This is a 2003 f150 xltfx4 super crew cab 4X4 5.4 liter and the vehicle has developed an excessive high frequency wine sound from the rearend. The rearend has been replaced by the dealer 2 monthes ago and now this noise has returned. Is there an idea of what this is and what is the fix? Is something somewhere else causing this noise to appear in the rear? Please advise.

 

Give a little more info. Does the sound stop when you let off the gas at what speed does it start. You could have a case of Fords dreaded no fix rear end whine.

 

The noise does go away when you let off the gas. The sound occures at 5mph and above. He has had the rear end replaced once and after installation of the new one the noise reapeared again after about 2 monthes. The dealer contacted Ford and they just explained about some BS exceptable noise levels. What do you think?

 

Here's an expert opinion on rear end noise.
Scroll down to General Information - Diagnosing Noise.
www.ring-pinion.com/tech/techind.html

 

I think it's a bunch of crap that Ford won't come up with a fix for this problem. There are alot of newer trucks out there with this problem. Mine is a 2002 F-150 5.4, 3.55 Limited slip axle that whines at anything over 35 mph but really starts to howl over 55 mph.Take my foot of the gas and it goes away. Dealer has replaced the bearings and ring and pinion but no help. Some people have gotten the whole axle replaced and the noise is gone for good. I use my truck for work as well as pleasure and I can't afford to keep taking it back to the dealer while they play " lets keep changing parts till we figure it out" Iv'e had it there on three seperate occasions two days at a time and it costs me big bucks because I can't work while it's in the shop. If you find out a fix please let me know. Other than this problem I love my truck. Good Luck!

 

My 2000 9.75" had a whine. Ford looked at it twice with no resolution. The gear pattern/pinion depth was incorrect from the factory and after they pretended to fix it, or rubbed their nubs, or whatever they did. They were total Dilberts. I finally got sick of them and set my rear end up myself with a new ring and pinion (this was DURING the warranty). It never made noise again. My new Lightning 9.75" is perfectly quiet....Thank God !

 

Back in Feb I bought a 2003 fx4 reg cab. About 300 miles into the ownership, I developed a whine in my rear. I got fed up and put my truck up on jacks, choked both tires,cranked it up and put it in drive. (DO NOT RECOMEND) Then I crawled under to figure out what the noise was. It was my rear drive shaft at the front "U" joint. It would do it from 5mph all the way up. I took it to a Lincoln dealer.(I bought it out of state) He ordered and replaced my rear drive shaft and no more noise. He said that some bolt or pin had come loose and worn out. Maybe this helps.