1955 chevy PU [..in good condition] I would like to use auto rx for my manual transmission & differential. I have synthetic fluids in the units now. Is it OK to to put in the Auto Rx? Will I realize the full benefits if I'm using synthetics? Thank you,
I see no problem running the cleaning dose in your current fill of lube in the transmission and differential. The normal application would be for adding at a rate of 1 fluid ounce per quart capacity. Then operate for 1000 miles prior to changing out the lubricant.
The only performance factor that would in jeopardy is if you where running ARX to help with a tail stock seal leak or end bearing seals on the differential. I would highly recommend switching over to a mineral oil based trans lube or gear oil for that.
