Change your damn oil!!

When I had my 91 F350 7.3L Diesel, you had to change the oil at the 2500 mile mark, it was already very nasty and reeked of diesel fuel. Surprisingly while Diesel is good at cleaning, it is equally as good at making a crankcase one nasty smelly place.

I have also helped a friend pull apart a 305 (GM Goodwrench replacement engine) out of a car he was working on, and while under the valve covers was okay, we couldn't get the pushrods out. So we pulled the intake and the entire lifter valley was full of hard black tar like crap. We had to pull the heads to get the pushrods out. We had to pull the bottom end apart to get the lifters out. Someone definitely didn't believe in changing oil.

Crankcase ventilation is a BIG factor in oil longevity. If the engine is not able to effectively remove the moisture and contaminants that vaporize out of the oil, they will end up back in the oil, and in ever-increasing quantities. Changing oil frequently can mask CCV issues.

Fuels & Lubes class back in college had us doing oil testing, cooling the stuff until it wouldn't pour and Tech2000 branded oil from Wal-Mart started getting waxy way before anything else did, something around 15F I think, which meant it wasn't quite meeting the temps implied by the labeling. 0-30 Mobil synthetic was pretty impressive, we couldn't get it to not pour using dry ice and seeing temps around -50F. We basically ran out of cold before it was solid.

MrJoshua wrote: Even at 15000 miles how do you turn oil into a gelatinous substance?

Easy. Use a "Qwik-Luub!" place that doesn't actually change your oil. Voila! 30,000 miles!

mguar wrote: In reply to Knurled: It's not miles, it's time as well. Now short hauls or stop and go sort of driving calls for more frequent.. yes as soon as 3000 miles or sooner depending on how much time has passed..

so gazillion year old dino-sauce is gonna go bad in a few months, just because? no, its pretty much sheer friction/mechanical use that causes oil to need replaced, and really, as I stated earlier, the oil itself is just fine, its the fact that after a couple thousand miles of mechanical use, its full of crap, and doesnt lubricate as well. Remove the crap, and the oil is really fine to keep going. The "3 months" part of the "recommended" oil change interval that was jammed down the American public's throat over the last 5 decades was put there to remind soccer moms to get off facebook for 5 minutes and take the car in for an oil change, since most dont even know what an odometer does, let alone look at it.

Through the early 1960's, 1,000 miles was a common interval, in the mid to late '60's the max interval was stretched to 4,000. Now it's commonly 7,500 with conventional oils with the odd super long one for synthetics. Nobody will deny that both engines and oils have gotten better, so the oils and metallurgy of the '50's and '60's have no real relation to current oils. Just keep in mind all these are MAXIMUM intervals!

I make a living selling service and oil changes do not make me a damn dime, not even the megabux synthetic ones. They kill my average per RO (service advisors know exactly what I'm talking about). Yet I still advise intervals shorter than the max because after all I have seen I cannot, in good conscience, recommend those max intervals. If Mr or Mrs Customer decline after I explain, well I tried. If their engine saws itself open and they have to tap the kid's college fund to fix it then my conscience is clear.

With todays oils, no way would that happen in 15K miles under normal use. If the vehicle was driven 5 blocks and shut off to be driven 5 blocks again could be a factor though. Not getting the oil up to normal temperatures to burn off the moisture will cause sludging. How long a time did it take to achieve the 15K miles. Good rule of thumb, never run your oil for over a year.

My ford 2011 Fiesta says to change oil at 10k miles or one year, whichever comes forst. I will soon be doing my 3rd oil change at 30k miles. I use a quality synthetic oil.

I ran 7500-10k in the redline when I switched to royal purple......it was still a light amber at 5k. Mobil 1 full synthetic was black by that same point.

I've been running amsoil in the '91 since I bought it......6k miles, but I've changed it twice now. The bmw ought to be fun......and will recieve a new change to the donor engine.....might go with motul, the blood of baby seals never hurts.

We have a Juke here at work that came in for an engine rattle. It has 32k kilometers on it, and has never had the oil or filter changed. Took the timing cover off and found the tensioner fully extended and the chain very loose. Further tear down revealed all the cam journals scored. The oil itself was not low at all and other than being very black had no sludge and flowed normally. They're getting a used engine put in next week....

I saw an almost identical issue, but this was a Grand Cherokee with 68,000 miles on the original oil and filter!!!

yamaha wrote: I ran 7500-10k in the redline when I switched to royal purple......it was still a light amber at 5k. Mobil 1 full synthetic was black by that same point.

Don't assume black means sludge. M1 used to be very good at holding stuff in suspension so it could be delivered to the filter.

Send you oil out for analysis. It is really the only way to know if it is done (unless you need a spackle knife to scrape it out of the pan :) )

Curmudgeon wrote: I once saw a Kia Rio with 9,000 miles with a complaint of engine rattle. The oil had not been changed. The oil at the bottom of the pan looked like chocolate pudding, when the drain plug was removed you could see the stuff but it wouldn't come out.

