489 Rear Diff Convert to Posi

[Go Fly]

i have an open 489 and would like to convert to posi if possible or cost effective.

For a 68 Super Bee.

 

[WP29440SE]

what the hell is a posi

 

[Kern Dog]

 

[mopar 3 B]

impossible to convert to a posi

 

[NoCar2023]

https://www.quickperformance.com/Chrysler-8-34-Sure-Grip-Power-Lock-Posi-Unit_p_20442.html


Damn, these things are pricey....maybe search ebay for a used one.
Here is one from Dr Diff.

https://www.ebay.com/itm/Chrysler-Mopar-8-3-4-8-75-Power-lock-Clutch-Sure-Grip-Posi-Fully-Machined-New-/173833672012 View attachment 737467

 

[NoCar2023]

Here is another option.


https://www.summitracing.com/parts/...GJWu5CPaU8nru_GUibcf-mnQ_gqYPdwxoCFsAQAvD_BwE

 

[66Satellite47]

No problem converting the open to a limited slip of one sort or another. Two options for OEM, early Dana style clutch or the newer cone style. I like the early style, rebuildable version. Aftermarket versions may be a good choice. Seems like aftermarket prices are pretty good. But check with an expert, Dr. Diff?

 

[Go Fly]

Brutal

But deserved. Sorry gang it’s a sure grip.

 

[chtampa]

Isn't the Dana called a Power Loc?

 

[Frank Mopar]

Here is another option.

View attachment 737468
https://www.summitracing.com/parts/...GJWu5CPaU8nru_GUibcf-mnQ_gqYPdwxoCFsAQAvD_BwE

I have one of these setups in my car. Shes has a make a pretty loud clicking noise when turning which is normal. I always get the “somethings wrong with your rear end” comment but When you mash the gas both side hook no problem

Would I put another in? Nope.

 

[66Satellite47]

Used in earlier 8 3/4"s. Same style as in the Dana 60. I like the re-buildible design.

 

[NoCar2023]

• American Motors: Twin-Grip
• Buick: Positive Traction. Gran Sport models used the term "Limited-slip (differential)"
• Cadillac: Controlled
• Chevrolet/GMC: Positraction
• Chrysler: Sure Grip
• Dana Holding Corporation:Trak-Lok or Powr-Lok
• Eaton: No Spin
• Ford: Equa-Lock and Traction-Lok
• Jeep: Trac-Lok (clutch-type mechanical), Tru-Lok (gear-type mechanical), and Vari-Lok (gerotor pump), Power Lok
• Oldsmobile: Anti-Spin
• Pontiac: Safe-T-Track
• Studebaker-Packard Corporation: Twin Traction
• Yukon Gear & Axle: Duragrip
• Many of our fellow enthusiast: (including Differential suppliers) "Posi"

 

[Cranky]

The newer style cone SG can be machined once it quits working but it needs to be done right away instead of just hammering it trying to make it work.....because that won't happen. I've done many of them over the years and then they are good again for many more years. The main thing I don't care about the early 8 3/4 style SG is the smallish center thrust pin and the smallish spiders. Generally, the center pin gets messed up because of improper axle adjustment and isn't strong enough to take much improper adjustment. The cone unit has a much larger center pin and can take it plus it's trapped in place unlike the Power Lok. Also, the Dana 60 PL is a much larger unit than the 8 3/4 unit.