wet pavement would be the worst. It's something you would have to play with and learn it's characteristics.
Jts 71 Mach1
(10-13-2010, 12:15 PM)JTS71 Mach1 Wrote: [ -> ]Hey; I'm not 100% sure if theres a way to tell if it's got 28 or 31 spline axles with out pulling one. The rearend tag might tell if it's still there and god only knows if it's correct. As for the traction lock you listed it should be great for 300 to 400 hp general street use. It would display guick lockup under load as the word agressive hints at. You might have to be a little careful accelerating hard through a corner as it could suddenly lock and induce a slide. (which I would find quite enjoyable) But could catch you by suprise. Wet pavement would be the worst. It's something you would have to play with and learn it's characteristics.
Jts 71 Mach1

Thank you for the info. Will be pulling an axle this weekend.
This site has great info including how to identify 28 vs 31 spline by looking at the brake end of the axels
http://www.kevinstang.com/Ninecase.htm
(10-20-2010, 12:49 PM)IL_Mach_1 Wrote: [ -> ]This site has great info including how to identify 28 vs 31 spline by looking at the brake end of the axels
http://www.kevinstang.com/Ninecase.htm

Goodpost