I live in Wisconsin and run 10w 30 in the summer and 5w 30 October through April when its cold. My cap says 5w 30 but I like the thicker oil in the summer. I always run mobil 1 and have had great luck with it.
yeah my truck calls for 10w30 so i think ill stick with that. i was talking to someone who says they dont like to switch oil brands too often but im taking my truck to juffy lube for an oil change pretty soon. you guys think it will be fine if i switch to a synthetic such as mobil or royal purple from the conventional ive been using?
2000 5.3 Silverado: Flowmaster True Dual Exhaust, Glasspacks, Poweraid TBS, descreened MAF, K&N Filter, JL Sound System, Prestige alarm, All chrome grill, Spray On bedliner...more to come
New Addition to the family: 2009 Dodge Challenger R/T
Once you use conventional you can't use full synthetic oil only partial. Once you use conventional oil it swells the engine gaskets. Using synthetic afterwards will cause these gaskets to shrink to the point where they no longer fit tight between the metal parts and now you have leaks. So conventional or half and half only.
99' Silverado 5.3 4X4
Modified Predator 93 tune: TQM @ 40%, injector slope bumped up 4 levels,
125 MPH top speed, 5500 RPM limit,
TBS, 180 thermostat, 4" CAI with 9x6" element,
Bypass and De screen performed,
AVG: 16 MPG City, 20 MPG Highway