This is Why I Don't Change My Oil

[patrickt]

My last oil change was four years ago. I like to get yearly UOAs by Blackstone Labs and the one below came today. I look, of course, for wear particles, but I also look for anything that's in the oil that shouldn't be in the oil, like water, antifreeze and gas. That, along with the flash point, viscosity and TBN tell you whether or not you have a problem and whether you need to change your oil or not. The "I change my oil yearly for peace of mind" mindset is for idiots. Not to mention that SAE has papers supporting the theory that changing your oil too often actually increases engine wear. Zinc/Phos numbers can be misleading though because you don't know if that is "used" or not. But unless you have a solid flat tappet you don't really care about that as much as I do.

[mr bruce]

oil doesn't "wear out", it just gets dirty

[patrickt]

Originally Posted by mr bruce

oil doesn't "wear out", it just gets dirty

Well, kind of, but ZDDP does get used up, and gets broken apart, but you still have the same Zinc and Phosphorous elemental numbers, they're just not bound together the same way they were originally. It's like having the same amount of hydrogen and oxygen that you had when you started out with water but you just can't drink the two gases when they're not bound together.

[Harpoon PV2]

So be honest, how many of you had a self oil changing car or motorcycle back in the day? Cheers, Dennis

[Tommy]

Originally Posted by Harpoon PV2

So be honest, how many of you had a self oil changing car or motorcycle back in the day? Cheers, Dennis

Ok. Back in college I owned a 1952 Chevy van with a cracked block. I carried oil and water by the gallon. I think I got about a hundred miles per quart on the oil.

My EM Cobra didn't leak oil much but I did have an interesting oil change experience one day. As I was cleaning up afterwards I found the washer that I should have put on the plug before I screwed it back into the pan. I checked and, sure enough, the washer was missing at the plug. I wrestled with the ideas of dumping the eight quarts of oil I had just added and then finding some way to get all-most-some-any of it back into the engine without creating a huge mess. That was likely as the valve covers on my engine had big AN hoses to a catch can, but no normal oil fill. Putting oil in was a slow process using a funnel in one of the small hose openings. Then I remembered a story I had heard on the old Car Talk radio show. I decided to give it a try.

I began by getting out my shop vac and a length of clear plastic hose. I duct taped one end of the clear hose to the vacuum hose and the other end to one of the valve cover hose openings. I removed the other valve cover hose and taped that opening closed. I then stood well back and plugged in the shop vac. I waited to see if any any oil was being pulled up into the clear hose. It wasn't, and after a minute or so I decided the shop vac wasn't going to explode from engine fumes either. So I quickly slid under the car with the washer and a wrench. I loosened the plug and planned to live with whatever oil came out while I was replacing the washer. To my surprise air was being pulled into the oil pan with enough velocity to prevent oil from coming out. I replaced the washer, tightened the plug, removed my DIY vacuum system and went on with my day.

[mr bruce]

many moons ago in a galaxy far away, had an HD panhead, constant loss oil system, would mark it's spot at every rest, just like a dog and a fireplug. Scooter ran great, but the oil never got dirty enough to matter, it wasn't in there long enough.

[DanEC]

Well, the once a year mindset is for idiots, is a little strong. But I don’t qualify for that anyway. My oil change regimen is I, or Mr Holley or Mr Carter, usually screw something up with my carburetor and flood the crankcase with gas, thus an oil change.

[patrickt]

Originally Posted by DanEC

Well, the once a year mindset is for idiots, is a little strong. But...

Well, maybe. The idiot reference is aimed at guys on the threads that choose not to have their oil analyzed but instead change it ridiculously often and thus remain oblivious to what's actually in it.

[twobjshelbys]

Originally Posted by patrickt

Well, maybe. The idiot reference is aimed at guys on the threads that choose not to have their oil analyzed but instead change it ridiculously often and thus remain oblivious to what's actually in it.

How much does the test cost??? Walmart changes the oil in my car for $25 every 5000 miles...

[patrickt]

Originally Posted by twobjshelbys

How much does the test cost??? Walmart changes the oil in my car for $25 every 5000 miles...

But do they tell you if you have an unusual upward swing in your wear particles that will red flag a problem? Or if you have antifreeze in your oil when you never had it before? Why wouldn't you want to know that when a beautiful FE engine is a good $20k investment nowadays? Why would you just blindly change your oil without examining the evidence as to how your engine is doing? And btw, Blackstone charges $35 for the UOA and ten bucks more for the TBN. Jeez, if you've got to squeeze twenty bucks a year out then you're in the wrong hobby.

[twobjshelbys]

Originally Posted by patrickt

But do they tell you if you have an unusual upward swing in your wear particles that will red flag a problem? Or if you have antifreeze in your oil when you never had it before? Why wouldn't you want to know that when a beautiful FE engine is a good $20k investment nowadays? Why would you just blindly change your oil without examining the evidence as to how your engine is doing? And btw, Blackstone charges $35 for the UOA and ten bucks more for the TBN. Jeez, if you've got to squeeze twenty bucks a year out then you're in the wrong hobby.

It's just a Honda CRV with 26K miles on it. I've got OCD but not on car oil.

[patrickt]

Originally Posted by twobjshelbys

It's just a Honda CRV with 26K miles on it. I've got OCD but not on car oil.

Well I agree with that. I don't do it on my regular cars either. If the engine seized up on one of them I'd use it as an excuse to buy a new car.

[twobjshelbys]

Originally Posted by patrickt

Well I agree with that. I don't do it on my regular cars either. If the engine seized up on one of them I'd use it as an excuse to buy a new car.

It's a 2015 and we only drive it around town and the things we need most are only two miles away. The low duty cycle, high ambient temp (Vegas) and the horribly dusty air are why I change it at 5K. The new engines do get to operating temp much faster so even with the short drives it's at temp before we get there (stop lights that are always red add to the time). I look at the oil before and it's always clean as new. Honda says 7500 miles and their built-in "oil life" usually says 65-70% and that "system" supposedly accounts for the type of usage.

[Tommy]

Patrickt,
Where's a good place to learn the significance of all those data points? My doctor's lab report at least shows the normal range for every mysterious number it provides.

[patrickt]

Originally Posted by Tommy

Patrickt,
Where's a good place to learn the significance of all those data points? My doctor's lab report at least shows the normal range for every mysterious number it provides.

Go here: https://www.blackstone-labs.com/serv...t-explanation/
and choose Car, Airplane, etc. and they give you a nice little explanation of what different things mean, what creates what element ppm, etc. For example, the copper in my sample is the result of my oil cooler and can be ignored. What different element normal amounts are, etc. But I think you can take the same advice that my doctor gives me each year when he reviews my annual bloodwork. He's not looking so much at the actual numbers as he is looking that I'm pretty consistent from year to year and I don't have something new out of whack that can't be easily explained.

[patrickt]

And here is Schaeffer Oil's opinion on the numbers:

[eschaider]

I think we need more government control ...

[cycleguy55]

Originally Posted by eschaider

I think we need more government control ...

I hear Californians are crying for more regulations.

[patrickt]

I got a message asking for the SAE paper saying older used oil is way better than newer oil, so I'll just post it here:
https://www.sae.org/publications/tec.../2007-01-4133/

[eschaider]

Originally Posted by cycleguy55

I hear Californians are crying for more regulations.

This is the world's largest open air sanitarium, Brian. What else would you expect.