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RiggerWings
Joined: Wed Nov 15th, 2017
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JAMMAN wrote:
I thought FX4's and sport models had 31spline 8.8 standard? How can you identify a 31spline without breaking out the tools? Lol
My '11 Sport has the 8.8 and 31 spline, as did both of my '02 FX4s. My '08 Mustang GT has an 8.8 and I'm pretty confident that it's 31 spline. I'm not sure if there's a different length on the axles or axle housings though.
My Mustang rear end has several differences though, spring perches, an "eye" atop the diff for the upper control arm. Shock mounts should be the same, but spring perches would need to be removed to mount u-bolts and leafs. Maybe a newer or older Mustang read end would suffice though.
To answer your question though, measure your axle tubes. The larger tubes (3 1/4" which is 10.25" circumference) are the 31-spline axles. The smaller (2 3/4" which is 8 5/8" circumference) tubes are 28-spline. The last link below says the tubes are 3" (not 2 3/4") and 3 1/4" respectively, just measure and see where you end up. Good info in these links though.
http://www.therangerstation.com/Magazine/winter2017/how_to_spot_a_ford_ranger_fx4_31-spline_axle.shtml
http://www.therangerstation.com/stock-ranger-specifications/ford-ranger-rear-axles/
http://www.therangerstation.com/tech_library/Ford-8_8-axle.shtml
____________________
-John
2011 Ranger Sport 4x4, daily
2008 Mustang GT, garage queen
2013 Mazda CX5, grocery getter
2018 Harley Davidson Road Glide Special, the toy