Finally I would really like to know how many miles of driving to change synthetic motor oil, not regular oil?

I have heard people tell me that it makes no difference whether its synthetic motor oil or regular motor oil and I should change it every 3000 miles and then I have been told for synthetic to change it every 10,000 miles. However, I have never asked a professional this question. So what is the true answer please and thank you for your help.Finally I would really like to know how many miles of driving to change synthetic motor oil, not regular oil?
i work at a quick lube and for full synthetic it is best changed at 5000 to 6000 miles intervals its not the oil that breaks down its the additives that break down been doing oil changes for about 10 years now and we have to know what we are sellingFinally I would really like to know how many miles of driving to change synthetic motor oil, not regular oil?
The only way to be absolutely sure when to change is to have an oil analysis preformed by a lab.





The military and many large transportation companies have done this in the past. My personal experiance is not to go any longer than 12000 miles without using premium oil filters and a lab test. I suggest not going any further than the vehicle manufacturer recommends even with synthetics. For example in my 1998 Jeep Grand Cherokee I change every 6000 miles with a semi-synthetic blend oil. Jeep recommends 3000 mile for severe duty and 7500 miles for regular service intervals with a conventional oil. Always change the oil filter with the oil.
It all depends on your driving conditions, your lead foot, the environment, its hard to tell exactly when you should change your oil. However with synthetic, it is usually good for 5K - 10K, my car has a oil life system and it tells me when to change my oil, i have 33K on my car now, i bought it new and only have done 3 oil changes on it. But I'm not hard on it like my other car, I do put full syn in and change around 3500. If your in dusty climate you should change earlier than if not in one. There is no magic number, people use baseline numbers to make it easy to remember when it needs to be done, I ran a shop that serviced a fleet, and did all gas engines at 3K and all diesel engines at 5K, just to be safe and make sure over doing it not underdoing it.








Hope this doesn't confuse you more, but informs you more. If I was you stick to around 5K just to be on safe side.
3000K same as regular oil. the 10,000K is rediculous... i would never do that to my car, i do every 5000 with synthetic. After 7000K the synthetic oil looks like crap and feels like water, it's not lubricating very well. 5000K is still feels slippery coming out of the vehicle.
5,000 is best. synthetic is very costly and oil change intervals should be reflected on the price. why pay 4.50 a quart and change it 3,000 miles later? stick with 5,000.