Questions about rear end noise, wrong fluid and possible noise fix

[Bigham]

I already asked some questions about the noise in my 99 eddie bauer rear end and I have some more to go. I have been doing more research and I came up with more questions.

Two posts so far:
http://www.explorerforum.com/forums/showthread.php?t=383371

http://www.explorerforum.com/forums/showthread.php?t=382631

1-today I finally got to ride in the back seat and the whining seems to be coming from the right rear wheel, but it only makes the noise on accelaration, not when coasting. Does this mean it is related to the rear end?

2-I have the D code limited slip differential (4.0L SOHC, eddie bauer with tow package). the shop replaced the diff gasket and added 80/90 weight oil. Shouldnt it be the higer weight oil because it is limited slip?

3-When I take off I hear what sounds like a grinding noise. Could this be the clutch packs? Are there clutch packs in this year/model? If I replace with higher weight oil and friction modifier could this help with the noise and feel?

4-Should I replace the fluid and drive around for a while? I already know I have a leaking left wheel bearing seal. If I need to get the wheel bearings replaced, should I just wait and have shop do all the work at once?

 

[Bigham]

Between 50-60 mph the whining is brutal. If the radio is off it is all you can hear. If I am on the phone people always ask what the noise is!

 

[koda2000]

if you're hearing it on one side, it's probably the wheel bearing. change both rear wheel bearings and install new seals. then be sure to use full synthetic gear oil (of the correct weight) with a friction modifier.

 

[Bigham]

Had a shop put it on a rack and check it out. They told me the pinion was bad so it looks like I need to replace the entire rear end.

Anyone have the link to the rear end swap how to page? I spent and hour looking for it with pics and could not find it. maybe my search terms were incorrect..

I have a local junk yard with a replacement rear for $100 and will install it for $600. I have a friend that would help me install it for a case of beer. Hmm, which way to go???

 

[IAmTodd]

Proper gear oil for the LSD diff is 75W-140. Most are synthetic and include the friction modifier. The clutch packs will only make noise when turning (most likely under power).

Depending on your miles your clutch packs are probably shot by now.

 

[delexploder]

Rebuild it with new parts for less money instead of just putting another worn out one JMO

 

[Bigham]

How much would it cost, how involved is it and is there a thread with pics lurking on here?

 

[Robman]

I had the same issue when I bought my very first explorer(whining rear diff.) Drove me crazy and also felt like it was causing a drag on the vehicle. I was fortunate enough to strike a deal with a guy who was parting out his explorer so I just replaced the whole rear end.. same gearing of course (3.73) The pinion had alittle play in the newer diff going from forward to reverse but if you made the transition smoothly it wouldn't clunk. Other than that it was soo nice to have a proper functioning rear end. I feel your pain.. in the end I just ripped the sob out and replaced.