What motor oil does a 2002 Trailblazer take?

Answer 1

Answer5w-30 is the viscocity.

The type of oil is debatable and based on length of in service time. If you are going to use the Oil Life Management system built into the truck then you should use sythetic based on its abaility to hold and suspend contaminants and the high level of quality additives. Be sure to use a long life high quality filter like a Mobil 1 or other specialty filter.

If you use Dino Oil (Regular) then then most users prefer to limit themselves to the 5000 mile limit and not pay attention to the OIL Life Management System. Some users go 3000 miles and dump it but given the advancement of todays oil that is excessive.

Having said that, GM has invested Millions into the oil life management sytem on their vehicles. Some Treailblazer enthusiasts use that regularly and only change the schedule if they tow during the summer etc. as described in the owners manual.

Lots of info about oil types and testing can be found at the Related Link.