I recently posted a thread about lots of grease all over back left brake area.. Possibilities were either the O-ring or inner seal, or the bearing.

Now when I was just driving about 45 mph on a long left curve I noticed a constant siren sounding whirl like you would here from a Nuclear power plant siren. It's only when I'm making left turns around that speed. And it's the left rear brake area with all the grease on it..

Is that the rear bearing screaming at me??
Thanks and I will record it and post it here soon as well..

 

That's pretty loud.

 

My guess based on a service order within our package of receipts prior to our purchase would be the differential. We too noticed the grease in the rear wheel well prior to our purchase and noticed the differential have been replaced a few weeks prior to our purchase. We had the o-ring soon replaced after our purchase.

2003 Discovery with high miles services complete - 134K

 

My bet is rear wheel bearing.
Makes a horrible grinding.

 

If it turns out not to be a wheel bearing...
FYI I had a loud squeal coming from my rear end...loud! Indy mechanic opened the rear differential to find the "roll Pin" had loosened and was jamming into something...the diff lock ring I think? Been a couple years since the repair so can't remember exactly what the terminology was. (said it was not the first one he saw)
I remember there was some definite signs of damage one the the diff was opened up.
I replaced the rear differential with a rebuilt one and perfect since.
Something else to think about
Good luck

 

rear hub?

 

The noise/whirling would only make the noise while in a left turning curve... so thats what made me think pressure on the bearing/hub on the rear left where the grease is.. I will pull the hub and check it out

 

Don't pull the hub to check it out, jack the rear tire off the ground and wiggle the tire while holding it at the top and bottom. If there is movement the bearings are for sure gone.

 

I lifted the tire in the air and there is absolutely no movement or play.
could that whirling be coming from the rear differential? it doesn't make that sound all the time and I only seem to hear it around 35 to 40 miles per hour range

 

Pop the fill plug and make sure there's plenty of oil in it?

Dave