2003 Suzuki LT-Z400 Factory Service Manual, Page 121Get this manual
COOLING AND LUBRICATION SYSTEM
At the time of the system is filled with 50:50 mixture of water and ethylene glycol anti-freezeThis 50:50 mixture will provide the optimum corrosion protection and and will protect the cooling system at above -31 (24F)is to be exposed to temperatures below -31 "C ratio should be increased up to 55Yo or 60 to the
ethylene waterDo not mix an alcohol and different or less than
20 40 60 80 1GO