I had a friend put my 4:10 gears in, and Iwas wondering how much play you should have when say your car is on jacks, in neutral and you turn the driveshaft. how far should it turn before the wheels turn. I have about 1/2" of play inbetween turning the driveshaft right or left. I also can pull it out towards the front of the car about 1/8". does that sound right. I hear some loud bangs or pops, mainly when shifting from 1st to second, and occasionally 2nd to 3rd, under full throttle. Some of the popping might be due to my dumped flows, but the noise comes from the rear. Just curious. when we did the install, we used the same spacer that was on it from the factory. a local machine shop that did the pressing recommended that. Thanks, chris