The surprising truth about motor oils

Skyco · Jun 27, 2008

plowking said:
I heard on the radio,that it is encouraged to do 3000 mile oil changes to keep the mpgs up. Maybe cleaner oil gives better mileage? plowking

Was that a Jiffy Lube ad?

Wayne County Hose · Jun 27, 2008

I will continue to waste my money and change at 3500 miles. I also change all of the fluids in all my vehicles yearly. This includes tranny, diffs, coolant, brake fluid, etc. I have absolutely never had a component go bad. Not so much as a water pump. I have driven my personal and company vehicles well in excess of 1,000,000 miles. I had many vehicles over 200,000 miles. I've changed alternators and starters, but never a component that depended on the fluids I change at least yearly. I worked in an engine rebuilding shop and have been a mechanic for over 22 years. I would rather spend my money on fluids on my schedule than on components whenever they feel like breaking.

My reasoning is this. When you have your oil analyzed, and they tell you it has 50% life left, well, to me that oil is also 50% dead. I don't want oil that is only 50% good in my engine. In a 6 quart system, that's like having 3 good quarts and 3 bad quarts.

Also, sure, Jiffy Lube wants you to just change the oil at 3,000. They make more money. But, the lab also wants you to keep sending oil samples. You change the oil, you stop sending in samples for a while. That's why they tell you, "20% oil life left." Not, "80% oil dead."

Dargo · Jun 27, 2008

Wayne County Hose said:
I will continue to waste my money and change at 3500 miles. I also change all of the fluids in all my vehicles yearly. This includes tranny, diffs, coolant, brake fluid, etc.

Even though I don't change my oil or fluids quite that frequently I do believe a guy could spend his money on worse things.