If u have let's say 10-30 in u car and to top it off u put a quart of 5-20 in wat happens does it make the overall weight of the oil less? Is it bad to mix oils? Iv done this plenty of time with no problems but I'm just wonder

 

I will start the discussion by referring to 2 of my favorite oil articles. They are long reads but explain dino oil, synthetic, and additives. You would be mixing additives, especially in different brands. Probably of little consequence if you change oil frequently, before additives wear out is my short answer from the articles and seems like your experience. Long answer is in articles below.

http://www.boss302.com/oil.htm

http://ferrarichat.com/forum/faq.php...tor_oil_basics

 

wow i didnt read all of that cuz its alot but theres alot more to oil than i thought and ill never use anything over 10-30 again lol. i feel like an idiot cuz i used to put thick *** oil in my SRT just cuz it was turbocharged. dam kinda makes me wanna go change the oil in my teggy now. ill finish reading latter when i get home. good articles!