Posi-Traction

I have a 1969 with 350/350 and 4 speed (M20). Can't make out most of the
differential numbers, I believe it is a 3.36. Does anyone know how to tell
if positraction without disassembly or buring the tires??

Thanks in advance for any info.

Place a paint/chock mark on drive shaft. Place a second mark on the
top of your rear tire. Rotate the rear tire one complete revolution.
The number of time the driveshaft went around in that one turn of the
tire is your "gear number." For example, if you turned the tire
once and the drive shaft went aroud approx. three times and a third ...
you probably have a 3.36. Very careful when you do this and have
the motor OFF !!!

PS... up on jack stands ... if both rear wheels turn ... it's posi

In article >,
"Steve Land" > wrote:

> I have a 1969 with 350/350 and 4 speed (M20). Can't make out most of the
> differential numbers, I believe it is a 3.36. Does anyone know how to tell
> if positraction without disassembly or buring the tires??

Given that of the 38,762 '69s produced only 36,965 had Positraction...
Odds are yours has it.

If your true question is, "How can I tell what gear ratio my '69 has?",
you can jack it up and mark the drive shaft and tires, rotate the tires
counting the... etc. or you can sqiggle your way under it and look for
the code stamped into the bottom facing portion of the flange of the
gear case (assuming of course that no one has stuffed your case with
different gearing than the factory setup):

Small blocks:
AK - 3.36
AL - 3.08
AM - 3.36
AN - 3.55
AO - 3.70
AP - 4.11
AS - 3.70

For those with big blocks who come across this message in the ~future ~:
AT - 3.08
AU - 3.36
AV - 3.08
AW - 3.08
AY - 2.73
AZ - 3.55
FA - 3.70
FB - 4.11
FC - 4.56

If you have a very late production '69, you share the '70 rear axle
codes:
SB:
CAL - 3.08
CAM - 3.36
CAN - 3.55
CAO - 3.70
CAP - 4.11
CAS - 3.70
BB:
CAT - 3.08
CAU - 3.36
CAV - 3.08
CAW - 3.08
CAX - 3.36
CAY - 2.73
CAZ - 3.55
CFA - 3.70
CFB - 4.11
CFC - 4.56
CLR - 3.36

Here's waving to ya - \||||

Owen
___

'67BB & '72BB
___

"To know the world intimately is the beginning of caring."
-- Ann Hayman Zwinger

In article >,
"Steve Land" > wrote:

> I have a 1969 with 350/350 and 4 speed (M20). Can't make out most of the
> differential numbers, I believe it is a 3.36. Does anyone know how to tell
> if positraction without disassembly or buring the tires??
>
> Thanks in advance for any info.

Given that of the 38,762 '69s produced only 36,965 had Positraction...
Odds are yours has it.

If your true question is, "How can I tell what gear ratio my '69 has?",
you can jack it up and mark the drive shaft and tires, rotate the tires
counting the... etc. or you can sqiggle your way under it and look for
the code stamped into the bottom facing portion of the flange of the
gear case (assuming of course that no one has stuffed your case with
different gearing than the factory setup):

Small blocks:
AK - 3.36
AL - 3.08
AM - 3.36
AN - 3.55
AO - 3.70
AP - 4.11
AS - 3.70

For those with big blocks who come across this message in the ~future ~:
AT - 3.08
AU - 3.36
AV - 3.08
AW - 3.08
AY - 2.73
AZ - 3.55
FA - 3.70
FB - 4.11
FC - 4.56

If you have a very late production '69, you share the '70 rear axle
codes:
SB:
CAL - 3.08
CAM - 3.36
CAN - 3.55
CAO - 3.70
CAP - 4.11
CAS - 3.70
BB:
CAT - 3.08
CAU - 3.36
CAV - 3.08
CAW - 3.08
CAX - 3.36
CAY - 2.73
CAZ - 3.55
CFA - 3.70
CFB - 4.11
CFC - 4.56
CLR - 3.36

Here's waving to ya - \||||

Owen
___

'67BB & '72BB
___

"To know the world intimately is the beginning of caring."
-- Ann Hayman Zwinger

On Sun, 17 Apr 2005 22:41:34 -0400, (Edmond Doone)
wrote:

>PS... up on jack stands ... if both rear wheels turn ... it's posi

Use caution here, if you are supporting the car at the frame then the
A arms will fall to their lowest position cause they are hanging in
mid-air. This will put the axle universal joints at extreme angles and
can damage them if the drive train is rotated with the engine. But if
the diff. has a limited slip assembly in it when you jack both rear
tires off the ground, leave the trans in park if its auto, in 1st or
reverse if manual, engine off, parking brake released, turn the tire
on one side, if the differential is set up w/o limited slip the
opposite tire will rotate in the opposite direction of the one you are
turning by hand. but if the limited slip diff. has extreme wear on the
clutch pads it may give you the same result. Or if the tire will not
turn freely but rather has the feel of the car being in gear. its most
likley going to be limited slip.