Vehicle engine hand tools fit into confined areas in the engine assembly for maintenance and repair activities. Cylinder gland nut wrenches fit hydraulic cylinders on vehicles featuring large gland nuts. E-Clips fit into grooves cut into shafts and hose fittings to secure connections in cooling system assemblies. Engine barring sockets lock onto a vehicle's engine and help manually rotate it for easing injector work and valve lash adjustments. Lock ring spanner wrenches fit into a slot on the locking ring and provide leverage for tightening or loosening the lock nut. STC release tools disconnect Snap-to-Connect hose fittings.