Whine in rear end @ high speeds

[computertech]

Changed the rear diff fluid and added the motorcraft additive, drove it for a few miles and its unnoticable now,sounds great, thanks you guys !

[arejayesss]

I have experienced the same thing since I got mine last year in June. I have never worried about it too much. It may be something to be concerned about though, I'm not sure.

[greggash]

there is a TSB for axles

they go at about that milage, mine did

also you may wish to change the rear axle fluid every 30K

so you dont toast the diff


etc etc

have it looked at, pull the axles look for gauling

[magindat]

The axle set for the TSB was like $250.
I did mine (had to) when I did my 4.10 gears. Saved me a bunch of labor, though.
If you can, put a drainable dif cover on. I have the Moser.
Fill her with Redline diff oil - quietest I've found.

[BUCKWHEAT]

If you have aftermarket gears, they sometimes whine as you described. Have someone check the gear set up & clearances.

If your gears are OEM 3:55's, consider going to the Ford Motorsport 4:10's when you change your axles. Have a reputable shop set them up & they won't whine.

Good luck

[Bluerauder]

I come to find @ 50-75mph while on the pedal i hear a high pitched noise comming from the rear like a "hoooooooooooooooo" only when on the gas...When I take my foot off it stops and immediatly returns when back to gas pedal.
More discussion here on improper bashlash and/or pinion depth as a possible cause for gear whine .... >>> http://www.mercurymarauder.net/forums/showthread.php?t=34399&highlight=rear+end+whine

[JimmyXR7]

there is a TSB for axles

they go at about that milage, mine did

also you may wish to change the rear axle fluid every 30K

so you dont toast the diff


etc etc

have it looked at, pull the axles look for gauling

Good advice. If stock gears, pull the differential cover and look through the oil in the catch pan for metal. Use a magnet if uncertain. If no metal, then refill and make sure you use limited slip gear oil.
Jim
PS the posi-traction clutches add more particles to the gear oil, so early gear oil changes make sense. I changed mine at 45K and the oil had lost the honey color and was dirty brown.

[arejayesss]

Actually, according to Brians report, that issue was taken care of by previous owner. This is a different whine (at least for me) that only is present between like 50 - 75 or so. It only happens when your foot is on the go pedal, and stops right when you release it.

Hey Greg!!! Haven't talked to you in a while. Good to see you, well not 'see' but you know what I mean

Ryan

[RF Overlord]

computertech, welcome to the site...

Sounds like a backlash issue...if no one's touched the diff then have a competent tech check for the axle TSB if the car was made before 11/2002....

[CRUZTAKER]

...it's your axles...

I wouldn't go as far as to give such a definitive answer to a new guy if you really cannot diagnose it in person.

There are a number of things that cause 'whine' in the rear at various speeds.

Mine has a definate whine between 37-45 mph. It has now for nearly four years. It started 10 minutes after installing my gears. My axles are fine.
It doesn't hurt anything. The installer just wasn't as precise as he could have been.

I put headers on shortly there after to cover the sound.:D

[Vortech347]

If its a 300A you'll want to do the Axle TSB, considering what you get it really isn't that expensive and its pretty easy to do it yourself. My axles were trashed.

[Glenn]

Axle bearings - bet on it!!!!!!!! I had the same noise. It will only get worse.

Glenn

[CRUZTAKER]

Must be a southern thing....all the southerners are determined to believe it's axle related.

The notherners all say gear related.

So who's goin' chicken huntin'?

It's on you now computertech.