Check the lift chains carefully for damage, breaks or pins sticking out on on side. If damage is spotted, remove the key to prevent anyone using the truck and report it immediately.
Here is a chain that was removed from a working forklift in South West Wales in September 2011. At least ten links were damaged as shown here. When removed, it was almost impossible to flex the chain because of rust! This forklift was the one designated for me to train people on!