Fastrax Shock And Diff Oil for RC Cars & Trucks

Dial in your suspension and driveline with our Shock And Diff Oil range. We stock graded silicone oils from Hudy, Associated, Core RC, Losi and Fastrax, with clear cSt and WT markings for easy tuning.

Shock oil: lighter viscosities (around 200-450 cSt) give faster response and more grip on low-bite tracks; heavier (500-1000+ cSt) slow the chassis, reduce roll and help on high-grip or big-jump layouts. Always match left/right and bleed air from the shocks for consistent pack.

Diff oil: gear diffs use silicone from 1,000 cSt to 1,000,000 cSt. Heavier front can calm turn-in and add on-power stability; heavier centre sends more drive rearward for punch; heavier rear can increase forward bite but may reduce rotation. Crawlers and bashers often prefer very heavy centre/rear; racers tune by temperature and surface.

Need a specific weight? Use the filters to find your oil, or ask our friendly, knowledgeable team for advice. We carry large stocks for fast dispatch, with UK next day delivery available.