1.6? I'm fairly sure this is the same engine.

It's hard to compare an engine that spends most of its life at WOT because it's a small engine in a hyper-tall geared car, versus a large-engined car that barely loafs along, hardly strained at all.

4cylndrfury wrote:

mguar wrote: In reply to Knurled: It's not miles, it's time as well. Now short hauls or stop and go sort of driving calls for more frequent.. yes as soon as 3000 miles or sooner depending on how much time has passed..

so gazillion year old dino-sauce is gonna go bad in a few months, just because? no, its pretty much sheer friction/mechanical use that causes oil to need replaced, and really, as I stated earlier, the oil itself is just fine, its the fact that after a couple thousand miles of mechanical use, its full of crap, and doesnt lubricate as well. Remove the crap, and the oil is really fine to keep going. The "3 months" part of the "recommended" oil change interval that was jammed down the American public's throat over the last 5 decades was put there to remind soccer moms to get off facebook for 5 minutes and take the car in for an oil change, since most dont even know what an odometer does, let alone look at it.

Oh! I took it to mean time: I can drive up to a gas station and pump gas in it while it idles. Eventually the oil would break down. Even though the odometer hasn't clicked over a single mile. That sort of time.

We used to install engine run timers on the squad cars because they would sit an idle so much. I don't remember the ratio but the the hours of run time per mile was ridiculously skewed. I could see how a customer who ran their car to melt ice or warm up or cool down the cabin could accumulate a ton of run time in 15K miles.

In reply to Johnboyjjb:

With a service vehicle, I could see that being the case - hours running vs miles driven being way skewed. But your typical grocery getter isnt going to idle that long.

MrJoshua wrote: Even at 15000 miles how do you turn oil into a gelatinous substance?

Well, new Honda 3.7L V6's just turn oil into a solid chunk of burnt sludge and burn up the bearings in 15k miles. We've had 3 so far that ranged from 14k-17k miles on the oil change that required an engine.

Knurled wrote:

Curmudgeon wrote: I once saw a Kia Rio with 9,000 miles with a complaint of engine rattle. The oil had not been changed. The oil at the bottom of the pan looked like chocolate pudding, when the drain plug was removed you could see the stuff but it wouldn't come out.

1.6? I'm fairly sure this is the same engine. It's hard to compare an engine that spends most of its life at WOT because it's a small engine in a hyper-tall geared car, versus a large-engined car that barely loafs along, hardly strained at all.

That's the one. The fact that engine 1 (9k) survived being driven ~40 miles at highway speeds to the shop and engine 2 survived ~31k miles of being driven with the original oil and filter speaks to how tough the little things really are.

Johnboyjjb wrote:

4cylndrfury wrote:

mguar wrote: In reply to Knurled: It's not miles, it's time as well. Now short hauls or stop and go sort of driving calls for more frequent.. yes as soon as 3000 miles or sooner depending on how much time has passed..

so gazillion year old dino-sauce is gonna go bad in a few months, just because? no, its pretty much sheer friction/mechanical use that causes oil to need replaced, and really, as I stated earlier, the oil itself is just fine, its the fact that after a couple thousand miles of mechanical use, its full of crap, and doesnt lubricate as well. Remove the crap, and the oil is really fine to keep going. The "3 months" part of the "recommended" oil change interval that was jammed down the American public's throat over the last 5 decades was put there to remind soccer moms to get off facebook for 5 minutes and take the car in for an oil change, since most dont even know what an odometer does, let alone look at it.

Oh! I took it to mean time: I can drive up to a gas station and pump gas in it while it idles. Eventually the oil would break down. Even though the odometer hasn't clicked over a single mile. That sort of time. We used to install engine run timers on the squad cars because they would sit an idle so much. I don't remember the ratio but the the hours of run time per mile was ridiculously skewed. I could see how a customer who ran their car to melt ice or warm up or cool down the cabin could accumulate a ton of run time in 15K miles.

Women tend to think in terms of time for this kind of thing, men in miles and it's necessary to convert the figures. For instance, I had a lady this AM who wanted to know if her daughter's tires would last till Christmas. I told her our best educated guess was another 5k miles, she repeated her question of 'till Christmas?'. That meant I had to convert the miles into months so she'd be clear on it. Her daughter drives ~2k a month, meaning the tires won't make it till Christmas.

Since the average person drives ~1000 miles per month, the 3/3 isn't as farfetched as it seems. OBTW: that 1k/month average is the basis for the 12/12 warranty period and its multiples of 36/36 etc.

Curmudgeon wrote:

Knurled wrote:

Curmudgeon wrote: I once saw a Kia Rio with 9,000 miles with a complaint of engine rattle. The oil had not been changed. The oil at the bottom of the pan looked like chocolate pudding, when the drain plug was removed you could see the stuff but it wouldn't come out.

