I wanting to know if these cars all came with posi rear end it came with a 305 tpi if this helps if not wat gears are recommended for daily driving but has good power

 

Look on your RPO code sheet (should either be under your center console lid or on the back of the lid on the lockable container in the trunk compartment) and look for G80. That will tell you if your car came with a limited slip differential or not. As for gears, the RPO labeled GUx will tell you what gears your car came with.

 

Jack both rear tires off the ground. Turn one and if the other turns the same direction its a posi if it turns the other direction it's not.

You can also count the number of drive shaft turns to one tire revolution and find out your gear ratio. If it's not a posi you need to hold one tire still when you do this.