Most Hobby stores that sell high end RC cars & parts have silicone oil, no additives, in different weights for their RC Shocks, I have several bottles of different weights... There is an RC store at the north west corner of 35th Ave & Cactus and another at 35th Ave just north of Glendale Ave on the west side... One might google Factory Team Shock Fluid or just RC Shock Fluid much info there...