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9" ls vs true trac vs detroit

eb-nutt1

Sr. Member
Joined
Apr 17, 2006
Messages
584
Building a 69 luber, 33x 10.50 mud terrain, 4.10 gearing...maybe 75/25 road-off road...no hard-core off road, have another eb for that...currently have a auburn LS in the 9", but re gearing from 3.50 to 4.10 and looking for opinions on the true trac type LS or detriot vs what is currently in it...the auburn LS is a spring loaded clutch style and has never been very good even when new...thinking of going worm gear for better lock up ability but never had any experience with them, have only used detriot or full spools in my other broncos.

Thanks,
Brian
 

Yeller

Contributor
Bronco Guru
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Mar 27, 2012
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Rogers County Oklahoma
True track all the way, very smooth and highly functional with a long life and no additional maintenance.

Although by your description the auburn will do what your describing, so the choice is yours.
 

SteveL

Huge chevy guy
Joined
Jun 24, 2001
Messages
11,252
True trak for your use. If you need more traction save up for an arb.
 

bmc69

Contributor
Bronco Guru
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Jun 11, 2004
Messages
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The Detroit Tru Track is far and away my favorite LS....with the Auburn a distant second and the rest not worth fooling with for the most part.

I've got an extra tight Auburn in the back of my '78 Bronco (10.25 Sterling) and had an Auburn in the 9" before that. Both function well..but both make a lot of angry noises after they are warmed up, mostly when reversing and turning at the same time. The True Trak...you never know its there.
 

bax

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Old Member
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Aug 22, 2005
Messages
14,036
I agree with the experts above. I ran a Detroit Locker and took it out and replaced it with a true trak. I got better street traction and less "excitement" on the street.
 

Broncobowsher

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Total hack
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Jun 4, 2002
Messages
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Good choice. True Trak has been a good choice for a long time. Torsen makes good stuff as well (I think they even invented the thing). Local transmission shop thinks Torque Worm is better. There are a few more as well. Any would be good in my book.
 

Timmy390

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Jan 1, 2011
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Conway, AR
make a lot of angry noises after they are warmed up
You should run a Spartan...Talk about ANGRY all the time....LOL

Love my Eaton TrueTrac...No clutches...no special additives....no noise...just works and works well

Tim
 
OP
OP
E

eb-nutt1

Sr. Member
Joined
Apr 17, 2006
Messages
584
The Detroit Tru Track is far and away my favorite LS....with the Auburn a distant second and the rest not worth fooling with for the most part.

I've got an extra tight Auburn in the back of my '78 Bronco (10.25 Sterling) and had an Auburn in the 9" before that. Both function well..but both make a lot of angry noises after they are warmed up, mostly when reversing and turning at the same time. The True Trak...you never know its there.

Funny you mention the angry noises, my dad built the 9" center about 20 years ago for a customer to go in a 71 mustang...he run it about 6 months and said it was to poppy, jerky and had my dad build a Xtra tight factory LS ...he gave us the center section and we installed in the 69 eb and it does the same thing you mentioned but you unload one tire slightly off road and it might as well be a open rear end.
 

Apogee

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Nov 26, 2005
Messages
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I like that the helical worm type limited slips don't require any friction modifiers in the oil and they don't wear like the friction-type units. Quaife and Torsen have been around forever, however the Eaton/Detroit tend to be much more cost effective and plenty strong, even with some cast internals. Another option would be the Strange S-Trac and if we include alternative designs, I'd like to try a Wavetrac in something at some point.
 

Yeller

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Not sure who made it, assuming AAM, but I had a ram 2500 with a factory helical gear style that did have to have friction modifier to not chatter. But it was a diesel and it was always pulling heavy. It was phenomenal in the performance department.
 

Apogee

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Messages
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Not sure who made it, assuming AAM, but I had a ram 2500 with a factory helical gear style that did have to have friction modifier to not chatter. But it was a diesel and it was always pulling heavy. It was phenomenal in the performance department.
Hmm...who told you it needed the friction modifier additive? I only ask because my friend had one in his Dodge 3500 with the AAM Ø11.5" differential called a Nitro Helix IIRC, and it just needed oil. Regardless, he loved his as well and was often hauling his boat in and out of the lake with it without issue.
 

Yeller

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Hmm...who told you it needed the friction modifier additive? I only ask because my friend had one in his Dodge 3500 with the AAM Ø11.5" differential called a Nitro Helix IIRC, and it just needed oil. Regardless, he loved his as well and was often hauling his boat in and out of the lake with it without issue.
Supposedly there was a TSB about it, had a friend that was a service writer at the time, whether it was official or just an in-house developed fix I don’t know. Changed the lube in it many times and had to add the modifier to keep it from chattering every time. I do agree and have owned 4 different AAM 11.5’s, 1 of them needed it and 3 of them did not. I’ve talked to a few with true tracks that needed it as well, it’s probably a low percentage.
 

jeffncs

Contributor
Sr. Member
Joined
May 4, 2004
Messages
778
Loc.
Raleigh, NC
As others have said…

True Trak - works as an open unless there’s traction loss. This makes it supremely versatile for well-mannered street driving and utility when needed off-road with no need to activate or do anything.
 

Broncobowsher

Contributor
Total hack
Joined
Jun 4, 2002
Messages
33,460
The worm style limited slips can work if you lift a tire. Ride the brakes a little will load up the diff and got both driving.
 
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