I put the front diff in an aluminum case and turned it by hand, still noisy. I replaced the pinion bearings and that made no difference. Then I put the front pinion on the rear diff and it was a little noisy but not too bad. With the rear pinion on the front diff it was still rather noisy. Going to order a new ring gear (already got a pinion on order) and hopefully that will get it running right again and hold together for a while. I'm up to about $65 worth of parts not including the ring gear and I don't have a job anymore