How to machine side gears on solid trac loc. - TCCoA Forums
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post #1 of 8 (permalink) Old 12-26-2009, 04:14 PM Thread Starter
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How to machine side gears on solid trac loc.

If I pick up a solid axle trac loc how do I machine it to work properly ? Pics would be a n awesome bonus.. And is it hard to do ??

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post #2 of 8 (permalink) Old 12-26-2009, 04:43 PM
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There is a diagram floating around on what needs done. It must be tough, I can't get any machine shops locally to tackle it. They are hardened gears, but I am going to take an afternoon and use a dremel and see what I can do. I know people have done it, but I don't feel good leaving the circlip off.

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post #3 of 8 (permalink) Old 12-26-2009, 06:36 PM
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You need to bevel the inside edge so that the circlip will compress when you go to pull the axle out. The easiest way would be to take a side gear and an inner axle joint and as soon as you slide it on you will see what needs to be beveled. By doing it out of the diff this way, you can use a pick to pull the circlip off, grind the inner part of the side gear, and retest it until you get it right.

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post #4 of 8 (permalink) Old 12-27-2009, 04:45 PM
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Here is what you need.

-----1993 Bird 5.0------
393 stroker, Vortech YSi, on E85
Lentech Strip Terminator & 4,000+ RPM stall converter
Detroit Locker with 3.55 gears.
17x9 Cobra Rs with 255/45/17 BFG KWDS
275/50/17 M&H DR on the rear

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post #5 of 8 (permalink) Old 12-27-2009, 09:36 PM
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Send an email to [email protected]. Mike rebuilds these and offered to machine the modification for me. It wasn't cheap though, you might be better off getting a IRS Trac-Lock.

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post #6 of 8 (permalink) Old 12-28-2009, 08:00 PM
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Alan @ machined mine down for me. He chucked them in a lathe and had them done in about 5 minutes while I watched.


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post #7 of 8 (permalink) Old 02-28-2019, 01:36 AM
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Just re-posting the drawing, I don't see it in the above posting anymore. Thankfully this guy saved it a few years ago: IRS | A Turn of the Nut
Attached Images
File Type: jpg irs-side-gear-5.jpg (75.0 KB, 24 views)
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post #8 of 8 (permalink) Old 02-28-2019, 07:54 AM
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That is good to have. I have a copy of it somewhere. The issue is, if you find an original 28 spline Trak-loc for sale, it's a crap shoot whether it's the newer style with beveled gears, or the older style without. They both have the same part #, IIRC it's M4204-F288.

I bought two off E-bay over a 6 month period, and ended up selling the one for the solid axle to a guy with a Crown Vic.


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