building my own front diff. Ford 8.8 LSD

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asand

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Doing a little research I've found that the AAM 8.25 has 28 spline axles. Early Crown Vic, Ranger, and other ford 8.8 rear ends also had 28 spline axles. My plan is to narrow an 8.8, put 4.11:1 gears and a LSD in it, and stab some AWD AAM 8.25 axles into it. I've already picked up the AWD diff and started building a jig.20240910_160201.jpg20240910_155834.jpg
 
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rockola1971

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"AAM 8.25 has 26 spline axles. Early Crown Vic, Ranger, and other ford 8.8 rear ends also had 28 spline axles". I hope the 26 and the 28 somewhere in there is a typo. Also are GM and Ford splines dimensionally the same? The gaps between the splines and the width of the splines themselves? Ive never been a ford guy so zero experience in that dept.
 
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asand

asand

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"AAM 8.25 has 26 spline axles. Early Crown Vic, Ranger, and other ford 8.8 rear ends also had 28 spline axles". I hope the 26 and the 28 somewhere in there is a typo. Also are GM and Ford splines dimensionally the same? The gaps between the splines and the width of the splines themselves? Ive never been a ford guy so zero experience in that dept.
Sorry, that was a typo. They are both 28 spline. I'll fix OP. Looking around the net, with a very few exceptions Axles and diffs have all the same spline "pitch". I'll know as soon as I pick up an 8.8 rear end.
 
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Mudsport96

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Curious as to end game here. Just to have a LSD front diff? Not knocking the plan, Ya just didn't explain the plan well... and I'm dumb and don't seem to be able to figure it out. Lol. The 8.8 is a tuff unit though. Ran a turbo 500+ inch ford through an 8.8 in a fox body in the early 2000s. Granted it had Strange axles, but factory ring and pinion.
 

justirv

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Curious as to end game here. Just to have a LSD front diff? Not knocking the plan, Ya just didn't explain the plan well... and I'm dumb and don't seem to be able to figure it out. Lol. The 8.8 is a tuff unit though. Ran a turbo 500+ inch ford through an 8.8 in a fox body in the early 2000s. Granted it had Strange axles, but factory ring and pinion.
My guess is to replace the 8.25 front diff. It's a known weak component and not much (if anything?) in the way of aftermarket upgrades available. I recall seeing others try a 3/4 ton (2500) swap, which I beleive turned out to be extremely difficult. I'm very interested in the OP's results.
 

rockola1971

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My guess is to replace the 8.25 front diff. It's a known weak component and not much (if anything?) in the way of aftermarket upgrades available. I recall seeing others try a 3/4 ton (2500) swap, which I beleive turned out to be extremely difficult. I'm very interested in the OP's results.
I believe Eaton still makes aftermarket units even though Eaton still makes alot of the OEM units for GM. I use to work for Eaton Cutler Hammer electrical division and that was a very good company to work for. As an employee you could "order" any Eaton product (even rearends) from any Eaton Division and they would put it on a truck route to your factory and you paid zero shipping and got the part, unit, system, whatever AT COST! They made generators, PLC's, UPS's, Automotive stuff, circuit breakers, breaker panels, you name it. This was back in 2005-2006.
 
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asand

asand

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Worked on the jig a little more. Bushing mounts welded in. Pasenger side pad next.20240915_165035.jpg
 
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asand

asand

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Picked up a 28 spline Crown Vic 8.8 rear end. Escalade inner axles spline in to the 8.8 diff like they were made for each other.20240923_123722.jpg20240923_123735.jpg
 

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