vibration when turning

[Sam Worrell]

I have a 2004 Sport trac. Recently I have noticed that when I make a right or left turn I get a slight vibration from the rear end (or at least it feels it's coming from the rear end) I have tested on several occasion. When I am at a stand still and I take off going strait I get no vibration what's so ever but, when I make the slightest turn left or right I get a vibration and you can clearly feel it. Now, it does not matter how slow or how hard I take off it will still vibrate, then once I get my front wheels strait again it goes away. It only happens when the vehicle is turning, it never vibrates when I am going strait taking off. has anyone heard of this? or know what I might be? Thanks for any feedback.

 

[EddieS'04]

Sam, if you have the limited slip rear end. You might need to add a bottle of ford friction modifier. Or the clutches in the limited slip are failing.

 

[Sam Worrell]

I'm assuming the number on the rear end will tell me if it's a limited slip or not? The friction modifier is just as simple as adding diferential fluid correct? thank you

 

[EddieS'04]

look on the drivers door jam.



Code Axle 46 — 3.73 non-limited slip 42 — 4.10 non-limited slip D4 — 3.73 limited slip D2 — 4.10 limited slip



Adding the friction modifier is the same as fluid fill point. It is a 4oz bottle about $8 from ford.

 

[Sam Worrell]

Thanks Fast Eddie 04

 

[EddieS'04]

Your welcome..

If you do have the limited slip and you add the modifier. Find an open parking lot where you can do some figure 8's at slow speed, for a couple of minutes. That will open and close the clutches and work the modifier into them faster.

 

[Sam Worrell]

will do thanks again

 

[Bill Barber]

FE may be right if you have an LS diff, the most common symptom of the 8.8 LS diff is they make noise.

When the truck is at full temp from actually driving it, do some very low speed lock to lock turns, if you hear a groaning noise and you do have LS it is the clutches.

Fric mod is a temp fix, give it a try, can't hurt.

 

[Jeremy Dincher]

Sam, what solution finally worked out for you. I am new to the forum and i found that you are having the same problem. Only when turning and never when taking off in a straight line, if you could please post your fix i would greatly appreciate it. thank you

 

[Bill Ellis]

I had that issue at about 30K miles on my '04. Dealer replaced clutch pack under warranty. No more problems now with 74,5xx miles on the Trac.