I have been thinking about going sythetic for some time. Have you guys ever tried out a by-pass filter? I heard that these filters, Frantz in particular, can help filter out very small debris and also gasoline.

I have been holding off on sythetic because of concerns about gas dilution.
My theory is that even in the best engine, a bit of gas is mixed in with the motor oil. So if I am going to be using synthetic and increasing change intervals to 10k or 15k, then the synthetic oil will be too contaminated.

What are your thoughts on this ?
Is the by-pass filter necessary?

I have an AMSOIL bypass filter on my 1985 Volvo 245 turbo.
If you are driving a lot of miles every year, or driving a diesel, or have a fleet on the road, or using equipment 20-30 hours a week, a bypass filter is a super idea.
If you are driving 12-15,000 miles a year, and plan to keep the car many years, a bypass filter certainly wouldn't hurt anything. I wouldn't extend the oil drain past 1 year without using oil analysis--and that makes the bypass filter about equal to just changing a good synthetic (such as AMSOIL) every year.

A good bypass filter will remove very small particles and water. You should be able to use the oil about 3 times longer than normal, assuming a sound engine. The only way to be sure is with periodic oil analysis.

I use synthetic oil in my car with no problems. My car is a high milage car. It was over ten years old before I got it and the milage was unknown. I switched over , after a flush, and I have had no oil problems. I changed a car with a bypass filter installed and was amazed at the big differance in weight with all the loose oil removed. This filter was on a fairly low millage car and the owner changed the main and bypass filter twice a year. I haven't installed a bypass on my car as of yet, but the weight sold me.

Eck Sheppard 81 242