Physics Gearbox shaking, rpm stutter?


ive have a important question,

in some modded cars, i have a shaking (no matter if TC is on or off) when i accelerate, it feels like the rev bounces between some little rpm's and it go's higher or farther the more rpm and mph the engine/car has.
The rpm's dont go like wrooooooooooom mor like woorirroiriruooom

I don't know, to describe it really good, i would say it is like the rpm is shaking a little bit in the moment i accelerate, you can hear it "in TV and in Cockpit" the tacho needle is also bouncing forth and back.

I think it has something to do with drivetrain.ini

that the sound also stutter or shake a little bit.
Last edited:


Southern Ontario
Sounds like the effects of autoclutch in some form, either way too wide shifting range or your controls have it enabled & the dev never tested it with that feature enabled.
Here is the drivetrain.ini from one of these "shaking cars"

TYPE=RWD ; Wheel drive. Possible options: FWD (Front Wheel Drive), RWD (Rear Wheel Drive)

COUNT=5 ; forward gears number
GEAR_R=-3.16 ; rear gear ratio
; forward gears ratios. must be equal to number of gears defined on count

FINAL=3.02 ; final gear ratio

POWER=0.30 ; differential lock under power. 1.0=100% lock - 0 0% lock
COAST=0.40 ; differential lock under coasting. 1.0=100% lock 0=0% lock
PRELOAD=5 ; preload torque setting

CHANGE_UP_TIME=100 ; change up time in milliseconds
CHANGE_DN_TIME=300 ; change down time in milliseconds
AUTO_CUTOFF_TIME=60 ; Auto cutoff time for upshifts in milliseconds, 0 to disable
SUPPORTS_SHIFTER=0 ; 1=Car supports shifter, 0=car supports only paddles
VALID_SHIFT_RPM_WINDOW=800 ;range window additional to the precise rev matching rpm that permits gear engage.
CONTROLS_WINDOW_GAIN=0.4 ;multiplayer for gas,brake,clutch pedals that permits gear engage on different rev matching rpm. the lower the more difficult.
INERTIA=0.016 ; gearbox inertia. default values to 0.02 if not set


UPSHIFT_PROFILE=NONE ; Name of the autoclutch profile for upshifts. NONE to disable autoclutch on shift up
DOWNSHIFT_PROFILE=DOWNSHIFT_PROFILE ; Same as above for downshifts
USE_ON_CHANGES=1 ; Use the autoclutch on gear shifts even when autoclutch is set to off. Needed for cars with semiautomatic gearboxes. values 1,0
MIN_RPM=1200 ; Minimum rpm for autoclutch engadgement
MAX_RPM=1800 ; Maximum rpm for autoclutch engadgement

POINT_0=20 ; Time to reach fully depress clutch
POINT_1=60 ; Time to start releasing clutch
POINT_2=120 ; Time to reach fully released clutch

ELECTRONIC=1 ; If =1 then it is a feature of the car and cannot be disabled
POINT_0=30 ; Time to reach full level
POINT_1=120 ; Time to start releasing gas
POINT_2=200 ; Time to reach 0 gas
LEVEL=0.4 ; Gas level to be reached

I changed the drivetrain.ini = nothing
i disabled auto clutch and intermediate gas clutch= nothing

Newes Test, changed drivetrain.ini from Pagani and it go's away