1.6? I'm fairly sure this is the same engine. It's hard to compare an engine that spends most of its life at WOT because it's a small engine in a hyper-tall geared car, versus a large-engined car that barely loafs along, hardly strained at all.

That's the one. The fact that engine 1 (9k) survived being driven ~40 miles at highway speeds to the shop and engine 2 survived ~31k miles of being driven with the original oil and filter speaks to how tough the little things really are.

One of the last cars I saw before moving to my current employer was a 2002 Elantra, identical to mine (5-spd GLS) with 62k miles and a siezed engine. Got the car in on the lift, it had the oiginal black (back when they still came from Korea with the black oem filters) oil filter. Dropped the car down, checked the dipstick to find no oil. Popped the cam cover to find the cams completely hidden under sludge. That was were the tear down stopped. Customer came in to see what they found out and was shocked that the car needed an engine. When asked if she'd ever changed the oil, she looked at the advisor and said "I thought that was part of the warranty." When the oil light came on she would just "add a quart of oil". she kept adding it until the car was so sludged up that the oil pump could no longer suck anything through the mass of sludge in the pan.

62k miles. WTF? I realized right then that if I even changed the oil semi-regularly that the same engine in my car should run forever, even as I beat on it it's entire life. So far so good.

Official max distance oil change interval for normally aspirated Porsche is 15,000 miles. I wouldn't go that far, but it's factory approved.

Maybe that car with all the sludge in the sump spent a ton of time idling (like 6 hours every day)?

Circa 1989 had a Tempo come in the shop with a complaint of smoking when turning corners, ~42k on the car. The tech pulled the valve cover to check the oil separator to discover a solid lump of sludge in the shape of the valve cover. At the time, Ford painted the engines gray with the filter in place; it still had the OE filter, the oil had never been changed. Same as Bobzilla's situation, the customer just kept adding oil if the oil light came on.

He was pissed when we said the powertrain warranty would not cover it because the OE filter was still in place, he claimed that was because he bought filters from us (he had no receipts to back it up, also we sold Motorcrafts which were white) and when that didn't work he threatened to sue. His dad came down later to have his son's back and that's when I realized some people have horrible personal hygeine (but that's another story entirely).

There are so many variables which go into the life of engine oil that IMHO it's just a helluva gamble to run really long intervals.

Bobzilla wrote: I realized right then that if I even changed the oil semi-regularly that the same engine in my car should run forever, even as I beat on it it's entire life. So far so good.

I can't even go 2k in my VW before the lifters start clacking like castinets. Fresh oil and it clears right up.

I dunno how some people get away with things sometimes.

For years I ran my vehicles to one year, resulting in 8-9 K miles before I changed the oil. 75K on one , 72K on the other. Both ran better than new.

my brand new mazda 3 specifies synthetic AND 5000 mile intervals.

is that direct injection pump sheering the poo out of it or what?

belteshazzar wrote: my brand new mazda 3 specifies synthetic AND 5000 mile intervals. is that direct injection pump sheering the poo out of it or what?

Depends on where it's mounted. The one on my friend's Focus appears to be stuck on the end of one of the camshafts, like a Quad 4/Ecotec power steering pump. Most manufacturers put the pump on one of the valve covers, driven directly off of a three- or four-sided lobe on one of the camshafts.

I am assuming that yes, poo is bearing shorn away.

Another thing to consider is that engines with VVT and such can be very temperamental with respect to viscosity. Run the wrong grade oil in some VVTs and you'll find yourself setting cam position rationality codes. (It's programmed to know that X change in the solenoid should result in Y degrees change, if that is consistently off, then the computer assumes a problem, which in this case is correct) Anything with cylinder deactivation is also sensitive to oil viscosity.

They really want you to have oil that is the proper viscosity, no matter how old it is. So they also want it changed before it's likely that the viscosity will start breaking down.

GM's been having problems with cam wear again, in addition to the 3.6 timing chain issues... thus the new oil specs, and the reflashing of the computer to reduce oil change intervals to a maximum of 5k despite the special oil. The bulletin also states that, if the computer is ever reset between oil changes, to go 3 mo/3000mi from the previous change...

Knurled wrote:

Bobzilla wrote: I realized right then that if I even changed the oil semi-regularly that the same engine in my car should run forever, even as I beat on it it's entire life. So far so good.

I can't even go 2k in my VW before the lifters start clacking like castinets. Fresh oil and it clears right up. I dunno how some people get away with things sometimes.

Thats not the oils fault. I have a 10 valve 850 Volvo, which happens to share the lifter with the VW. 20 valve lifters are $20 each, and I've changed one set...10 valve lifters are $6 each...you can tell the rest of the story.

As an aside, the 10 valve cars were never imported into the states.