I have a 2003 F-150 FX4 SuperCab and a couple days ago I was turning into a parking space and noticed a huge vibration in the rear of the truck. It doesn't matter which way I turn. I have an appointment with the dealer next Tuesday and it should be covered under warranty but wanted to get your guys input as to what this could be. THe truck has 44K miles on it and I purchased the extended warranty. I am sure this could be a million different things.

 

It probably needs friction modifier added to the rearend, if it is limited slip. Mine did. Hope this helps.........

 

drain the rear axle, put in new synthetic 75-90 gear lube and definitly add the 6 ounces of anti slip addative. the chatter is normal for gear lube without the addative.

 

Thanks guys.. Like I said I am taking it to the dealer because that is what I paid for the extended warranty but I just wanted to be prepared because you know how some dealers are. Mine has been great but every now and then you get someone having a bad day. Thanks again..