The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 09-24-2002, 09:17 AM   #1
MITCH1914
Registered User
 
MITCH1914's Avatar
 
Join Date: Mar 2001
Location: indianapolis,indiana,usa
Posts: 506
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

68 chevy C10 3.73
MITCH1914 is offline   Reply With Quote
Old 09-24-2002, 09:26 AM   #2
JimKshortstep4x4
Senior Member
 
Join Date: Jul 2001
Location: Muskegon,MI,USA
Posts: 6,026
Smile

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
JimKshortstep4x4 is offline   Reply With Quote
Old 09-24-2002, 12:18 PM   #3
MITCH1914
Registered User
 
MITCH1914's Avatar
 
Join Date: Mar 2001
Location: indianapolis,indiana,usa
Posts: 506
ANY EXPLANATION FOR THE OTHER TWO SITUATIONS I MENTIONED?

THANKS FOR YOUR REPLY
MITCH1914 is offline   Reply With Quote
Old 09-24-2002, 01:18 PM   #4
meathead95
computer illiterate
 
meathead95's Avatar
 
Join Date: Jan 2001
Location: Des Moines, IA
Posts: 6,440
you have a worn out poi. if you turn one wheel and the other turns the opposite direction then you have a posi.
__________________
72 2wd blazer
72 swb 4x4
meathead95 is offline   Reply With Quote
Old 09-24-2002, 01:25 PM   #5
Michael A. K. G
Registered User
 
Join Date: Jul 2002
Location: California central coast
Posts: 126
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.
Michael A. K. G is offline   Reply With Quote
Old 09-24-2002, 01:39 PM   #6
meathead95
computer illiterate
 
meathead95's Avatar
 
Join Date: Jan 2001
Location: Des Moines, IA
Posts: 6,440
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
__________________
72 2wd blazer
72 swb 4x4
meathead95 is offline   Reply With Quote
Old 09-24-2002, 01:41 PM   #7
MITCH1914
Registered User
 
MITCH1914's Avatar
 
Join Date: Mar 2001
Location: indianapolis,indiana,usa
Posts: 506
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.
MITCH1914 is offline   Reply With Quote
Old 09-24-2002, 03:53 PM   #8
Michael A. K. G
Registered User
 
Join Date: Jul 2002
Location: California central coast
Posts: 126
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).
Michael A. K. G is offline   Reply With Quote
Old 09-24-2002, 07:43 PM   #9
Gene
Registered User
 
Gene's Avatar
 
Join Date: Aug 2002
Location: Muskogee, Oklahoma
Posts: 2,914
Quote:
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.
__________________
1971 SWB 4X4 Build


BOARD MEMBER #5448


BOOMER SOONER!!!!
Gene is offline   Reply With Quote
Old 09-24-2002, 07:43 PM   #10
72chevyLWB
Got 20's????
 
72chevyLWB's Avatar
 
Join Date: Oct 2001
Location: Aberdeen SD
Posts: 1,451
. 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.
__________________
99 Silverado Ex-Cab 2wd, Bagged&WhippleCharged
02 Sierra Ex-Cab 4wd 2500 HD
The 72 went down the road.
72chevyLWB is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:22 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com