This is why I tell people not to change oil at 15,000 miles...

[M. Sage]

I had two jobs where we tested lubricants and their role in keeping mechanical devices running. Maybe what I learned will be helpful.

The first job was at big Vickers/Sperry Rand gear products division in Tulsa. We ran transmissions and gear boxes on a dyno to destruction. Temperature of the lubricant was the critical factor. A transmission under heavy, measured, load was run while temperature was maintained. The temp was raised higher and higher as the gearbox ran. Periodically, we would check wear on the gears and bearings. Day after day, the transmissions ran until we raised the temp another 10 degrees and the gears cratered. The gearbox would run perfectly until we hit that breakdown point of the oil then the box was destroyed! As little as 10 degrees made the difference in running well or complete destruction! Temperature of the lube was absolutely critical!

In the second job, I worked for McDonnell Douglas aircraft and maintained ground support equipment for military and commercial jet aircraft. Ground support equipment (GSE) has hydraulic systems built into the unit so the aircraft systems can be function tested while the bird is on the ground. Aircraft folks are FANATICS about about keeping GSE clean as hooking a dirty unit into a clean aircraft system trashes the aircraft system.

We took samples of the oil for lab analysis of viscosity, particle count and acid number. The particle count analysis was so strict that if you TOUCHED the open sample bottle neck with your finger, the sample would fail. If a sample failed, we re-sampled. If it failed again, the huge banks of filters were changed, system circulated then re-sampled. The filter banks had up to 35 6"x18" cartridge filters in each bank with up to 3 banks in each unit.

If the sample failed again, all oil was dumped, another filter change, flushing and a period of running to recirculate. Cleaning one of those GSE units was a HUGE expense but compared to trashing a $30 million aircraft, it was a bargain. At the time, Mil-H-5606 red oil for the military jets cost $8/gallon and the Skydrol and Hijet synthetic oil cost $36/gallon. We dumped hundreds of gallons of oil! God only knows what the filter banks cost to restore.

Summed up, my experience taught me:
The biggest factor in having oil do its job in keeping a machine running is temperature. If temperature is kept to acceptable limits, how much crap you put INTO the oil determines how long the oil can be safely run.

With the car shown above, I'd say water was getting into the oil either from the combustion process or a coolant leak. Someone suggested sabotage. It has happened before. Either way, that car is toast.

Flash

That's interesting stuff, and I agree with you on what kills oil. Particulate can usually be filtered out (newer filters are very good), but temperature is crucial. I also agree a lot that conditions are what matter most in determining how long you can run the oil. If I was driving out to El Paso and back every day, then yeah I'd be fine changing my oil every 15,000 miles. But for your typical driver? No way.

A switch to a run hours interval would be great. I've thought several times about putting an hour meter on my own car for that reason alone. If you're running 70 miles an hour, you're going to do as many miles in about four hours as I do in a typical work week. So mileage is really one of the worst ways to determine if oil should be changed, but we can't get away from it for some stupid reason, even in the age of computerized-everything on cars.

This wasn't water contamination, though. That looks like a milkshake since being pumped through the engine emulsifies the water into the oil.

I run the oil in my BMW 12-15k (depending on what the on board computer tells me) and I have never see anything like this.

At work we have pictures of this happening in BMWs, too.

Let me put it this way - we don't make money off oil changes. Techs get paid a half hour to test drive a car, pull it in, do an inspection, change the oil (which is getting tougher and tougher to do with all this plastic on the bottom of cars), inflate tires etc. and test drive again. I know I don't make money changing oil, and I know the shop doesn't either. But we suggest 6,000 mile oil changes, and suggest that new BMW owners change the oil on their dime in between scheduled changes.

Much discussion on the Volvo boards re: Euro marques recommending 15K miles between changes of FULL SYNTHETIC oil. Volvo uses a syn-blend here in the States and recommends 7500 miles for oil change intervals. It's quite interesting when the dino-guys and the syn-guys go at it . Back in the old days, I was a 3000 mile oil change nut...even when I didn't have the money in my pocket. I've never had an oil-related engine failure--going as far back as my 1960 Stude Lark VIII. I stick with the factory recommendations of 7500 miles now...I'm not ready for 15K miles! Rancher B-I-L has over 350K miles on his F ?350? dually. I reckon diesels have different requirements, but 350K miles of dusty hot Texas workin' sounds pretty good to me!

