Took my 06 GT to the shop last week to get some 4.10’s installed. After a couple days of issues (bad bearing, needing a new spring clip thing) they have said that my spider gears are worn and it is making some noise still. They want to either rebuild it, or swap it out with a new differential assembly. The Ford Performance one is only $260 so it isn’t crazy (they also recommended and Eaton for twice that) but I’m surprised to be having an issue with my diff as it only has 50k miles on it. I’ve owned it for the last 10k miles, so I can’t say what happened the first 40k, but the car is in overall great shape and the previous owner was an old guy who didn’t beat on it. Wondering if this seems reasonable or if they might be throwing parts at some other issue trying to fix it. Trying not to spend any more than I have to. The noise they were talking he said was due to a chattering in the spider gears that was causing “a whirring during decel, mostly over 45mph”. He said it either needs to be rebuilt or replaced. Thanks guys, let me know what you think. Also wondering if it is bad, should I stick with Ford or is it really worth it to spend more for an Eaton for a daily driver that sees little time racing.