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  • 1965 - 1973 Classic Mustangs -General/Talk-
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posi or open?

  • Thread starter Thread starter calpolymustang
  • Start date Start date Feb 19, 2004

calpolymustang

Member
Feb 1, 2004
217
0
16
Santa Rosa, CA
Feb 19, 2004
#1
  • Feb 19, 2004
  • #1
how do i test a rear end for posi/lim.slip/open at the junk yard?

i found a 9" thats 55" drum plate to drum plate (~56" housing). i counted 3.5 pinion turns for one axel turn, but that was without holding the other end. when i turned one axel, the other side turned the same direction. the guy wants $220 for the setup, but i dont want to buy it unless its worth the trouble of hauling home. i already have a 31-spline galaxy 9" i can shorten
 
F

Fostang

Founding Member
May 8, 2002
1,400
0
36
Stockton, Ca
Feb 19, 2004
#2
  • Feb 19, 2004
  • #2
if they both spins in the same direction it's got the posi or some f'd up spider gears. LOL

Good luck.
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
3
77
lubbock, texas
Feb 19, 2004
#3
  • Feb 19, 2004
  • #3
if both axles turn the same direction it is indeed a posi, barring any mechanical failures in the diff itself
 

SandSprite

Member
Feb 8, 2003
332
0
16
L.A., CA
Feb 19, 2004
#4
  • Feb 19, 2004
  • #4
Where's this one at? Is it 55" backing plate to backing plate? If so that will be too wide. 65-66 are 52.25" backing plate to backing plate and 57.25" drum face to drum face. What's wrong with that 8"?

The way i saw that my 9" was a LSD first was by the tag. The tag will have a '.' for the ratio, i.e. 3.50. A trac-lock will have an 'L', i.e. 3L50.
As mentioned, spinning one side and having the other side go the same way indicates a LSD too.
 
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