Rear end noise

[road2damascus]

Hello all. I have a rear end noise. I also have a passenger side rear CV boot leaking closest to the differential. It leaves a drip here and there and has been doing it for quite some time.

The hub on this side was replaced within the last two years so I doubt that is the noise. The differential is full of Amsoil 75 -140 and friction modifier up to the fill hole.

I have pressed on the E-brake while driving to make sure it is not sticking. The rear discs have been done as well.

My guess is the CV joint where the grease has leaked out of has dryed out enough to cause a grinding noise as the shaft is engaged?

What do you all think?

Can I just replace the CV boot and fill with grease instead of replacing the whole CV axle ($130)?

Thanks

 

[Limited02]

Describe your noise a little more. Does it whine only when accelerating and when you let off the gas at around 45mph, the sound goes away? If so, that would be your rear differential whining, which is a very common problem with 3.73 LS rearends on the Explorers. The fix is to rebuild it, but if you can live with the noise then there's no worries. Mine has been whining for the last 3 years and I haven't done anything about it other than changing out the differential with 85W-140 Synthetic plus friction modifier which makes it sound a little quieter.

Secondly, the leaking is most likely caused by the two-piece seal where the CV shaft enters the differential. Fords fix was a one-piece seal. I'll be doing that sometime in the near future because mine is doing the same thing.

 

[road2damascus]

The noise goes along with how fast the axle is turning. I go faster and the intervals get less.

wa----------wa--------wa------wa-----wa---wa--wa- wawawawawaw

1mph---------------------------------------------------30mph