rear end woes

Okay, maybe the pinion depth is off, but maybe the ring is too far from the pinion. Both would cause a whine on decell. That's why old rearends whine on decell; the side bearings are worn and allow the carrier to move away from the pinion. I threw a set of gears in my Aerostar four years ago cuz the 7.5 was blown and it's been whining on accel ever since; ring gear too close to the pinion. I'm gonna fix it one of these days tho.