First and foremost - I'm sorry, but I didn't know where exactly to put this thread! Now, there have been a number of things that have crossed my mind and have wondered what the answer was to these unasked questions. For vehicles with a manual transmission, what's healthier for the vehicle in general: slipping the clutch for a smooth shift while shifting up or down (mostly down that I'm wondering about) or just engaging the clutch fully and immediately? Most of the people I've been in a car with (with them driving) just let the clutch pedal out immediately, and naturally the car jerks because the clutch is suddenly engaged. I get particularly irked when someone's downshifting and they just let the pedal out without even trying to make it a smooth downshift. Which method is healthier for the transmission components: slipping the clutch or making sudden clutch movements? Second, there are those people who drive their cars hard and others who drive like grannies and never rev their engines. What is healthier for the engine: shifting in mid rev range or shifting down low? I ask this question because I noticed that if I'm in say 4th gear on the street doing about 30mph and I floor it, naturally the car has no go as it's not in the right gear and powerband, but as it accelerates it gets much better fuel economy than if I was to downshift to second and give it the beans. Is this "economy" acceleration hurting the engine? How stressful is it to the engine? Is it less stressful to rev it to redline and shift or to floor it in a high gear?