Shock oil is something we get asked about regularly so we thought it would be a good idea to give you some information to give you a starting point to help you choose a suitable oil for your vehicle. The manual doesn’t always have information on oil properties and there are many things to consider when choosing shock oils. Shock oil weight is only one variable used in suspension tuning spring rates, tyres, foams, gearing all make a difference to the way the car responds. How you tune your car is a completely individual decision based on driving style, terrain and your own personal preference. It is very difficult for us to recommend the perfect shock oil because no two people have the same setup or driving requirements. For a new car the best place to start is with the manufacturers build recommendations then tune from there. 

Shock oil is rated by WT or CST and the higher the number the thicker the oil. WT and CST are not directly comparable but below is a rough guide comparing the two

10wt = 100cst
15wt = 150cst
20wt = 200cst
25wt = 275cst
30wt = 350cst
35wt = 425cst
40wt = 500cst
45wt = 575cst
50wt = 650cst
55wt = 725cst
60wt = 800cst
70wt = 900cst
80wt = 1000cst

This is a basic guide to help you select the correct oil. The rear damping will be softer by default a lower WT.

1:10 Scale Buggy 4WD
Front: 30–35wt
Thinner oil is used when driving on low traction tracks. If more accuracy is required change to a thicker oil. 
Rear: 30 - 35wt
Low-traction surfaces and soft damping improves grip, but there’s a risk of the rear becoming twitchy if this happens increase damping in the rear

1:10 Scale Road cars
Road Cars use thinner Oil and it is usually the same in the front and rear. Thinner oil will give you a better grip but turning will be slower and the vehicle will roll more in the turns The most common oils for road cars are 30wt–40wt. Road cars tend to have shorter spring travel so there is less space for damping. Careful set up is required as road cars are alot more sensitive to adjustment.

1:10 Scale Buggy or Short Course 2WD
Front: 25 - 30wt
Thicker oil will provide better traction and makes steering faster and more accurate
Thinner oil will improve grip on a slippery but steering will be more sluggish

Rear: 25 - 30wt
Thinner oil will provide better grip in the rear. The result is the same as in the front – thinner oil improves the grip but the rear of the car will be more twitchy when using thin oils. The damping should be enough to not let the rear bounce. If it does change to a thicker oil. In general, the rear is adjusted to have softer damping for better grip.

1:10 Scale Short Course 4WD
Front: 30 - 35wt
For slippery tracks use 30wt
high-traction tracks, 35wt

Rear: 30wt - 35wt
To improve grip on the rear, use a thinner oil and if driving on high traction tracks use a thicker oil.

The newer short-course cars can run on thinner oils that provide sufficient damping. See, however, that the car doesn’t dive at bumps or when landing. If the rear starts to bounce, you may have to improve the damping.

1:8 Scale Buggies and Truggies
Front: 35wt – 45wt
Depending on the bumps and jumps at the track, thinner oils can be used in the front if better grip is desired. Landing after jumps and bumps require good damping, so you might have to choose stiffer damping at the expense of grip.

Rear: 30wt – 40wt
Soft damping improves grip but the risk involved is that the rear might start to bounce and the car might dive when landing. Generally the damping should be softer in the rear than the front.

1:8 vehicles category are heavier than 1:10 and it is important to have the right amount of damping. With heavier cars there is more chance of diving at bumps and when landing after jumps. If the damping is too stiff in the front it will result in under steer and if the damping is too soft the front will dive when braking. If you set the rear to softer damping you will get better grip when turning but make sure there is enough damping for landings.