Posi's
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From: Houston, TX
Originally Posted by RTCXiR
Hello, when it comes to Posi units, whether they be clutch or gear, does anyone have a recommendation for a posi unit that is good all around whether it be on the street, mud or snow?
Last edited by KingRanch Glenn; Jan 28, 2007 at 11:08 PM.
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From: oceanside C.A.
Originally Posted by KingRanch Glenn
A good posi unit is the Tru Trac by Eaton. This is an all gear limited slip (posi) which has no clutches or cones. It requires no friction modifier added to the gear lube. This is a strong unit which should give you many years of trouble free service.
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From: Along Lake Erie
Originally Posted by bigtruck311
i agree but the unit is made by detriot
Here's the press release from the end of January, '06:
http://www.detroitlocker.com
(Notice the Eaton logo at the top)
EATON ADDS DETROIT BRANDS TO DIFFERENTIAL PRODUCT LINEUP
January 23, 2006
SOUTHFIELD, MICH. .Eaton Corporation, a diversified industrial manufacturer, is strengthening its presence in specialty vehicle markets with its recent acquisition of Tractech Holdings, Inc., the parent company of such well-known brands as Detroit Locker® and Detroit Truetrac®. These market-leading differentials will be sold alongside the Eaton Posi limited-slip differential and the Eaton Elocker electronic locking differential.
"We're the leading producer of differentials for original equipment applications and we saw an opportunity for growth in the performance aftermarket by increasing our product lineup," said Mary Jo Surges, general manager, Eaton Performance Products Division. "We now have a differential for every on-road or off-road need and we make the highest quality and most reliable differentials on the market today."
Eaton is a global company and as a leading manufacturer of original-equipment products it will utilize its global manufacturing capabilities to produce the Eaton and Detroit differentials. Engineering and design for all differentials have been integrated into Eaton's global engineering and research and development centers in Southfield and Marshall, Michigan. All product testing and validation will be conducted at Eaton's vast Proving Grounds in Marshall, Michigan, where it has complete on-road and off-road test tracks.
January 23, 2006
SOUTHFIELD, MICH. .Eaton Corporation, a diversified industrial manufacturer, is strengthening its presence in specialty vehicle markets with its recent acquisition of Tractech Holdings, Inc., the parent company of such well-known brands as Detroit Locker® and Detroit Truetrac®. These market-leading differentials will be sold alongside the Eaton Posi limited-slip differential and the Eaton Elocker electronic locking differential.
"We're the leading producer of differentials for original equipment applications and we saw an opportunity for growth in the performance aftermarket by increasing our product lineup," said Mary Jo Surges, general manager, Eaton Performance Products Division. "We now have a differential for every on-road or off-road need and we make the highest quality and most reliable differentials on the market today."
Eaton is a global company and as a leading manufacturer of original-equipment products it will utilize its global manufacturing capabilities to produce the Eaton and Detroit differentials. Engineering and design for all differentials have been integrated into Eaton's global engineering and research and development centers in Southfield and Marshall, Michigan. All product testing and validation will be conducted at Eaton's vast Proving Grounds in Marshall, Michigan, where it has complete on-road and off-road test tracks.
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From: Memphis, TN 38135, USA, Earth
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From: Along Lake Erie
IMHO, torque-biasing diffs are still llimited slips... they aren't lockers and they aren't open, and they *do* limit the slip of the low-mu wheel...
Splitting hairs though.... Regardless of what you call 'em, they work waaay, better than any clutch-based unit.
I want to know more about the new G-80 series Eaton LSDs... They featured them on Motorweek this weekend, but didn't show enough about the inner-workings to show how they work.
Splitting hairs though.... Regardless of what you call 'em, they work waaay, better than any clutch-based unit.
I want to know more about the new G-80 series Eaton LSDs... They featured them on Motorweek this weekend, but didn't show enough about the inner-workings to show how they work.
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From: Memphis, TN 38135, USA, Earth
If you click that link in my first post, you can see just how wide that hair is. 
It's like saying: a Ford truck is a Chevy truck. They're VERY different, both in form AND function.
It's like saying: a Ford truck is a Chevy truck. They're VERY different, both in form AND function.
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From: Summerville, SC
A better solution is to limit how fast the spider gears can turn by braking the axle gears - "limited slip". This involves simple springs pushing on friction materials inside the carrier, but sometimes requires additives to the oil. They also wear constantly, so they require service to continue to function. Also, they can be easily overwhelmed by wear, engine power, or driveline torque (big tires or a heavy vehicle). Some brands of LSD's are Ford's Trac-Loc, GM's Positraction, Dana's Hydra-Lok, and Auburn, and each uses a specific carrier different from the open diff's.
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From: Houston, TX
Originally Posted by chiefFX4
i rest my case
A few problems with the clutch or cone limited slip.
> They DO wear out. These will require rebuilds. One major manufacturer (forget which one) has a program where you send in your worn out posi and they will replace it with a rebuilt unit at a lower price than a new one. Don't expect a posi to give traction like new a few years after you own it. This is the reason for the rebuild program.
> Limited slip or posi will NEVER give anywhere close to 100% lock up. This is probably OK for a street vehicle, but is an awful solution for racing, a dedicated trail vehicle or a commercial truck. Doubt this, look at what racers-dirt to NASCAR- use, either a detroit locker or a spool. Because a limited slip will grenade or simply not function.
> Many years ago General Motors actually offered detroit locker as an option on commercial vehicles.
If I were going to add a limited slip aftermarket, I would use a tru trac (all gears) or one of the electric selectable lockers now available. Of course there is the ARB selectable air locker. Proven design, but expensive.