20 weight in the Grand Marquis 4.6 2V (Magnatec full syn 5W20), no noise, oil pressure, nor consumption issues. The last 3 company vans (E-250 4.6 2V, 2015 Transit 250 3.7, & 2018 Transit 250 3.7) are/were 5W20-unfortunately the new one lost a quart in its first 6500 miles, but the other 2 didn't use a drop in 100K. My mom's '06 Matrix also has 5W20 (back specced)-she never drives anywhere far, so it won't matter. 5W20 will give a slight MPG improvement over 30 or 40 weight-IF the engine is designed to handle it (& isn't worn enough to have oil pressure issues).