Dear Pakwheels fellows,
I have purchased a suzuki cultus 2003 (ODO 170K) a couple of months back and is well maintained. The previous owner was using Caltex Havoline 20W50 oil and car is running without thermostat valve with automatic fan. it was kept for 6 years with the previous owner.
Now its time for engine oil change and I want to revert it back to the manufacturer recommendation as using 10W40 engine oil and install thermostat valve back. i need expert recommendation from you experience fellows regarding below:
1- Engine is in perfect condition. should it is safe to use Shell Helix HX5 10w40 or any other your recommended oil as car is running for a long period using Caltex Havoline 20w50
2- Factory Radiator is also perfect and there is no water reducing or engine heat-up issues while using AC with auto fan without thermostat valve so is it also safe to install thermostat valve. also which one thermostat valve I buy? any recommendation regarding and price of it.
Thanks for your support in advance.