strength of open diff 8 3/4?

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Just as strong as a cone-type ......... until you peg-leg it
The cone-type SureGrip can be found in all three Center Sections; and is the same two-pinion Unit
The open center is the also the same among the three. .
The Strongest is the 4-pinion Clutch-Type Trac-Loc. How much stronger? IDK but on the street, with street-tires, in stock tubs; I sure wouldn't go hunting for one ......
unless maybe I had Caltracs and a high-friction clutch..........
The basic differences between them all is the pinion size, and the bearings. With 7260 Joints, yur likely to break them first.
 
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Feels odd pulling a lockrite to go open diff, but the handling is too hairy. Or I'm getting too old.
No slicks or 4-speed, just street tires and occasional driving in the rain.
Thank you AJ! I'll have to let up when the peg leg starts smoking
 
65TerrorCuda said:
I'll have to let up when the peg leg starts smoking
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No, you better let up sooner. And put fresh good oil in it.
Here's what can and often does happen, when one wheel spins;
The first thing is that the spinning wheel is doing double whatever the speed-O says.
The second is that the differential case is also spinning double-speed.
And so, the oil is flung off the parts and heat starts to build on the cross-pin which at first just scores ,by transfer of metal, usually from the two pinions to the cross. Maybe you get away with it a few times.
Eventually, one of several things can and will happen;
the Pin will hammer out the pin-saddles. tear off the anchor-pin, and try to exit the Banjo out the back. I've never seen one come all the way out, which is a good thing cuz the gastank is right there and gas is allergic to hot flaming metal. But they do come part-way out which locks the rear up solid. If this happens at speed. you will very quickly be in a spin, and there is almost nothing you can do about it..
The other thing that happens, if the cross-pin does not come out, is that the pinion gears seize to the crosspin, making the diff act like a spool.
In both cases, at the worst, the guts are all junk. And you got to get a specialist to weld up the hole in the banjo.
At the best, if you can get it apart, maybe you can save the Crown/Pinion, and the housing

So then, my advice is to post up a want-ad for a SG, and get it set up.
If you have skinny tires or a small-tub car, then have it set up at about 90 to 100 ftlbs turning torque with the fluid you need to run and the correct ratio of Whale-oil .
If you have a stout 360 and enjoy sliding around corners, you can go up to 110.
If you have a big-tubbed car with 295s on it , then up to 120 but not more, or you will be back to spooling it.
 
Just don't do burnouts with the open differential, keep oil in it and it'll last forever. Burnouts spin only one wheel. That makes the spider gears spin about four times faster than they're designed to, they over heat and weld them selves to the cross shaft and then the shaft spins in the case and ruins the case.
 
I’m curious, does the lock right tend to act more like a spool than an open Diff? I’ve heard they tend to stay locked under power, even during turns.
 
Any time you're on the gas it's locked or close to it. Slow turns with almost zero throttle it'll behave until you touch that throttle. It's very sensitive.

Getting on and off the gas results in a tail wiggle that gets worse with speed. It's probably like a spool but I haven't owned one.
I've never gotten used to it

On the plus side, it looks almost brand new with 10k miles of use. It's heavy metal for sure
 
The Eaton Trutrak is whole lot better for putting power down while turning. You don't spin out. Talk to Dr. Diff.
 
I broke a set of spider gears with a slant six on an open 8.75 carrier.
 
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