Just remember the manufactures are in the business of selling new vehicles, their maintenance schedules in the manuals are designed to get the vehicle past its warranty period. If the vehicles were to last a long time, no one would buy new ones. Think about that. I'm one who swears by 3K engine oil changes and have torn apart engines that had zero gunk or even cylinder wear at 150K plus. Engines still had the factory crosshatch in the cylinders and zero wear at the top of the cylinder wall.[/QUOTE]
I'm not saying you're wrong, in suggesting that 3K oil changes will result in less engine wear than 15K 10K 5K or a larger number than 3K .... However ... from a technical standpoint isn't that equivalent to saying "I always fill my gas tank when it's 1/2 empty and I have never run out of gas" ?
How would they know that 3/4 or 1/4 empty would have the same result as 1/2 empty?
Now I know this math doesn't apply to home mechanics but but for people who have their oil changed at a shop ... if life of engine is 300K and oil changes cost $60 ... 6K oil changes will save you 50 oil changes vs 3K or $3000. The 3K oil change interval is a $3000 insurance policy.[/QUOTE]
There are nany different ways to look at it. And all theories can have some merit. There is no one right or wrong answer as some people want to make it seem.
The fuel filling and start entirely different debate. I have a friend or two that gripes at me all the time because I run every car I own all the way until 0 miles till empty until I buy gas. I rarely have fuel pumps fail.
Last one I had go out was in 2015 on a 2000 vehicle so it wasn't like it failed prematurely.
There is some argument that allowing the sending unit to work at least 90% of its full range is better for it then only allowing it to move a lesser amount.
I will say that the worst thing you could do for the sending units especially GM's cuz they have all kinds of problems with them would be to put it at one spot let's say right on half and add gas every two days to your vehicle so it always sits in the same relative small spot and moves back and forth.
I have taken GM's apart and seen the small fine wire wrapped around the basically piece of cardboard like plastic and scene where the little finger has worn Through the Wire.
I was able to use tweezers to wrap it back together and solder it and get the sending unit working again. It wasn't quite as accurate as before but it was within 10%.
That part wasn't available new or from the dealer As A Separate Peace and I certainly wasn't going to buy a brand new fuel pump just to get the gas gauge to work.
I ran a 40 foot MCI Diesel Pusher bus for over 3 years that didn't have a fuel gauge. It held 144 gallons and I never once filled it up.
I did run out of gas twice before I figured out to grab me a stick off a tree and break it off just the right length. I would stick that in the tank all the way down and pull it out to see how much gas I had left. If I had under 3 inch on the stick I better get some diesel.
I didn't run out after that. It doesn't hurt them to run out of fuel but it's annoying the way you have to Prime them to get them to start back.
Now let me tell you the ultimate paradoxical story about oil changes or lack thereof.
I bought a truck with a V10 Ford in it from the original owner with 86000 miles on it in 2007 July.
Apparently he never changed the oil because it was 3 quarts low when I bought it. It was barely on the tip of the stick and the things hold 7 quarts if you fill them to the full mark.
But it sounded great and ran perfectly for the twelve hundred mile trip home.
It was also 3000 to $5,000 under market value so any issues or a moot point.
Now I didn't drive the vehicle the whole lot. The most I ever put on it with 7-8k miles in one year but most were no more than 5,000 maybe 6.
Now we all know about amsoil cllaiming 15 or 20 thousand mile oil changes and for the past good number of years mobile one with their extended oil claims 15000. This was back in 2007 so I'm not quite sure the mobil one was pushing that at the time.
But you get the idea that it's becoming more and more acceptable for these long-term oil changes so... It didn't make me feel too bad when I neglected what used to be my normal oil changes.
So by December of 2013 I think I had change the oil three times, for If I was lucky, or if it was lucky. Now I had probably added a quart several times during that time frame but I don't think I ever ran Marvel's or anything like that.
Now had I been doing a proper maintenance schedule like I used to on all the cars I really cared about oh, I would have changed the oil at least twice a year. Minimum. If I were putting a lot of miles on it I would have changed it every four to five thousand.
I always ran full synthetic and this usually mobil one.
I do the oil changes myself but even at Walmart I ended up buying to 5 quart jugs because it's just a rip-off to buy one or two singles and at the prices at the time it was about $23 for each jug and then $4 for the filter. So about 53 for an oil change. Because I never end up having that oil left over when it's time to change it again. When you top off a V10 all the way to the full Mark which I do ends up being 7 qts despite what ford or anyone else says. Their recommendation only puts you a quarter to Half Way in the crosshatch mark. Even if you have the proper dipstick because yes, there was a TSB on some of those but not on this particular engine.
I would end up using the oil for top offs for multiple cars so it was cost me $53 maybe 55 for an oil change Plus about 30 to 45 minutes start to finish to do it all and clean everything up.
Okay, now the fun math part.
So I rarely ever change the oil and around December 14th or whatever Saturday there was there a couple weeks before Christmas, the engine seized up with a hundred and thirty-three thousand miles on it.
So I went from 86000 to 133 in six and a half years.
Now I really don't know if I would have got any longer life out of it had I have changed the oil religiously but if I would have known there was such a sludge problem or a caramelized hard bricked up peanut brittle looking stuff inside the engine valve covers, I could have used an engine flush twice and Marvel's Mystery Oil and maybe, just maybe, the pickup tube would not have gotten clogged up and I could have drained the crap out and it wouldn't have blown up or at least would have lasted longer.
Had I've got another four to five years out of it the engine could have gone to the junkyard with the rest of the rusty vehicle.
But back to the math part, $53 / oil change Plus on average let's say 42 minutes of time.
If I had done it like I used to that would have been at least 13 oil changes even just based on time.
That's $689 not counting if I had to maybe buy a new oil change drain pan or maybe oil plug gasket or two.
