Differential oils are used to alter the handling of the car, the steering, acceleration, and overall feel of the car. For a better understanding, please read Please check THEGuide HERE . For some quick advice, read below:
Front:
Most common oils used: 5000 – 10 000, basic set up 5000.
Thinner: Increases off-power corner entry steering. Reduces steering and pull out of a corner. If oil is too thin corner entry steering may be too aggressive, not enough steering out of the corner, as well as acceleration.
Thicker: Smoother (less) corner entry steering. More steering and pull out of corners.
Center:
Most common oils used: 3000 – 10 000, basic setup 5000.
Thinner: Front wheels unload and balloon more during acceleration, which leads to less aggressive acceleration. Decreases on-power steering. Easier to drive on slippery and bumpy tracks.
Thicker: Increased 4WD drive effect. Improved acceleration. Increased on-power steering. Harder to drive on slippery and bumpy tracks.
Rear:
Most common oils used: 1000-5000, basic setup 3000.
Thinner: Easier to drive on power Increased corner entry steering. Too thin oil can make the rear end loose traction suddenly, specially on corner entry.
Thicker: Smoother and easier to drive entering corners, rear traction more consistent. Less corner entry steering. Harder to drive on power, specially on slippery or bumpy tracks.