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Old 09-24-2002, 09:17 AM   #1
MITCH1914
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after this question about posi's i wont ask anohter about it

i need feedback on this. i think my truck may have a worn out posi. when i lift the truck up and turn the tires they turn opposite directions. when i play on the street and tap it from time to time both tires turn and chirp, but when i nail it only one tire breaks loose. so what gives do i have a posi that is worn out or do i have an open that turns both tires from time to time.

also when i go to the drag strip i have rubber inside of both wheel wells.

after this i will either buy new clutches or a protrack unit.

thanks

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Old 09-24-2002, 09:26 AM   #2
JimKshortstep4x4
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What happens when the truck is jacked up and you turn the driveshaft? If both wheels turn the same way, then you probably have a wornout possi, although this is not a positve test.

Jim
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Old 09-24-2002, 12:18 PM   #3
MITCH1914
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ANY EXPLANATION FOR THE OTHER TWO SITUATIONS I MENTIONED?

THANKS FOR YOUR REPLY
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Old 09-24-2002, 01:18 PM   #4
meathead95
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you have a worn out poi. if you turn one wheel and the other turns the opposite direction then you have a posi.
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Old 09-24-2002, 01:25 PM   #5
Michael A. K. G
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Quote:
Originally posted by meathead95
you have a worn out poi. if you turn one wheel and the other turns the opposite direction then you have a posi.
No. An open diff behaves this way also.

The ONLY way to tell the difference between a worn out Posi and an open diff is to remove the diff cover and see if you have clutches and a preload spring.
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Old 09-24-2002, 01:39 PM   #6
meathead95
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i have had 3 iroc's and 2 trucks with posi's and thats how they all worked turn one wheel one direction and the other spins the opposite
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Old 09-24-2002, 01:41 PM   #7
MITCH1914
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LAST QUESTION. SO IF I TAKE OFF THE COVER AND I SEE SPRINGS IN THE CARRIER IT IS A POSI RIGHT?

THANKS

Last edited by MITCH1914; 09-24-2002 at 01:46 PM.
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Old 09-24-2002, 03:53 PM   #8
Michael A. K. G
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Quote:
Originally posted by meathead95
i have had 3 iroc's and 2 trucks with posi's and thats how they all worked turn one wheel one direction and the other spins the opposite
Then both your Posi's were worn out. Positraction PREVENTS the wheels from turning the other way. Or did you leave the truck in gear when you did this? If so, you have a differential. All differentials (except for engaged lockers) do that. Posi's with effort (preferably a lot of it).
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Old 09-24-2002, 07:43 PM   #9
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MITCH1914 LAST QUESTION. SO IF I TAKE OFF THE COVER AND I SEE SPRINGS IN THE CARRIER IT IS A POSI RIGHT?
if you see springs and clutches it is most definitely a positraction axle. Mine is equipped and works properly and both tires turn same direction when spun on jacks.
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Old 09-24-2002, 07:43 PM   #10
72chevyLWB
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. The newer posi's like Gov-locks will allow one to turn one way and the other opposite. The are set up so when there is a certain amount of torque it will engage the clutch packs and allow both to spin, buy you can't do it by hand on a floor jack. The older ones like in our trucks (Eaton type) will spin both wheels the same direction. Most worn out units will allow both wheels to spin right off the line and then only let one spin after that. Your best bet would be to take 20 minutes to remove and put the cover back on to make sure if you have one or not. It sounds like you don't have one though. My 87 doesn't have one and when I powerstall sometimes it will spin both tires and every once in a while slide sideways. Just depends on what kind of traction you are getting. Hope this helps you out.
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