2005 Navigator. Differential issues or what else?

[4rickyg]

2005 Navigator series 60. 150,000 miles. I started to hear a pulsating whining sound when I step on the accelerator. Pulled over to see what was going on and heard a Thump Thump Thump like a rotating motion. Got to a safe place to crawl under and look at U-joints they look fine. At slow speed evaluation I heard some cracking and popping sound like from the differential or axles. No leaking SEALS or anything like that. Did not feel extremely hot.

Had it towed to ww Williams in Montgomery Alabama waiting in their parking lot now. Hopefully they will look at it first thing in the morning. When they pulled the axle oil came out smelled kind of burnt! I don't have a good feeling about this one..

[Rodger]

Hope this turns out ok for you.  As far as burnt smell, diff's always smell like burnt oily smell to me so hopefully that's not a indicator of something bad.

[AndyinMelbourne]

Were you able to rotate the driveshaft at all?  Is there any play in the U-joints?  I'd suspect the U-joints as well.

 

[4rickyg]

Just a little bit of play in the drive shaft maybe 1/8"

[96 EVO]

Anything on the magnet drain plug?

[jacwjames]

When was the last time the chassis was lubed, did they/you do the driveshafts?  When was the last time the oil level in the diff checked?

[4rickyg]

Have not drained it yet. Drive shaft and Chassis has been lubed yearly. I don't think the diff fluid has ever been changed since I've owned it. Not very proud to say that..

[96 EVO]

It last's a long time, but, if factory fill, it's due.

[4rickyg]

Lol, yeah 19 years is a long time..  I have owned it 7 years. 

[Ivan K]

Burnt is not a usual smell of differential oil IMO but it does smell funny, nasty really. If it is REALLY burnt, most likely a bearing failed. That by itself would not be a big deal if it did not yet weld itself and rotated the race inside the hub or on the spindle. Worst case pinion bearing but that one gets plenty of lubrication. They should know pretty quick. Jacking up and rotating the wheels would/should give a hint with the shaft or axle already removed. Joint is a possibility but would not burn oil. Broken gear or spider would not burn it either.

[4rickyg]

At highway speed it really didn't sound that bad just a hum. But at Slow speed idle just a roll sounded really terrible. Was more of a popping sound like something was getting stuck.

[Jdw12345]

Maybe a ABS sensor hitting the tone ring….

 If you can be at the shop when they drain the lube, you can verify what you’re being told. Possibly even witness the drain plug being removed, unfortunately I don’t trust anyone to perform work on my coach. 
 The drain plug should have a magnet in it. 

Edited 19 hours ago by Jdw12345

[frankogrly]

Had a similar problem a few years ago. The opinion was a pinion gear problem. I had a shop drain some of the fluid and replace it with BG additive. After about 500 miles it quieted down. That was a few thousand miles ago and all is still good.

Frank O

01 Endeavor

165,000 miles

[Mark C]

I had a whining noise when coasting that went away when on the accelerator.  When I arrived at my destination and put the transmission in reverse to back into my spot, the gears in the rear end broke into pieces and I was stuck where I sat.  $5,300 later I had a rebuilt rear end.  I had about 110,000 miles at the time on a 2009 Monaco Dynasty.