8.8" rear noise on take off

[robertoa1a]

I have been noticing a slight scrubbing noise on acceleration from a dead stop. I notice it mostly when turning. '96 5.0 xlt 2wd 130k mile, towing package, 8.8" limited slip. The breaks checked good. No play on wheels. U-joint good. No slop on pinion as far as I can tell. Evidence of minor leakage on pinion inlet (dry). I doubt rear fluid was ever changed. If it was they provably didn't use limited slip juice.

Problem is small right now.

 

[storlied]

It COULD be your wheel bearing, checkout my thread here:

http://www.explorerforum.com/forums//showthread.php?t=226392

 

[robertoa1a]

Yes, I read your thread just before I posted mine. The diference is mine doesnt do it all the time and I don't think its a wheel bearing. I'll double check. I can't find any slop in anything.

 

[storlied]

Check for any loose pieces from the parking brake.

 

[volver]

I have the same problem. A low frequency grinding from the rear end when accelerating and turning at the same time.

I did some investigation: pinion is leaking badly, oil level is fine but never added any friction modifier after refilling. The noise sounds like it is comming from the rear end but i feel a rumbeling from under my feet as if it were the transfer case.

 

[robertoa1a]

I don't have a x-fer case but yeah. It feels like clutch slipping then catching or like the rear is hitting small bumps. Thats why I suspected a limited slip issue. Does anyone know how many mechanic hours are involved in a diferential rebuild? I think I saw something in hotrod magazine but I'll be lucky to find that again.

 

[robertoa1a]

I'm going to find an empty parking lot and drive around in circles so I can discribe the problem better. It should lock and squeel a little. I hope I don't get a ticket. Does any one what fluid too add to a rear w/ posi?

 

[robertoa1a]

Okay went out today to check out this problem and discovered that IT ALSO DOES THIS IN PARK. It turns out that the power steering pump is bogging down the engine and making it shake. I took my Explorer out on a date. A coctail of sea foam in the brake booster line, and a PCV. A cheep date!

I noticed a little improvement. I think the power steering pump may be on the spritz.

 

[Cobraguy]

A diff rebuild depends on the depth of repair needed. Just seals and all new bearings isn't too bad because you rarely have to adjust the pinion depth or back lash. Just reuse the factory shims. But if you need to replace the ring and pinion, then it's obviously more money because now you need to set the gears up. Now, if I am setting up a set of factory gears, it is usually a whole bunch easier than setting up aftermarket gears. They just seem to fit better using the pinion depth of the original pinion. But aftermarket gears are a whole different animal. I've actually sent gear sets back because you just couldn't get a decent pattern on them. However, the good aftermarket gear sets come stamped with the pinion depth right on them...so all you need is your pinion depth gauge to calculate the exact shim you need. I never charge more labor for freshening the posi as I believe disassembly and inspection is part of the job anyway. Axle seals and bearings are more yet depending on the style of bearing and how it is installed. So as you can see, it can really vary. I would say anywhere between 2.5 and 5.0 hours. If the cross shaft lock pin is broken, add straight time to remove it.

I have pinion bearings for most popular rear diffs that have been honed to where it will slip on and off the pinion. That way I can save a ton of time changing shims for the pinion depth. You could do the same if you wanted to try this yourself. But if you aren't familiar with setting up a differential, have someone there who is to help guide you through it the first couple of times.

 

[robertoa1a]

Thanks cobra. That pretty much covers every thing I needed to know. I like to catch theese kinds of things early so I don't have to replace every thing. Is some minor leakage normal after 130,000 miles? Dry evidence of lube w/no drips.