For vehicles with diesel engines and wet flywheels, if frequently driven at low speed (at lower revs than idle), the fuel injection control lever etc. of the fuel injection pump can prematurely wear, and this will cause the injection amount to decrease when the engine revs are low. If frequently driven at low speed in such a state, the engine revs will drop and the flywheel can resonate, and at worst the inside of the flywheel could be damage, in which case the vehicle could stall.
