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489 Posi?

I was just thinking it would be a way to tell if the clutches need replacing without disassembly. It's stating that any measurement over .010 would indicate worn clutches.

From the 1962 FSM
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Guess I need to take another look at how these things setup and take a look at the FSM's I have. Wouldn't think the 1962 manual would be different than one from 67 or older? I've always checked them with the T handles to make sure they actually grab and use a mix of rear end oil and STP as assembly lube. You would think the STP would make things more slippery but it's been a life saver for the POS Track Lok in my 2000 Durango vs the factory AND Ford LSD additive. Many times the FSM doesn't make sense to me but it's been several years since building a clutch type SG. I also just stuck a .005 feeler into that unit on the shelf and it was snug but it went in. On the other hand, I would have thought less meant more wear. Think I'll take this thing apart and remove a plate and see what it does. It just seems opposite logic to me lol

I just went and looked at it. It was a 489 cone type. Gear wear looked good.
Pinion play was minable. Had just a few specks of surface rust. He wanted
$300 for it, but I didn't buy it because it was a cone type.
300? What gear does it have? Surface rust on the gears? I've run gears that sat for years in a junk car or truck and the gears were very pitted but they still ran great. Just got to clean them up and get rid of the scale. Over the years, I sold all the clutch type units I got and kept the cone units for me because no one wanted the cone SG's but I've never had any issues with them even running 11's at the track. I also know how to breathe new live into the ones that were not totally wasted. The cones can be bottomed out so long as some moron didn't keep on hammering on it trying to make it lock up. When you do that, it just kills everything else inside of it. You can also check to see if the unit is still tight with a couple of axles and pry bars but. The clutch type also has it's own set of issues and need to be looked at.....
 
300 is a good price on a 489 sure grip, I would've bought that on the spot
 
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