Is the Vortec 5300 LM7 reliable? I would like to hear the opinions of engine experts if there are any on our forum. I see a lot of reviews on the internet, both good and not so good. What do you think? On the https://www.wersis.net I looked at the description of this engine in detail. I am interested in the 2004-2007 (299 PS (220 kW; 295 HP) model year.