Sure-grip cone style driving characteristics ?

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DrEamer

I suffer from cars on the brain!
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I finally dug into my 8 3/4 to see what I had, only to be a little surprised to find a cone style Sure-grip. The car is a base 73 Challenger, so a limited slip sort of seemed out of place, but I won't complain. So, for those that have driven them, are there any complaints? I know it is not as favored as the clutch style, but if it turns out to be in good usable shape, it would save money for other things that the car needs. If the cones does not need rebuilding, I will be into it for around $450 with new gears, rebuild kit and labor.
 
They are good performers. Their only drawback is that they are not supposed to be rebuilt. For all the times that I have heard that fact, I personally have never wore out a clutch type. I've bought them and had them replaced just to get it done but I've never bashed any car hard enough, long enough to wear one out.
When they wear out, they act like a regular open diff.
 
been using 1 cone type and one clutch type in 2 Darts for 30 years. They drive the same as far as I can tell. The clutch type got rebuilt 5 years ago and I just know when the cone type goes, I'm on the hook for a new one, but after 30 plus years who could complain...
 
I do believe rusty rat rod can rebuild the cone units. It ain't the best to cut down the cones and shim it, but it ain't the best to blow money on new parts either.

The diff in my Dakota will chatter now and again, but overall, it's a seamless unit.
 
If you set them up right they work real snazy. On the street I sorta favor them. They are hard to wear out if you use the proper fluids, and don't peg-leg them. But once the Grip is gone out of the Suregrip, you can destroy them in a few minutes.
After restoring the unit to operation, I set mine up to a turning torque of 100 minimum to 120 preferred, ftlbs, with everything lubed up with the fluid cocktail I want to run.
120 is too much with skinny tires, and the inside tire will not stay in contact with the road, but will slip and squeal.
100 is not enough with wide or sticky tires, and on some situations , one or the other, tire will slip.
120 is just right for my 295/50-15 BFGs or Coopers, samechit to the SG.
130 is getting to act like a spool, and with 295s,I don't like it.
You'll know when it's just right, when you can come into a turn a lil too hot, in first gear,and she starts to push; but you lay on the gaspedal and the back end steers her back onto the road before you went off-roading, which usually ends poorly, or at the least, embarrassingly. Peg-legging won't do that, and a spool will push you right into the ditch.
Well maybe it's just me, that gets pushed,lol.
I see zero problems with rebuilt cone-types. I even got a machine shop to restore the cross-pin saddles, of some of my units. I've even had to clean up the clutch surfaces, of both the cases and the cones.
But there comes a day when the cones have been machined so many times that I just gotta wonder if they will still brake my 295s. So far so good.......
I have thrown away cones, spiders and pins, but never a case.

BTW; if you peg-leg them,eventually the crosspin likes to try to seize in the spiders, and ends up tearing chunks out of the spiders, twists off the crosspin retaining screw, and then trys to vacate the differential thru the backside; but I've never seen one be successful. When that happens, everything just stops turning, and you are skating; best rear brakes ever.
 
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When that happens, everything just stops turning, and you are skating; best rear brakes ever.
Did that at 45 mph with a 70 Ford F250. Full rear end lockup, starts getting sideways, all the time my brain was trying to process what the hell is going on. Shaft brakes and rear freewheels. Streightens up, coast into gas station.

30 seconds earlier I was doing 70 on the Fwy.
 
Hyup when someting like that happens, my brain goes 90mph trying to process what to do next, but it's never fast enough, cuz even at just 45 mph, my car is traveling at 66 feet per second. Up here the hiways are 12ft wide per lane, and even if you have practiced such a thing;on a 2-lane, a half second reaction time could already put me; backwards, upside down, and on fire.(John Force).
Glad you lived.
 
Thanks for the responses. I'll have to try to get the unit apart over the next few days to see what the cones look like. Then I may have a few more questions.
 
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