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Discussion Starter · #1 ·
I have this 31 spline posi. Looking at the pic you will see a ecliptic hole at the end of the pen. Its between the ring mount bolts. In some other spots it looks like its starting to come through also. It looks like there is some kind of washer inside the hole that moves when I push on it with the pen tip. Is there something on the inside of the posi unit that wears through on these spots? Or is this just a bad casting? Any opinions are wanted, Thanks in advance...
http://a3.cpimg.com/image/CF/61/11470543-74e7-028001E0-.jpg
 

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You have discovered why the short side case of the TractionLok is prone to break under hard use.
Inside the case half is where the clutch plates sit. The plates turn with the case because they have four tabs sticking out of them that fit into four slots insdie the case. When these tab slots are machined into the case half, sometimes the machining breaks through the metal of the case. That is the crack you are seeing. There are four steel metal pieces that fit inside these cutouts and hold the clutch plates in place. These are the "washers" you are seeing move.
Because this machining weakens the strength of the casting, it is here that a TractionLok will break, tearing the center out of the hub around these bolts.
All TractionLoks are like this. You may have seen HD versions of this side of the casing sold to prevent breakage. These HD pieces have extra metal so that the machining doesn't weaken them as much. I don't know if these HD case pieces are available any more.
Most TractionLoks can handle great stress, but big horsepower and good traction can kill them in time.
 

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Discussion Starter · #3 ·
Thank you very much....everyone learn from this!!! When I bought this thing tonight, the guy on the phone told me it was a 9" 31 spline 3:50 geared posi. I drove 2 hours round trip to get the dang thing only to find out it was a 3:25 gearing. Not what I wanted. Ticked off I bought it anyway because I made the trip in 104 degree heat and wanted something out of it. I always check these suckers out for bad gears, slop, bad bearings, AND cracks between the ring bolts. But this time the guy was right there telling me all his project car stories and I missed the little hole. Now I will try to sell this unit to anyone who understands that he should be running an automatic or a mild motor or even stock. Anyone interested just give me an e-mail...Thanks again.
 

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You can buy a new cover from 9+ or Currie and they are much stronger. The price is around $140.
 

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If it isn't cracked or broken then run it,those holes are in all those cases, Ford put those in all the HIGH horsepower cars only and trucks ,,so Ford knew it would take a beating,,yes they have been known to break but so has titanium Myself and most people run them with NO problem,,sell it only if you want to buy a detroit locker or a spool not because it is weak
 
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