Diff Lube Change Question

[lsmit541]

I'm planning on swapping out the rear end lube soon on my 07 GT and was wondering if anyone has had experience using the Lucas synthetic 75w140 without the friction modifier. It appears that a lot of folks have and haven't had any cornering chatter problems from what I've read and Lucas maintains that no additive is necessary. I would rather hear the opinions of you guys on this. Thanks.