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  • 1965 - 1973 Classic Mustangs -General/Talk-
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friction loc Rear?

  • Thread starter Thread starter egraz21
  • Start date Start date Mar 2, 2004
E

egraz21

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Feb 17, 2004
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Mar 2, 2004
#1
  • Mar 2, 2004
  • #1
How do I determine if my rear is a friction loc (both with the driveshaft installed and without if there is a difference)?
 
G

GaPonyFarm

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Jan 2, 2004
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Columbus, GA
Mar 2, 2004
#2
  • Mar 2, 2004
  • #2
Do you mean trac-lok? If you're asking how to tell if you have posi-trac, in one of its many forms, you need to get both rear tires up off the ground. Turn one of the tires and watch the other, if they turn the same direction, you have a posi-trac differential, if the turn opposite directions, you have an open, or conventional, differential.

Hope this helps!
 

mfp4073

Founding Member
Mar 14, 2001
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Hells Ditch, FL
Mar 3, 2004
#3
  • Mar 3, 2004
  • #3
GaPonyFarm said:
Do you mean trac-lok? If you're asking how to tell if you have posi-trac, in one of its many forms, you need to get both rear tires up off the ground. Turn one of the tires and watch the other, if they turn the same direction, you have a posi-trac differential, if the turn opposite directions, you have an open, or conventional, differential.

Hope this helps!
Click to expand...


I think you could call an traction loc a friction lock....makes sense as its a clutching type mechanism. I dont know if you were just looking to find out if the car has a traction loc or a detroit locker or just looking to find if its an open or a locker rear.
 
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D.Hearne

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Sep 29, 2000
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south louisiana
Mar 3, 2004
#4
  • Mar 3, 2004
  • #4
If it's a Detroit Locker, the wheels will turn in opposite directions when turned, like an open diff. Only when you hold one, the other won't turn.
 

mfp4073

Founding Member
Mar 14, 2001
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Hells Ditch, FL
Mar 3, 2004
#5
  • Mar 3, 2004
  • #5
D.Hearne said:
If it's a Detroit Locker, the wheels will turn in opposite directions when turned, like an open diff. Only when you hold one, the other won't turn.
Click to expand...

Huh, never knew that!
 
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egraz21

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Feb 17, 2004
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Mar 3, 2004
#6
  • Mar 3, 2004
  • #6
Thanks for the info. I wasn't aware that the Detroit Locker turned in the opposite direction like an open rear. I do wonder though, for the traction-loc rear does it matter if the driveshaft is connected and in gear (i.e. input yoke on pumpkin locked from turning) or unconnected (or trans. in neutral, input yoke can turn)?
 

mfp4073

Founding Member
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Hells Ditch, FL
Mar 3, 2004
#7
  • Mar 3, 2004
  • #7
No, if its connected and in gear NOTHING moves! Do it with the car out of gear, driveshaft connection does not matter at that point.
 
G

GaPonyFarm

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Mar 4, 2004
#8
  • Mar 4, 2004
  • #8
D.Hearne said:
If it's a Detroit Locker, the wheels will turn in opposite directions when turned, like an open diff. Only when you hold one, the other won't turn.
Click to expand...

That's odd... My Detroit Lockers turn the same way... Currie Enterprises 9" Plus w/ Detroit Lockers...
 
D

D.Hearne

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Sep 29, 2000
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south louisiana
Mar 4, 2004
#9
  • Mar 4, 2004
  • #9
The one I have in my 68 Moneterey doesn't. At least I'm 90 percent sure that's what it is. I pulled it out of a 57-59 Ford 9 inch, that was under a 66 Stang parts car. I'm beginning to wonder if the 88 Lincoln Mark VII I just bought has on too. It's got a posi in it, and acts just like the one in my Monterey. Jack it up, and hold the tire on one side and you can't turn the other. But rotate them without holding them and they spin opposite each other like an open diff. And both have a soft clicking sound when spinning them, like a rachet. Maybe I'm wrong though and they could be something besides Detriot Lockers.
 
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