Synthetic is the only way to go these days. But it will still sludge up if you run it too long. Engines are going up in specific power and down in emissions. They're becoming severely over-stressed with everything that's being asked of them, and something has to give somewhere.

The main reason I see for the uber-high mileage changeout with BMW and a lot of other Euro brands is their free maintenance programs. They're trying to cheap out. There is also environmentalist pressure to cut down on used oil. BMW caved to the greentards quite some time ago; word in the industry is that recycled plastics are the reason that their cooling systems break so much.

And yeah, diesels are different. Diesel trucks have huge oil capacities for one thing. For another, I don't think they're seeing nearly as high combustion temperatures as these gasoline engines.

 

[Dcav]

Feel lucky our techs get .3 to change oil.

 

[coachrick]

The main reason I see for the uber-high mileage changeout with BMW and a lot of other Euro brands is their free maintenance programs. They're trying to cheap out. There is also environmentalist pressure to cut down on used oil. BMW caved to the greentards quite some time ago; word in the industry is that recycled plastics are the reason that their cooling systems break so much.

My last two Volvos have included free maintenance (36k miles and 60k miles), so I'm on my dime on the earlier one.(45K miles on '10 XC60 T6). Volvo is sticking with the 7500 mile intervals(using syn-blend Castrol). I'm tempted to go full synthetic on the older vehicle and 7500 miles seems reasonable. It just 'feels' right to change oil after enduring the heat of summer(all FIVE months of it!) and then again just before the next heat wave...so--spring and fall services @ ~ 7500 miles for us.

As long as we're under the hood, any thoughts on K&N type 'permanent' filters for air intake? or anything other than 'factory' filters for the oil?

Thanks for the enlightening discussion!

 

[M. Sage]

As long as we're under the hood, any thoughts on K&N type 'permanent' filters for air intake? or anything other than 'factory' filters for the oil?

Thanks for the enlightening discussion!

The K&N filters are worse than standard filters.

The oiled-type K&N will shed oil when they're new (or freshly-cleaned) and don't filter as well. You probably won't notice any gain in performance, and you definitely won't notice any gain in mileage, even if it wasn't coating your air flow sensor with dirt and oil (which causes the air flow sensor to read higher, making the computer assume there's more air going into the engine... If you let it get bad enough, you wind up rich at light loads and lean at high loads). I ran one years ago in my Miata, but kept having to clean the dirt off the MAF. I threw the K&N in the trash and went back to paper. No loss in performance, no loss in mileage, and no more cleaning a delicate sensor regularly. In everything except wide-open, high RPM driving, you will never notice a difference between a high-flow filter or even a very dirty filter vs new OE style. At most part-throttle cruise, the engine isn't going to need nearly as much air. Even if there is a bit of restriction in the air box, the driver is just going to crack the throttle open a bit more and the computer is going to keep the air:fuel ratio constant. The manifold pressure on a gasoline engine is not going to change at a part load due to a dirty or restrictive filter. I might dog on automotive engineers, but at least they're good about making sure an intake system can flow enough to feed the engine. So don't worry about the stock air box and stock style filter. They flow more than enough for 99% of the driving you do.

Before people start trying to tell me that a dirty filter will lower mileage because something like the mixture going rich because of the throttle being open wider... There's a reason that fuel injected cars get better mileage at higher altitudes. The throttle is open further for the same load and output, lowering manifold vacuum. And the computer accounts for the lower amount of air going into the engine, keeping the air:fuel ratio correct. These aren't carbureted engines...

Aftermarket oil filters... depends on the brand. We usually buy filters built by the OE supplier. Cheaper aftermarket filters are not as good, especially in European applications. Euros have generally gone to a "fleece" media over paper, and I've seen several of the paper media filters literally fall apart inside the car. I haven't seen one take an engine out yet, but I wouldn't be surprised if it's happened. Other problems I've run into with cheap aftermarket filters for Euro cars is that they might not include the o-ring(s) to reseal the filter cap. I've seen more than a few cars come in with oil leaks that were solved with an OE filter kit.

 

[Texas1911]

My last two Volvos have included free maintenance (36k miles and 60k miles), so I'm on my dime on the earlier one.(45K miles on '10 XC60 T6). Volvo is sticking with the 7500 mile intervals(using syn-blend Castrol). I'm tempted to go full synthetic on the older vehicle and 7500 miles seems reasonable. It just 'feels' right to change oil after enduring the heat of summer(all FIVE months of it!) and then again just before the next heat wave...so--spring and fall services @ ~ 7500 miles for us.

