POSI

[Jakes82]

im tired of just spinning one wheel all the time, so i think its time for positrack. This is about a 99% street car so i was wanting something that didnt lock both wheels all the time like in turns. im wondering do you have to buy a new posi rear end of just put something in the old one?
thanks for you help jake

[VileZambonie]

I prefer Auburn Pro series carriers myself. What is your truck? What rear axle do you have? What gear ratio do you have now?

[Jakes82]

i really dont know its a 82 chevy short stepside and is a 10 bolt but  i dont know ne thing else

[Fordeatinz71]

well, you will have to figure out your gear ratio to be able to order a posi.  you are most likely at around a 2.73 or so.  you might have as high as a 3.08 but you didn't see much higher than that in a stock 2wd 1/2 ton GM in that era...

[Captkaos]

I prefer the Eaton clutch type.

[mikeith]

i have an auburn prolocker w 3.73's and i love it.... never had the eaton one though but my 05 gto had a clutch type and it sucked half the time because it would lock up if i were going strait but 75% of the time when i tried get a lil sideways from a stop i'd get the dang 1 tire fire....

[avanti]

I don't mean to hijack the thread, but I have always wondered why some trucks just spin one wheel.
Is it supposed to do that?

[nova801428]

Spinning of one wheel is either an open differential or a really worn out limited slip.  Why not just get a locker?  Is a posi to chevy as a limited slip to a ford?

[Captkaos]

The majority of them have open differentials which is why only 1 wheel spins.  Adding a limited slip will transfer the power.

limited slip differential is the official name. 
in the past......
Chevy called it Positraction
Ford called it Trac-Lok
Pontiac called it Safe-T-Track
AMC called it Twin-Grip
Mopar called it Sure Grip
Oldsmobile called it Anti-Spin
Jeep called it Trac-Lok

[76_Scottsdale]

I was under the impression that a limited slip transfers power to the wheel with the most traction, instead of with a open axle where it transfers power to the wheel with least resistance.

[xtremjeepn]

ALL cars will come with some form of "Differential". Simply meaning the wheels on the same axle must be able to turn at different speeds while cornering.

The easiest way to do this is with an "open" differential.  This is the way most cars come. It allows all the power to go to the wheel with the LEAST grip. (makes for nice cornering for a street driver) It also allows the non spinning wheel to have lateral grip in a corner to add stability.

The next step up is a "Limited slip" or "Posi-traction" This is the same thing. It is achieved several different ways. Clutches or gears. It will send power to both wheels in more situations. In a HARD corner or with one wheel off the ground it will still send power to the wheel with the least grip.  This is better for street driving but not the best for off road.

The next step up is a "Locker" these come in two flavors "full time automatic" and "selectable".

A full time locker is a mechanical connection between the axles that will send power to the wheel with the MOST grip when you are OFF the throttle. As soon as you step on the gas it will lock both shafts together. These can be noisy on the street with banging and tire chirping. They are GREAT off road since you get traction even with a tire in the air.

A "selectable locker" is just that. You can turn it on or off. Typically an "open" or "limited slip" when off and a full "Spool" when locked. Great for an off/on road rig.

A "spool" is a solid connection between the shafts that gives NO differentiation at all. Both wheels are locked together ALL the time! These are great for drag cars and off road only rigs. They are VERY hard on axle shafts and tires if driven on the street. Not to mention it makes if harder to steer.

[okiesinmt]

Has anybody used or heard anything about powertrax?

Sean

[xtremjeepn]

I used a Powertrax "no slip" in my Jeep TJ. I broke 3 of them and eventually the carrier itself broke in half.  I am pretty light on the throttle too.  So I have no love for them.  I replaced the powertrax with a full case Detroit locker and never had an issue. It was a little clunky on the street but bombproof. I eventually built a full custom rear axle for the Jeep and installed a Eaton E-locker in it. (Selectable locker) Love it.

I just (yesterday) got the Detroit locker for my K30 Crew Cab 14 bolt.  I will be installing it today.

[81Cheyenne]

im tired of just spinning one wheel all the time, so i think its time for positrack. This is about a 99% street car so i was wanting something that didnt lock both wheels all the time like in turns. im wondering do you have to buy a new posi rear end of just put something in the old one?
thanks for you help jake

Looking back to Jakes' original question, I'm wondering the same thing.  I have a 81' C10 LWB 10 bolt and I'm assuming a 2.73 since the code says "standard ratio".  What's the most cost effective way to go Limited Slip?  The truck will be used for street and possibly get and upgrade to a 383 in the future. It has a 305 4Bbl now with intake,headers,etc. I'm planning to pull small campers/boats with it. I'd like the extra traction on steep boat ramps.

[VileZambonie]

Your best bet would be a clutch type limited slip. However if you're going to go that route now's a good time to change the ring and pinion and junk that 2.73 There really is no "cost effective" method. You'll need to buy the carrier, ring and pinion, crush sleeve, bearings, seals, selectable shim assortment, and limited slip oil (or additive)