Ben, did you ever get a chance to take any pics? Also, did you verify that the spline angle was indeed a match? This topic just came up on the XR4-Xtreme list as a possible concern - makes me wonder if perhaps GM used two different spline angles.DSPXR4ti wrote: This is the shims That I installed, no Pic's yet but I will building a spare.
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Brad
Hey Brad,
I saw that post and I tried to reply to Dan and you All to give him my input but it kick back to me, so I was going to email him today about my install/set up.
Ok..Spline angle? not sure what your asking here but here is what I did, took an input shaft from a spare diff. and put input shaft in the Eaton for a test fit, it had very little play, when I put the input shaft in the stock diff. it also had very little play at that point I found the LSD diff. for me.
I'm going to make a spare Eaton LSD diff. and I will take pic of the install, now that I have done this a time or two it go's a lot faster so keep your eye's open for my "Eaton LSD install" Thanks.
Ben
I saw that post and I tried to reply to Dan and you All to give him my input but it kick back to me, so I was going to email him today about my install/set up.
Ok..Spline angle? not sure what your asking here but here is what I did, took an input shaft from a spare diff. and put input shaft in the Eaton for a test fit, it had very little play, when I put the input shaft in the stock diff. it also had very little play at that point I found the LSD diff. for me.
I'm going to make a spare Eaton LSD diff. and I will take pic of the install, now that I have done this a time or two it go's a lot faster so keep your eye's open for my "Eaton LSD install" Thanks.
Ben
85 DSP XR4ti, 2009 Solo 2 National Champion, burns muffler, 3in exhaust, Mc2 Full suspension, 325 hps & 328tqr, GMR Intake, Wilwood brakes, Eaton LSD, stand alone ECU. Working on being SM National Champion.
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Ben, I'm referring to the angle at which the splines are machined into the stub-shaft and matching receivers in the differential. If you look back in this thread you'll see that JV raised this as a potential concern as did Harry on XR4-Xtreme. Luke understood the question and tried to take some pics documenting that they do match.DSPXR4ti wrote:Ok..Spline angle? not sure what your asking here
Bear in mind, it's possible that the splines could match (both are 26), and appear to be a proper fit, but you need to look close and see that the interface is flat and thorough in the "V" of the groove.
I'm wondering if perhaps some of the GM stuff was cut at 45 degrees and others cut at 30 (matching the Ford spec)? I'm sure someone who really knows GM rear-ends would know for sure.
Brad
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Ford is 45*PA. (Pressure angle---fancy schmantzy talk for the spline angle)DPDISXR4Ti wrote:I'm wondering if perhaps some of the GM stuff was cut at 45 degrees and others cut at 30 (matching the Ford spec)? I'm sure someone who really knows GM rear-ends would know for sure.DSPXR4ti wrote:Ok..Spline angle? not sure what your asking here
It's easy as pie to check.
Use the corner of a piece of ordinary paper, it's a nice 90* and should fill the spline. Best done on a OD, but with some scissors and some tape you could make a simple jig to hold the "gauge" to check IDs
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Damn it, that's what I get for taking someone's else word as fact rather than checking it myself.John V wrote:Ford is 45*PA. (Pressure angle---fancy schmantzy talk for the spline angle)
Yep, just recently had to do this when a part was incorrectly machined with a 82* counter-sink and the metric bolt just wasn't sitting right (Metric flat-heads have a 90* seat). Dropped the corner of my business card in the hole and saw daylight and confirmed it was wrong.John V wrote:It's easy as pie to check.
Use the corner of a piece of ordinary paper, it's a nice 90* and should fill the spline.
Brad
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That was my next question?DPDISXR4Ti wrote:Was this a stock GM Eaton you had in there?deathbypsi wrote:Here is what I found inside today.
Ben
85 DSP XR4ti, 2009 Solo 2 National Champion, burns muffler, 3in exhaust, Mc2 Full suspension, 325 hps & 328tqr, GMR Intake, Wilwood brakes, Eaton LSD, stand alone ECU. Working on being SM National Champion.
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Well you coulda just asked meDPDISXR4Ti wrote:Damn it, that's what I get for taking someone's else word as fact rather than checking it myself.John V wrote:Ford is 45*PA. (Pressure angle---fancy schmantzy talk for the spline angle)
I think, I can't recall exactly but I believe it was this spline thing that caused be to reject the GM thing way back in like 1988, just as the plunging tri-bearings was my reason to reject the Ford 8.8" IRS diff.
As second strike against both the GM and the Ford USA diff is the weaker "2 planet gear design which I won't use unless I have no other choice.
The Supra diff I prefer is of course a 4 planet design, and you needn't buy axles and adaptors costing HUNDREDS of dollars.