As long as we're under the hood, any thoughts on K&N type 'permanent' filters for air intake? or anything other than 'factory' filters for the oil?

Thanks for the enlightening discussion!

Modern OEMs have gone to really watching how much pumping losses the engine is encountering. As such things like air filters, catalysts, etc. no longer give the massive gains you saw in the 80s and 90s. Your average pleated air filter in an OEM vehicle flows probably two times what the engine is pulling at full load, so there's little in the way of pressure loss, especially at cruising speeds where you encounter low mass flow (and your resulting MPG).

Mike also mentioned the MAF issue with K&Ns.

OEM oil filters get a big +1 from me ... they are almost always the best on the market for the car. Wix builds a decent OE filter if you are in a pinch, but the lack of proper anti-drain back and media in most OE filters leaves something to be desired.

 

[Texan2]

I have done 20k oil changes on my personal vehicles for years using Amsoil/Amsoil filter, (I usually keep them to around 100k). Our PD fleet does the same as does Texas DPS fleet. No oil related failures. We had a guy go off road in a patrol car awhile back and the car ended up needing lots of work including a new oil pan. When it was apart (around 80k miles), I looked and you couldnt tell it from any car that had 3k oil changes.

Granted these are American cars with American V8s, not euro cars. I wouldnt try 20k oil changes with anything but Amsoil

 

[M. Sage]

Modern OEMs have gone to really watching how much pumping losses the engine is encountering. As such things like air filters, catalysts, etc. no longer give the massive gains you saw in the 80s and 90s. Your average pleated air filter in an OEM vehicle flows probably two times what the engine is pulling at full load, so there's little in the way of pressure loss, especially at cruising speeds where you encounter low mass flow (and your resulting MPG).

Mike also mentioned the MAF issue with K&Ns.

OEM oil filters get a big +1 from me ... they are almost always the best on the market for the car. Wix builds a decent OE filter if you are in a pinch, but the lack of proper anti-drain back and media in most OE filters leaves something to be desired.

+1 to all that. They're working so hard to wring the most power and economy out of their engines that trying to make the car breathe better is usually a losing proposition.

Wix does make some good aftermarket filters. Last time I checked, they made the filters for Napa. Fram filters are total crap... Bad anti drain back, inferior materials, bypass valves that don't work right...

 

[ROGER4314]

What works in a vehicle fleet doesn't always work in personal vehicles. A case in point is when I worked for Oklahoma State University. I had several fleet cars and took them to the far reaches (meaning boondocks) of the state to work with new teachers. I also went into the prison lockups to work with their teachers and they were usually in BFE, too. Every time I took the cars in for service, the front tires came back with 15-20 psi of air in them. It made the cars handle like crap so I inflated them to specs as shown on the door label.

I finally asked the shop boss why they did that and the answer surprised me. They were willing to take a hit on fuel mileage and tire life because properly inflated tires shook the front ends out of the cars. Of course, some years later, we had tires exploding over the same underinflation issues. I kept airing them up properly and it saved my life!

Going north on I-35 near Norman, a dumb Bxtch STOPPED IN THE MIDDLE OF THE EXPRESSWAY to check on a stalled car! I came over a rise, she was directly in front of me and I had zero time to even check my mirror. I yanked the wheel to the right and just missed her! Luckily, there was no car on my right. Had those tires been soft, the car never would have made that emergency, crazy lane change. That was the closest event I ever had and I knew I was a lucky SOB!

So....once again, what goes on in fleet operations may be real out of line for a personal vehicle. I would NEVER run my tires that soft yet OSU did that on all of their fleet cars.

Flash

 

[hkusp1]

That's bad mmkay.

 

[M. Sage]

What works in a vehicle fleet doesn't always work in personal vehicles. A case in point is when I worked for Oklahoma State University. I had several fleet cars and took them to the far reaches (meaning boondocks) of the state to work with new teachers. I also went into the prison lockups to work with their teachers and they were usually in BFE, too. Every time I took the cars in for service, the front tires came back with 15-20 psi of air in them. It made the cars handle like crap so I inflated them to specs as shown on the door label.

I finally asked the shop boss why they did that and the answer surprised me. They were willing to take a hit on fuel mileage and tire life because properly inflated tires shook the front ends out of the cars. Of course, some years later, we had tires exploding over the same underinflation issues. I kept airing them up properly and it saved my life!

