Man, even 25w50 or 15w60 is too thick IMO.
I don't get any cold start noises either, BUT YOU MUST USE GENUINE GM OIL FILTER. Not ryco or any other generic after market filters. Can't remember which MAG it was , but they did independant testing on all the A/M brands and genuine filters from the different car manuf. ALL A/M brands came up as being poorly made with too much cartridge jammed in the filter cannister. They showed pics of the different filter cut through to reveal the quality of each. Genuines were made to fit. Difference which was my own first hand change from A/M to a genuine filter was MASSIVE. Cold starts and lifter noise was gone as soon as I put the genuine filter on (Had just done the oil change and used Castrol Edge 5W30 then read about it so with same oil changed the filter to genuine) .
Yeh totally agree when it comes to filters,it amazes me when people spend big dollars on high cost synthetic oils only to put a cheap and nasty $2 oil filter on,then complain about the rattle at start up,and the lack of oil pressure when the engines at operating temp.
I dont know if alot of you are aware that Ryco were once the choice of choice when it came to after market filters, BUT they are now made overseas in bloody CHINA !!!!!!!!!!!!!!!!!!!!!!!!!!The filter media is probably leftover off cuts from the bonds t-shirt company.
Just out of interest I have tried a filter manufactured here in Australia made by a company called WESFIL. If interested here is their web site.
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