co-driver
Tuning reference /differential

Differential (Accel & Decel)

Controls how much the driven wheels lock together — at acceleration and on engine braking.

Your dataCar #3650· last 3 laps
Rear L slip ratio (throttle > 0.5)25.9%
Rear R slip ratio (throttle > 0.5)25.7%
Rear L−R Δ0.12%

What it does

Forza's diff is a clutch-pack LSD with two values: Acceleration % and Deceleration %. Both are "how much the diff locks" — 0% is fully open (each wheel free to spin independently), 100% is locked (both driven wheels turning together regardless of grip).

Higher accel % = more traction off corners (good for power-down), but the locked wheels resist rotation, so the car understeers more on throttle exit. Lower accel = the inside wheel can spin freely, the car rotates more on throttle but may dribble power.

Higher decel % = stable corner entry (engine braking pushed evenly to both wheels), but reduces rotation on lift-off. Lower decel = the rear can swing on lift, useful for RWD trail-braking.

For FWD cars, the LSD on the front works the same way — but stiffening accel adds torque-steer.

In-game controls

Acceleration (driven axle)
Range: FH6 RWD: 40–60%. AWD: 50–70%. Drag: 80–100%. Drift: 100%. FWD road: 20–40%. (FH6 narrowed the useful band — defaults sit lower than in FH5.)
Raise →
more traction out of corners, more on-power understeer
← Lower
more rotation on throttle, risk of inside-wheel spin
Deceleration (driven axle)
Range: FH6 RWD/AWD: 20–40%; higher for rally
Raise →
stable on entry, less rotation on lift
← Lower
more rotation on lift-off, useful for trail-braking, can feel nervous

Watch these telemetry signals

  • Tire slip ratio (longitudinal)slipRatio
    Where: Corner panels, "slip R" — front/rear and L/R
    Compare driven-axle L vs R under power. Big asymmetry (one wheel spinning, the other gripping) = diff too open → raise accel. Both spinning equally = diff working, look at tires/aero.
  • Throttle inputthrottle
    Where: Trace strip, green line
    Cross-reference throttle trace with slip-ratio spikes — if every throttle stab causes wheelspin, the issue is diff (or tire pressure) not driver
  • Tire slip angle (lateral)slipAngle
    Where: Corner panels, "slip A" — compare front vs rear
    On lift-off into a corner: rear slip-angle spike for RWD = low decel %, may want more if you want stability. Drifters keep it low on purpose.

Symptom → fix

What you feel Likely cause Try this
One rear wheel lights up under power, other doesn'tDiff too open under accelerationRaise accel % by 10 at a time until both wheels share slip
Car pushes wide on throttle out of slow cornersAccel % too high — diff locking and resisting rotationLower accel by 5–10
Snap oversteer on lift-off (RWD)Decel % too low — rear unhooks when engine dragsRaise decel 5–10
AWD car turns in, then pushes the moment you touch gasHigh accel combined with rear-biased center diff fighting itselfDrop accel a step; consider shifting center diff slightly forward

Symptoms that point here

Related

Center Differential (AWD)Alignment (Camber, Caster, Toe)Tire Pressure