[svxistentialist]

Petr

As Earthworm says, this knocking on turning usually means bad axles. Specifically the CV joint on the outside of the axle.

If there is wear in these CV joints, particularly bad wear, it is possible to check this by grabbing the axle [we call then "half shafts" here] firmly and pulling it in or out along its axis. If the joint is damaged, there will be noticable play, otherwise all will be tight.

I'm willing to bet you may have a bad bushing on the lower chassis subframe, that is causing a knock when torque is applied with the wheels locked over. This torque would generally not be as severe when moving, as the gradual turn-in will cause all the sub-frame isolating mounts to take up median positions. That is to say there will be torque, but not enough to shift the subframe over enough to knock, while moving.

The same logic could also be applied to an engine or gearbox stabilizer mounting. If cracked, broken or worn, one of these could allow metal to metal contact.

Jacking the engine up from underneath might well show you subframe or mounting isolator movement that should not be there.

Worth a look.

Joe