I decided to purchase the Redline 75w-90. I've always liked their oil so I figured the gear lube should be of high quality.
I do have a question for those that know Crown Vics/Grand Marquis with the traction-lock transmission. The gear lube says it comes with the friction modifier in the formulation but that some MAY need to be added if any chatter is heard. I ordered some of their modifier product just in case. I'm having a shop do the differential cover removal and fluid replacement and I will be giving them the fluid to fill it with. My question is this...should I have them add ANY of the friction modifier or should I just go with the bottle formulation and wait to hear any chatter? I really don't want to take the vehicle back to add anything but I don't want too much modifier in the differential either as this may cause the LSD to malfunction. Is it just a simple filler hole on the housing top? (Due to a bad back I find it difficult to look under the car at this point).
Thanks for any help you folks can give me.
I do have a question for those that know Crown Vics/Grand Marquis with the traction-lock transmission. The gear lube says it comes with the friction modifier in the formulation but that some MAY need to be added if any chatter is heard. I ordered some of their modifier product just in case. I'm having a shop do the differential cover removal and fluid replacement and I will be giving them the fluid to fill it with. My question is this...should I have them add ANY of the friction modifier or should I just go with the bottle formulation and wait to hear any chatter? I really don't want to take the vehicle back to add anything but I don't want too much modifier in the differential either as this may cause the LSD to malfunction. Is it just a simple filler hole on the housing top? (Due to a bad back I find it difficult to look under the car at this point).
Thanks for any help you folks can give me.
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