Posi locked up

[Camaross82]

I am getting to the point of getting my car driving again and have come across what may be an issue. I have a GM 12 bolt that was rebuilt with an eaton posi unit. The rearend was in the car before I removed the engine and transmission, and I had put about 100 miles on it or maybe less. Now that the motor is done the few short trips down the street and back the posi has been acting more like a spool. I have not given any power to it as the car has not been tuned yet. But it will be tuned friday. Before it is run on the dyno I want to make sure that it is ok so I dont do any dammage to it.

I have read some people say to just drive in figure eights until it loosens up.

Any words of wisdom would be appriciated.

Thanks,



Dallas

[Z06vet]

Make sure it has friction modifyer (posi additive) if its required. Then I would do some figure 8s until it feels like its freed up. I find when they sit for long periods the first few turns I take it feels like its chattering. Get it up to temp & hit the 8s, should be fine if it was felt good before sitting up.
Scott

[bryant]

eaton has 3 different spring packs for them. the heaviest one will behave like you describe.
definitely need to have friction modifier and eatons instructions say not to use synthetic gear oil either.

[Camaross82]

Thanks for the reply. I am running straight 90 wt oil. And I did put some additive in it. Would it hurt to put a little more in it?

[bryant]

another bottle couldnt hurt and try doing some slow figure 8 turns to really let it work into the clutches.