AAM 11.5" w/Anti-Spin (Worm Gear-Torsion) type gear set.

[PontiacHO]

You are probably thinking of the Detroit Locker.

Yep. It is truck stuff anyway. If it’s the same diff as in my GMC it is hit or miss locking both axles/wheels for traction.

 

[dfarr67]

I have read/been told the Eaton design (Anti-Spin) - worm gear/torsion type (Anti-Spin) needs a gear oil that does not contain the LS additive to perform as designed. (This unit is totally different then the Clutch Type).

Was curious if any member has experience with this?

It'd be a 'Detroit' designed TruTrack and Eaton bought them out years ago. I run a few of them and I prefer them over others. Detroit claimed they were designed and tested with dino oil- I run synthetic and wouldn't know the difference if it was delivering below spec.

 

[dfarr67]

Yep. It is truck stuff anyway. If it’s the same diff as in my GMC it is hit or miss locking both axles/wheels for traction.

Those 'auto locking' GM diff's are disposable, I've gone through three and I am by no means hard an my gear. Supposedly the 3/4 ton and up hang out- but the torsions are so much better.

 

[MattPersman]

Dealer tech here. For a 17 you can use either. They aren’t picky.

Mopar 75w85 is what they mostly call for that year 68210057AB on an 11.5 anti spin DSA.

If you haven’t had issues with that yet then keep using it.

 

[dnewton3]

Those 'auto locking' GM diff's are disposable, I've gone through three and I am by no means hard an my gear. Supposedly the 3/4 ton and up hang out- but the torsions are so much better.

The GM marketing name was the "Gov-Lok"
The inside joke was it was called the "Gov-Bomb"; they were known the not take any manner of abuse whatsoever without internal carnage.

 

[Greasymechtech]

Works better without LS additive but not critical for most. You can just tap the brakes for preload and it'll load up just fine.

The question you should ask the manufacturer is how much bias do you get with different gear oils. Most will be silent since they haven't compared conventional vs synth, both either with or without LS additives, to give you final diff capability results.

There is also the synth vs mineral hearsay that gets repeated excessively by the uninformed that think that synth is automatically more slippery.

Fear the super slippery synthetic... your helical gear diff won't work and your engine won't break-in properly

There are plenty of non-LS gear oils. Typical GL-5's used in Subaru manuals are another option... Redline NS, MPT NFM, Amsoil FGR/FGO, and Motul Gear 300... Several automakers also have non-LS gear oil options.

The Mack GO-J and Plus list are good starts but typically won't be found at walmart. Visit your local heavy truck repair center.
https://www.macktrucks.com/-/media/files/pv776-89149448.pdf?rev=fb15cfb8aa9a413d86600585090f770f

Plenty of equivalents and knock-offs... see the common synth and LS fear scare:
https://www.demandaam.com/technical...ite-gt-helical-gear-limited-slip-differential
https://www.powertrax.com/product-info/powertrax-grip-pro-traction-system/
https://nitro-gear.com/shop-by-category/traction/helix-helical-gear-limited-slip.html
https://www.quaife.co.uk/quaife-products/atb-limited-slip-differential/
https://www.usastandardgear.com/shop/sl-d30-4-27-lsd
https://torsen.com/
https://www.eaton.com/us/en-us/catalog/differentials/eaton-detroit-truetrac-differential.html
https://www.strangeengineering.net/...e-8-8-differential-helical-differential.html/

I believe the Torsen t2r and higher bias t2 uses spring/clutch preloaded for more friction and ability.

Maybe they should produce a traction additive... or use a thick sae250 for added fluid friction.

 

[DuckRyder]

I have a True Trac in the F100 it works well with Delvac 1 and has a relatively high bias...

Anti Spin is Mopar Lingo for any limited slip ...

G80 is the RPO code for a limited slip or locker - eaton posi is RPO G80, auburn cone clutch G80, eaton Gov loc G80 - i wish people would catch onto this and who ever at GM decided to call the Gov Loc "g80" in marketing should get the rack ...

 

[dfarr67]

The GM marketing name was the "Gov-Lok"
The inside joke was it was called the "Gov-Bomb"; they were known the not take any manner of abuse whatsoever without internal carnage.

Gov-lock, Cucko-lock, POS- whatever......and they made them for sooooo long.

Couple more names to throw into the mix.
Torsen Gleason
Diesel Kiki