Every Manufacture has diferent recommendation, typically ranging from 8000 miles to 12500 miles
If it is the synthetic blend, you should change the oil every 3,000 miles. If it is a full synthetic, you should change the oil every 5,000 miles.
Every 3,000 miles Ford recommends every 5,000 miles with normal oil or synthetic blend. You can go up to 7,000 if you use full synthetic.
If you drive normally and use full synthetic you should change your oil every 8,000 miles. You should change the filter at the same time and change your air filter every 30,000 miles.
The best oil is 10w-40 full syn. If you go by the oil change indicator lights, use full synthetic. If you change it at half the interval, regular oil is okay, but I still recommend full synthetic. It should have a rating of ACEA-A3 rated.
For the 2003 1.8T Audi TT you should consider oil changes every 5,000 miles with full synthetic oil as turbo charged engines run hotter when enjoyed. Also, always change the oil filter when you change the oil.
You can mix part synthetic oil with full synthetic oil.
I usually use 10W-40 full synthetic for summer season and 0W-40 full synthetic for winter season.
Who told you it was not good? You can and should use full synthetic in a 150cc air cooled engine.
5w30 full synthetic
Every 3,000 miles is when the oil should be changed on a motor vehicle using standard oil. If the vehicle takes Full Synthetic, 5000 miles is the oil change interval.
For a 2011 Acura MDX, it is recommended to use 5W-20 motor oil that meets the API certification for gasoline engines. You can choose between conventional, synthetic blend, or full synthetic oil, with full synthetic often providing better performance and protection. Always refer to the owner's manual for specific recommendations and oil change intervals.
FWIW, my Honda dealer here in Mpls told me the Honda brand 0W20 oil is SEMI-synthetic and NOT full synthetic. That seems logical to me because they charge $39 for a 0W20 oil change and to get full synthetic almost anywhere it cost you around $60 for an oil change. Full synthetic Mobil 1 0W20 cost $6.50 a quart at Walmart, so you are already over $33 just for the oil. Add labor and a good filter and your at the $60 mark.