Me '05 E350 w/ 120,000 miles has developed a rear end whine/growl. It's most noticeable at about 45mph and happens both under power and coasting until about 50 mph, above that it seems to only happen under load, not so much coasting.

I'm thinking it's the ring/pinion.

Can anyone tell me what the book rate labor hours are for a rebuild - including the ring, pinion, bearings and limited slip clutches (is there anything else)?

I've heard that my local Ford dealer doesn't do rebuilds and will want to sell me a new rear end - what would that cost?

Any guesses as to how long can I run it this way? Changing the gear lube didn't help.

 

Generally a whining noise from the rear end is a outer bearing gone bad.

Not a major re-build.

If you can, jack up the rear end, on jack stands, block the front wheels, and with a helper in the seat, start the van, put in gear, and run the wheels, you'll hear which side has the bad bearing.

 

Hey people pay quite a bit of money to get that sound by switching to spur gears.

 

Do what wildman25 says, but first go to Harbor Freight and get a cheap automotive stethoscope, a great tool for locating bad bearings. Use the solid probe, hold it against the housing at various points. Bad bearings usually rumble, not whine, however.