Actually found the oil info, forgot we got service paperwork from them. 5W30 motorcraft oil. Oil filter is part number R84060. Doesn't mention brand but google search brings up Carquest
Thanks for the quick reply! We are taking it to a 3rd party mechanic for them to go over it tomorrow. We will make sure they check it with a manual gauge.
So I'm looking at a 2007 yukon denali 6.2L possibly to purchase. All in all seems solid except for the oil pressure seems really low at idle. I know these dash gauges aren't the most reliable but this seems concerning. 6.2L guys what say you?