rear end troubles

[mustangkid2.3]

i remember in a post a while back about rear ends, and a little test to see if yours was going out was to drive up into 5th gear, and let the car coast back down to 45 mph and then step on the gas, and if you heard/felt a bang come from the back yours was going on its way out? is this true? i can get this in 3rd gear and up. if so, what is composed of the rear end alltogether and repairing or replacing it? if need it be replaced, any suggestions on where i should go to get one. a better performing one than the car came with too.

 

[GTPhreak]

it is probably something simple like just the u-joints or something

 

[MSM0075]

Yeah lol.

I never heard of this "bang" noise comming from the rear. I just now if your going to slow in a low gear, you'll get a vibration feeling/noise untill it has enough strength.

 

[85 Coupe 5.0]

i have never heard of that test.

I would have to agree that if the u-joints are wore that can cause some slack in the driveline resulting in the noise you are talking about. It can also have slack from worn gears. I have that problem on my '85. The rearend has about 200K or so on the stock gears, and i can get a slight pop when i'm in 5th and mash on it, but that's because the gears are so wore the backlash has increased because of them wearing out. I took the differential cover off and inspected them and they were fine, just a little too much backlash. I suppose this could eventually destroy them by them clashing together eventually, but they have been fine for 3 years now that way, this includes launches at the dragstrip and just not being easy on it in general.

I'd say unless it's wining real loud or popping when you take off from a light or something, and the u joints are good, then i'd probably start to worry.