Vibration while turning

[midex717]

Gents,

I own a '97 Ford Expedition with around 108k miles on her. Recently it has developed a vibration while turning left, or right, and it only occurs when power is being applied in the turn. It does not occur in a coasting turn. It really feels like the vibration is up front, but could be in the rear also. I dug around online, and found that it could be the clutch packs in the rear differential "chattering".

Is this a major issue, or a major fix? One fix I read about is to change the differential lube, and add a friction modifier to the differential. Will that work?

I really appreciate any responses, or suggestions on a fix. My daughter has the truck at school for the winter, and hope it doesn't cause any problems for her.

Thanks!!!

[Jeremy airjer W]

I a deserted parking lot with plenty of space make the tightest runs you can. Keep going in circles for at least 2 complete revolutions. If you hear a grinding noise its the clutches in the rear limited slip.

[midex717]

Thanks for the reply airjer!

I'll try your suggestion of driving in circles! Ha!

If the problem is the clutches in the differential, is it a high cost fix, or will changing the gear lube, and adding an extra lubricant help?

[Scott K]

Changing the fluid and adding the friction modifier has worked in the past, and would be an easier/cheaper fix. But if it doesnt work, you are then out the cost of changing the fluid! If it is the clutches chattering, it wont hurt anything to let it chatter, it will just cause the diff clutches to wear faster, and the limited rear diff wont work as well.