Posi vs Open

Nov 24, 2004 9 Replies

So without actually getting under the car and trying to find the stamp on the top of the axle tube, how do I know if I have an open or a Posi rear end?



Anyone have the math equation as to telling what gearing is there by jacking the car and counting tire rotation vs driveshaft rotation?



Its a 72 Lemans, 350 auto with 10 bolts in the rear cover.


Wm


With both rear tires off the ground, spin the d-shaft. If both tires turn in the same direction, then the diff is locking. If only one tire turns, or if they spin in opposite directions, the diff is "open". This is most likely the case on a non-GTO. GW

Or ... from a complete stop mash the gas pedal to the floor and release the brake pedal. Then count how many black marks are on the ground :-)

Someone, I think it was Dennis Smith, said something prolific. The following is not an example of that::

ONE! Right rear only.

Someone, I think it was Bryan Lee, said something prolific. The following is not an example of that::

Thanks! Guess what I'm doing after the tryptophan* wears off?

  • Thats the stuff in turkey that makes you sleepy ;)

You have an open "One Wheel Wonder" rear axle.

Someone, I think it was Dennis Smith, said something prolific. The following is not an example of that::

Oh joy oh joy.... Now lets see what the gear ratio is then...

Someone, I think it was Bryan Lee, said something prolific. The following is not an example of that::

Why would you ever think that? You've done nothing but help me, and I did say "Thanks!" :-)

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