What and where to order a sure grip

74delta

74delta

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1965 Chrysler 300 I want to make sure grip. Where would you guys order from and besides the unit what else would I need? Going to stay with the stock gearing. 742 case

20200815_132503.jpg
 
74delta said:
Is there anything else I would need to buy to make it work or just reuse the factory shimming and swap and ring gear over to it?
Click to expand...

Email the good doctor with your questions. Also ask about when they’ll be back in stock. The customer service would be worth the wait. Contact
 
twostick said:
He also has a helical gear type sure grip that is a little more money but technically speaking is a better differential. No clutches and no need for friction modifier oil additives.

And they're in stock...

Mopar 8 3/4" (8.75) Helical Gear Sure-Grip ("Sure-Trac")

Kevin
Click to expand...
Interesting. I'm not familiar with that style seems beefy. This is strictly a street cruiser that I want to be able to lay a good strip if I want to have some fun/stress relief. Think it's a good idea or over kill?
 
74delta said:
Interesting. I'm not familiar with that style seems beefy. This is strictly a street cruiser that I want to be able to lay a good strip if I want to have some fun/stress relief. Think it's a good idea or over kill?
Click to expand...

Don't quote me but I believe it is a Torsen style differential. They act like an open diff when cornering but lock up under torque. Unlike a Detroit Locker ratcheting diff, the Torsen does it seamlessly and silently.

The clutch type is more than adequate for your purpose but is apparently unavailable and you will never find better customer service than Dr. Diff. I've never seen a negative comment about him anywhere and there are people on forums I frequent that would ***** if their icecream was cold.

If you've never set up a diff before, be forewarned that there is a lot more to it than just installing it with the same shims etc that came out of the old one. It's not rocket science but it does require some precision assembly and measuring skills and tools.

If the added cost doesn't present a problem, I'd buy it from Cass, overkill or not. He will also have a complete kit to install it, bearings and all.

Kevin
 
twostick said:
Don't quote me but I believe it is a Torsen style differential. They act like an open diff when cornering but lock up under torque. Unlike a Detroit Locker ratcheting diff, the Torsen does it seamlessly and silently.

The clutch type is more than adequate for your purpose but is apparently unavailable and you will never find better customer service than Dr. Diff. I've never seen a negative comment about him anywhere and there are people on forums I frequent that would ***** if their icecream was cold.

If you've never set up a diff before, be forewarned that there is a lot more to it than just installing it with the same shims etc that came out of the old one. It's not rocket science but it does require some precision assembly and measuring skills and tools.

If the added cost doesn't present a problem, I'd buy it from Cass, overkill or not. He will also have a complete kit to install it, bearings and all.

Kevin
Click to expand...
Already emailing with him seems super nice. I think I'm going to go with what he says.
 
The differential "case" for an open differential is juat a "case" that the ring gear and spider gears, etc. are houwed in and the ring gear bolts onto. ANY time a case is changed, you'll need ro run a pattern on the ring gear with some "Gear Marking Compound" (which used to be lead-based). How to do this is in the FSM. You might do it with the factory shims to see where things are, but do NOT just swap the differential case without first doing a gear pattern check.

There is no real "dark science" in setting up a differential, but you might need some tools to do it right. PLUS possibly a high-torque means of removing the piniion nut!! Then re-torqueing it for the crush sleeve to do its thing. Your differential case supplier should be able to supply all that you'd need to do the job, I suspect.

The Torsen-style differential came out in about 1964 or so, as an upgrade for an open differential. Without the issues of the "locked until they unlock", spring-loaded clutches on the normal PosiTraction-style limited slips back then, which required the additive so they didn't "pop" on left hand turns.

The "Detroit Locker" is a positive-lock situation. When the shaft moves up the ramp, everything locks-up solid. Then unlocks when the shaft goes back to its "home position".

Just make sure you get the "OEM-spec" version limited slip rather than one of the lesser-versions of such.

Even with the OEM-spec item, you should br able to lay rubber on pavement as the wheel on "dirt" throws dirt, at the same time.

Keep us posted on your progress, please.
CBODY67
 
CBODY67 said:
The differential "case" for an open differential is juat a "case" that the ring gear and spider gears, etc. are houwed in and the ring gear bolts onto. ANY time a case is changed, you'll need ro run a pattern on the ring gear with some "Gear Marking Compound" (which used to be lead-based). How to do this is in the FSM. You might do it with the factory shims to see where things are, but do NOT just swap the differential case without first doing a gear pattern check.

There is no real "dark science" in setting up a differential, but you might need some tools to do it right. PLUS possibly a high-torque means of removing the piniion nut!! Then re-torqueing it for the crush sleeve to do its thing. Your differential case supplier should be able to supply all that you'd need to do the job, I suspect.

The Torsen-style differential came out in about 1964 or so, as an upgrade for an open differential. Without the issues of the "locked until they unlock", spring-loaded clutches on the normal PosiTraction-style limited slips back then, which required the additive so they didn't "pop" on left hand turns.

The "Detroit Locker" is a positive-lock situation. When the shaft moves up the ramp, everything locks-up solid. Then unlocks when the shaft goes back to its "home position".

Just make sure you get the "OEM-spec" version limited slip rather than one of the lesser-versions of such.

Even with the OEM-spec item, you should br able to lay rubber on pavement as the wheel on "dirt" throws dirt, at the same time.

Keep us posted on your progress, please.
CBODY67
Click to expand...
Just did some emailing back and forth with cass from dr. Diff and says if I'm just swapping in the suregrip unit should be straight forward just replace the carrier side bearings and swap over the ring gear. I will lay a pattern just incase but he seemed pretty confident.
 
Do yourself a favor. Just buy a complete 742 center section and bolt it in. I have 3 for sale.

thumbnail_20200225_103625.jpg


thumbnail_20200225_103631.jpg


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They are all Factory installed Dana power lock Sure-grips.Which were first installed in 1958 and used until 1972. The Borg Warner Sure grips "cone type" began use in late 1968. Dont buy them!
 
Do yourself a favor . Lookup Gary Lewallen .. AutoHobbyDigest Guide to the 8-3/4 . It is the best document to date.
 
Complete 742 suregrip center section with snubber and large yoke is 500.00 plus shipping. It weights about 87 pounds.
 
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