I have a 2005 z71. What weight motor oil should I use?
Should be wrote on oil cap or decal under hood, If not you can call parts store, most can look it up. The reason you need to run thinner weight oil in newer engines (1990"s and newer) is the oil clearance and passageways in engine are smaller. the old 10w-40 and 20w-50 will not flow to or around bearings. This causes oil to break down fast and engine is going to be damaged. Very important question you asked.
Well put southern mechanic. The new Toyotas use strictly 0W20
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