Going north on I-35 near Norman, a dumb Bxtch STOPPED IN THE MIDDLE OF THE EXPRESSWAY to check on a stalled car! I came over a rise, she was directly in front of me and I had zero time to even check my mirror. I yanked the wheel to the right and just missed her! Luckily, there was no car on my right. Had those tires been soft, the car never would have made that emergency, crazy lane change. That was the closest event I ever had and I knew I was a lucky SOB!

So....once again, what goes on in fleet operations may be real out of line for a personal vehicle. I would NEVER run my tires that soft yet OSU did that on all of their fleet cars.

Flash

When you're driving long distances instead of shorter "normal" trips, you can rely more on the tires getting hot and staying that way to keep the inflation pressure up, too.

 

[winchster]

I have done 20k oil changes on my personal vehicles for years using Amsoil/Amsoil filter, (I usually keep them to around 100k). Our PD fleet does the same as does Texas DPS fleet. No oil related failures. We had a guy go off road in a patrol car awhile back and the car ended up needing lots of work including a new oil pan. When it was apart (around 80k miles), I looked and you couldnt tell it from any car that had 3k oil changes.

Granted these are American cars with American V8s, not euro cars. I wouldnt try 20k oil changes with anything but Amsoil

+1, my dad changed the oil in my moms car 2x a year for as long as I remember. She drove around 40k a year in west texas.

 

[Texan2]

automotive forums have insane threads where people do battle over the subject of sythetic/extended oil changes. LMAO....they are sometimes entertaining.

 

[shortround]

Click and Clack don't like Audi & VW because of oil problems.

I don't like either because they are not built here, and have gone down hill engineering wise for several years now.

Be well.

 

[M. Sage]

automotive forums have insane threads where people do battle over the subject of sythetic/extended oil changes. LMAO....they are sometimes entertaining.

Automotive forums are really hit or miss. I usually avoid them for anything but researching pattern failures. There is a little bit of good info but a lot of conjecture and plain bad info...

 

[SC-Texas]

I change mine every 4k now.

 

[Texan2]

Automotive forums are really hit or miss. I usually avoid them for anything but researching pattern failures. There is a little bit of good info but a lot of conjecture and plain bad info...

i have used them to ask about finding parts before and general automotive chat. funny to watch people argue over brand, be it automotive brand or oil brand.

 

[Rangerscott]

Ive been using Rotella T5 in my rebuilt vehicle engine (less than 25k) since I rebuilt it and Rotella T6 in my '01 Honda VFR (53,xxx) and my '09 Kawasaki ER-6N (4,xxx) with no problems. All get Purolator Gold filters. I tend to forget to write down the mileage so I change the oil when the oil is a certain darkness which is usually under 4k.

Advance usually does a deal 3 for $15 on the filters.

 

[Texas1911]

+1 to all that. They're working so hard to wring the most power and economy out of their engines that trying to make the car breathe better is usually a losing proposition.

My STI will barely engine brake ... granted it's got some inertia, but with an AWD drivetrain and a turbo providing backpressure you'd think it'd slow down, but it's only rocking 8:1 compression, LOL.

 

[Texastransplant]

Rented a new Impala for a 2500 mile roundtrip. It had 17k on it and I check the oil anyway even if NOT my car. The Change engine oil light was on, I went back inside and told them, they said it was fine. Well got it home and two quarts down which still didn't quite fill it up. Called again told them what I had done and he said thanks but that was it. Took the trip but I'd sure not want to buy that used rental car, are they all that bad? Perhaps, once looked to buy a 1 year old mustang from Hawaii. Looked under it and the underside was covered with rust and from living in the rust belt, well it was worse then a 3 year old car. By the way when the Impala change oil light is on, you can't read the odometer. Made it a pain to keep turning the key and in about 1 milla seconds get that mileage reading for the trip.

 

[jeepinbanditrider]

On my Saturn all you had to do was hit the trip reset post one time and it would switch back over to mileage. But it would go back everytime you restarted the car. After the light or warning comes on you have 600 miles according to the manual.

The last car I rented was a NIssian Versa. Only had 35k on the clock. Vibrated at highway speeds, the insturments were glazed over by some one using improper cleaning stuff and it pulled to the right. I would have taken it back but before I noticed the pulling right, vibration and dancing about at highway speeds I had already made it across Jacksonville close to the base and it was close to 9pm. Said screw it and just keep it for the few days I was there for a school.