I live in the northwest, particularly in the Chicagoland area. I am going to change the car over from regular oil to synthetic. What weight/viscosity oil should I use. I am used to using 10W-30 regular oil in my other cars, but I've been hearing of people using much higher viscosity oils, such as 0W-30. What should I use for my area? I've also found an Amsoil dealer near me, so I might try the stuff, but I also heard that Valvoline synthetic keeps the seals moist, and helps with the cleaning of the engine, and re-vitalizing the seals, so as that you don't get any leaks, or much less. What kind should I be using. The car that I purchased has 140k on it. Thanks in advance.

 

I would say to go with either castrol or the Valvoline in a 10w-30 in the sythetic.

 

One more question Mr. Tech. I am a little bit worried about putting synthetic oil in my car. It has 140k, but the engine does seem to knock a little louder than most of the cars that I've had. Also, I would like to make it last, so I thought that synthetic would be a good choice. However, with all that you have read about my car, and the possible leak in the rear seal, would it be wise to put synthetic in? I may be asking for a lot more leaks. And, i know what i've read about the Valvoline rejuvinating the seals, but i'm still not sure. What do you think? I know that you don't know that much about the car, but with everything that i've written, would you say it's a good choice to use the synthetic, or not?

 

I would say to go for it.I am one to go with synthetic.I have seen it done many times with no problems at all.You should not have any problems at all.If you develop any oil leaks it will be because the seals are bad.

 

Thanks, I'll do that.