oil changes

CKNSLS wrote:

handsome51 wrote:
I thought I would add my 2 cents. I will agree that the oil today is way better then it use to be in the 60s and 70s. Back then when a engine had around 75.000 miles on it . You would see it smoking going down the road. Back then you had to change your oil every 2,000 miles if you wanted your engine to last. I am still a fanatic on changing my oil. If I use mineral oil, I change it every 3000 miles. If I use synthetic oil I change it every 5000 miles. I know I could go longer on the synthetic oil. In fact in my diesel I use amsoil heavy duty synthetic diesel and marine oil with the amsoil filter. According to amsoil using this oil and their filer I can go 20.000 miles or 1 year between oil change. As often as I change the oil I could use their cheaper synthetic oil and be just as well off. But this is what I go by besides humans are creatures of habit. Back in the 60s when my dad was changing oil every 2000 miles. He said son, a oil change is the cheapest motor overhaul your ever going to get.I said to myself, he is right.Like I said ,I do go overboard on the oil change intervals . But like my dad said it is the cheapest motor overhaul you are ever going to get. Plus when you do have to work on my engines. When you pull the valve covers or the intake. The block looks like brand new with fresh motor oil poured down it. Their is not sludge.

If you do it (change oil) based on habit-that is one thing. However, you could go longer on both conventional oil and synthetic oil without any issues whatsoever. There are plenty of UOAs over at bobistheoilguy.com that PROVES what I just suggested to you. Oils are a entirely different product today than they were when your dad was working on cars.

Yes, today's oils are better but are there less combustion byproducts or dirt in the crankcase? I would venture to say, yes, todays engines operate on closer tolerances and there are better materials, machined to a finer product. I'd also say that the difference is not 50%, 30%, or even 20% less contamination of the oil. Today's oils will have less friction over the duration but they don't do that much better of a job removing the products that cause engine wear.

Ask a SAAB owner about oil change intervals. SAAB made a huge error by putting the interval out to 15,000 mi. With the 9-5 warrantied to 100K mi, it hit their bankroll hard when all of the engines failed in the warranty period. They soon found their mistake and lowered the interval to 10,000 mi.