"sf" > wrote in message
>> >
>>
>> Depends on how the car is driven. I've used 7500 for years now and with
>> 200,000 miles on a few, no problems. If you drive 3000 miles a year,
>> yes,
>> that is a good interval.
>
> New cars use synthetic oil, so they're only changed once a year or
> 12,000 miles.
>

Some use synthetic, but not all. Yes, it does increase the interval and is
actually a better lubricating oil. Many years ago we did some testing on
very small engines and the synthetics worked wonders. The only advantage
for most cars is the extended change interval. Very few cars today have oil
related problems like they did many years ago and 150,000 to 200,000 is
expected with normal oil. About that time, the rest of the car is getting
tired.