But we'll stick with 689.
And total time spent for all the oil changes would be 9.1 hours.
So I was a slacker and didn't do any of this and lost an engine. So as I said I don't use the vehicle that often but I did need it occasionally and certainly couldn't sell it for much with a blown engine so I pushed it home bumper to bumper and I priced several engines and they were going for between 1200 $2,000 for decent used ones.
I wasn't in a hurry so I waited and one day about 4 months later one popped up.
50 miles from home like I had a low mile one out of a recently wrecked moving van with the transmission for the low low great price of $500.
He even had a stack of Maintenance records and it had one mobil 1 its entire life because his son-in-law was the opposite of me and was quite OCD about taking care of vehicles.
I kind of had to convince the guy to let me go get it that night because it was getting late but I didn't want anyone to buy it out from under me. So I got there shortly after dark and he was a super nice guy and he loaded it up for me on the back of my truck with a bobcat he owned.
He knew he was selling it cheap and he said his son-in-law even said he should ask more but he said he just didn't care, I think he got an insurance settlement and he just wanted to help someone out. I thanked him immensely and still do.
So I bought the engine for 500 with the transmission remember, went and bought a cheap Harbor Freight engine hoist for $100 with the coupon since the last engine I did was 15 years ago or more in a jeep and we just picked it up with a tow strap and a steel pipe and set it on the frame because there were no fenders on the Jeep CJ5 and when I was in my teens switching Motors in GTOs I would just go two blocks up the street and rent an engine hoist for like $26 for 4 hours.
So I bought the engine and transmission, the engine hoist, oil pan gasket, exhaust manifold gaskets, 20 new grade 8 bolts and lock washers for these manifolds, intake manifold gasket set, new oil filter, 2 5 quart jugs of full synthetic oil at Walmart, and two gallons of Prestone antifreeze. I also had to buy an 8mm tap and some new drill bits to drill out for the exhaust manifold studs that broke since I was replacing the gaskets since I had the engine out because these things are known to have gasket leaks.
The thing had fresh plugs in it because it was highly maintained and I just checked them to make sure number loose and one was a little looser than I would have liked but everything was good there.
Total expenses were 746.99. I have it all written down because I'm lazy but I'm a numbers cruncher.
So then since I had this awesome 5 R 110 transmission that goes behind the big diesels , and I had no use for it, I sold it in 3 days for $375 to a guy in Columbus. That was a really good price and he was happy to quickly come get it.
So I just kept the good cheap parts wheel turning from the engine seller to me and to the guy with the transmission.
So I had $371.99 in an engine replacement.
That's $317 cheaper than if I would have done the oil changes myself!
It's crazy, and I really wouldn't recommend doing it but the numbers don't lie.
Sadly, this reminds me a lot of the new theory on lawn mowers and outdoor power equipment, they're all disposable. Briggs & Stratton says never need oil changes. They just want you to top it off and when it blows up by another one.
Now just to be accurate let's figure in labor rate for my time. It would have been 9 hours a time to do all those 13 oil changes and it did take me longer than 9 hours total to do the engine swap. I had one hour there in one hour back to buy it, I have one hour to go by the engine hoist. Of course that's something I will have for the rest of my life. I had a couple of hours and the trip to drive the drill bits and the parts at the parts store and the oil at Walmart.
But I had a few extra hours over the 9 to do the whole job. It took about 45 to pull it out since I never pulled one out of an Excursion before and it's kind of tall and the engine hoist is kind of short. That I had three or four hours of engine stand work and clean up and then it took me five or six to put it back in.
But I probably didn't have over 10 extra hours in it versus just doing as all changes because it did not figure the time going to the store buying the oil filter and oil for the oil change in with the oil changes which you would if you wanted to be highly OCD and accurate.
But the $317 depending on what labor rate I want to pay myself or claim I'm worth equates to over 10 extra hours labor at $30 an hour. Most mechanics don't make $30 an hour. A lot of guys that work at home on the side charge that because that's a great deal since garages charge 75-110 but the mechanic is lucky to get 25 tops.
So by the math and even by the time because most people don't make $30 an hour at their real jobs not. I had an overall better Financial experience my neglecting the engine and not doing oil changes and then replacing the entire engine and I ended up with an engine with 25k fewer miles!
It's absolutely crazy ass-backwards way to do it but it does prove true on paper.
The main reason was though because I was very lucky getting that deal on the engine and transmission.
So as with everything in life I always say it's all relative. Relevant to me finding that deal that it just dropped in my lap. Relative because who's to say the first engine would have ever blown up really. Relative to if I might have used Marvel's and changed the oil more often it might not have blown up or it might have dislodged a bunch of Gunk and clogged up even sooner. I could have lost an engine in 3500 miles. You can lose an engine right after putting some of that fast flush in it.
So who knows???
But them's the facts as I experienced em.
It's probably just my best way of rationalizing my crazy extra amount of work but when you really look at all the numbers... I actually came out ahead in all areas.
Do I want to do it again, do I plan on going through this with other vehicles? No I do not. Because easy and comfortable is better fan risky, unknown timetable, and not guaranteed similar Financial outcome.
Good money and good bet is on taking care of your stuff and using a decent or high quality motor oil and not letting it go past 6000 miles and even more importantly don't let it get low because if you're letting your oil get extremely low down below the add Mark or barely on the stick whether it's three thousand miles or six thousand miles, you are really contaminating, coking, and burning up the oil that's in there.
I feel that the bigger problem with higher mile intervals between oil changes that actually just the higher miles. If you're always on the full mark and you go 7500 miles is not nearly as bad as if your oil is a quart to a quart and a quarter low and you go an extra 2000 from let's say 3000-5000 with it being low.
Sorry for another book but you guys know I'm a wordy SOB.