So, as I stated in an earlier thread, I decided to change my differential fluid last Friday while I was changing my transmission fluid. Being the Viper noob that I am, I thought all I had to do was fill the diff back up with my Pennzoil 75W-140 and call it a day just like all of the other cars I've owned. Um, nope.
I was driving the car yesterday and at slow speeds with the wheel at or near lock, I could hear a terrible grinding/groaning sound coming from the car, which I could actually feel. After a little research, I realized that I should have added the friction modifier (4oz bottle) to the diff fluid when I made the change. So, I went to Napa, bought a $10.00 bottle, jacked the car back up last night (arrrggggg), used my wife's measuring cup from the kitchen to meter out 4oz of diff fluid (she didn't seem to like that) and added the modifier.
Much to my amazement, the sound is completely gone!!!!! So, for any noobs like me who are going to change out your diff fluid, if the fluid you are putting in doesn't already have the friction modifier in it, it is an absolute must. You really won't like the sound you hear from your diff if you don't.