The shop that installed the Auburn Pro Series posi put Royal Purple syn. in the rearened. Now a 1k miles later it is starting to chatter on tight turns. I only drove like this for two days. My guestion is, do you think I did any damage to the unit. I went out and picked up some conventional gear lube and a bottle of additive. Do you think it will be all right if I change the fluid?

 

Auborn recommends 80w90 dino gear oil .....NO synth....

I made that mistake after 300 miles..Changed to Dino and no problems in 4years....

When you pull of the diff cover check for metal....

 

not sure if they rec it or not....but did you put in any friction modifier?

 

After asking the shop why they used the Royal purple they said something along the lines of, we use it on all posi units except such and such. I then told them I was on the Auburn web site and found out that they recommend dyno gear lube. Was news to them.
Like I said it only chattered a little before I stopped driving it. So I'll put the Lucas in with the additive. Thanks for telling me yours was all right after you switched. Rick