I have an 03 EXPY, 5.4 2wd. I hear a mid tone whine that seems to come from the rear end around 50-60 mph...

If I let off the gas it seems to lessen, back on the gas and it's there again...

Anyone know if this is a known issue?

Thanks
Patrick

 

My wife's 03 2wd 5.4 had the same problem. They regeared the rear end and that helped for about 5000 miles. I just got it back the other day after another week in the shop and they put another driveshaft in that is suppossed to fix it again. We'll see.

 

My wife's 03 XLT was doing the same thing. It was pretty bad from 40 to 60 mph. The dealership replaced the ring and pinion under warranty. It is now silent. We'll see how long this lasts.

 

I am no expert on this subject but have read both here and elsewhere that first year IRS Expeditions/Navigators/Aviators were likely to have problems with rear end whine. I seem to remember it got "fixed" early in the 04 model year. I know I reported about a year ago my experience with a loaner Aviator that had a horrible whine just as you describe, had about 10k miles and was from my dealers used car lot.

Try doing a search here on this forum and maybe on rear ends or whatever it would be called. I do believe a fix is out there for this problem.

My 05 Navigator only has 500 miles so far so and I have not experienced that particular problem. Just getting my shins barked by the auto running boards when I am helping her load stuff in the rear door and forget when she opens the front door first. Ouch.
Bill

 

Took a tech for a ride this am in my '03 5.4 4wd to hear the whine, and he immediately picked it out as the rear end pinion. He wasn't too happy about doing 60 in the snow, but as long as he is fixing it. Now we'll see if he can get that and the trans service done today.

 

The whine isn't fixed yet, they ordered a new rear diff. 1 week delivery. Trans service done, although $200 was a shocker.