Really? Basic question about my rear end....


Oct 26, 2018
FarEast TN
Ha! That title might get wrong kind of attention! Anyway, I've been away from any forums for a while due to serious health issues so sorry but it was unavoidable!

I would like to ask you all' a question, it is a basic question about a 2000 mustang I bought for a parts car. This one is also a 6 cylinder automatic trans with a differential that is 'open', ie not a posi or limited slip. I had been driving a bit and noticed it had some what is sometimes called 'spring wrap'. It also was making what vaguely sounded like a brake grinding but not quite, in fact I had never heard anything like the noise it was making. Stumped I called the 'mobile mechanic' because not onnly was the noise etc completely new to me, I am in a wheel chair as well. Well, the first thing ethe mech did was jacked the car up leaving one back tire on the ground. He said 'here is your problem' and spun the tire/wheel on the lifted side, 'see that'?' Of course I answered saying one wheel supposed to spin cause it's an open diff! No, he replied the yoke isn't spinning, the diff is trashed.

But, I drove it to where it was parked, there was no slipping etc. just the noise and the spring wrap thing. Also he wanted a premium price for labor to replace the diff assembly with a used piece. So do you guys think he was on the up and up? He has been honest on the last two little jobs he done for mebut I cant afford to make a mistake. Thanks for hearing my crying!
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If the car is in park the driveshaft can't spin, even with both wheels in the air. If diff shot, you shouldn't be able to drive (a non posi car) because diff would drive the side of least resistance (the broken side). "Spring wrap" was a leaf spring thing, your car has coil springs. If the belief is that, I would say your rear end bushings are toast (uppers or lowers or both) as this would give similar rear end rotation that spring wrap did.

Any vibration or grinding when accelerating or decelerating? If so, it could be u-joints (noise/vibration would be loading or unloading the u-joint bearings) and if bushing are toast, added load and wear would be happening to u-joints as well.
Thanks Krusier! I just needed to hear that from some one else! I learned how to set up a diff ring and pinion etc in school long ago and it's too labor intensive to pay shop labor to have it done. So with that in mind I bought a salvage piece. Thanks again for the advice!