I said that cooling was out and fuel was out but valve wear and smog problems are oil related and has to do with type of oil and oci. It was top end wear that set them looking for a different oil. Notice I said different. I have no idea if the new oil is better. But looking through the data, valve train wear reparis were more expensive late in the cycle for the longer oci group. Is that statement confusing?
longer oci's
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Neat discussion LarryL. I use 2000 mile OC's. I know I am wasting money but I like a clean motor.
Dino Havoline 10W30 in summer and 5W30 in winter here is Manitoba, Canada.
Jim
CYWG
Dino Havoline 10W30 in summer and 5W30 in winter here is Manitoba, Canada.
Jim
CYWG
You might want to analyze the cost of syn vs. mineral, comparing only the extra valvetrain repair costs, and maybe emissions. Cooling system failures would probably be coincidental.
Another question to look at: When cooling systems failed, was there more damage to the cars on petroleum oils than those on synthetic oils?
Synthetic oil advertisements often claim better protection at extreme temperatures.
Hmm... you wrote, "Overall the synthetic oil cars were cheaper to maintain, including the ones that needed repair.", yet the management has decided to switch away from synthetic oils. Aren't they trying to minimize overall costs? Or maybe they'll switch to the synthetics from Chevron.
Another question to look at: When cooling systems failed, was there more damage to the cars on petroleum oils than those on synthetic oils?
Synthetic oil advertisements often claim better protection at extreme temperatures.
Hmm... you wrote, "Overall the synthetic oil cars were cheaper to maintain, including the ones that needed repair.", yet the management has decided to switch away from synthetic oils. Aren't they trying to minimize overall costs? Or maybe they'll switch to the synthetics from Chevron.
You might run a test.
Take a group of syn oil vehicles and bring them through the shop for an 'simulated oil change' at the same intervals as the dino oil vehicles.
Then you might be able to tell if the extra mechanic inspection times correlates with a lower incidence of cooling and valve train issues.
Take a group of syn oil vehicles and bring them through the shop for an 'simulated oil change' at the same intervals as the dino oil vehicles.
Then you might be able to tell if the extra mechanic inspection times correlates with a lower incidence of cooling and valve train issues.
Good idea. Since the unscheduled repairs occurred after 100,000 miles, maybe the cars should be put on synthetic, and after 100,000 miles start inspecting for cooling system problems (bad hoses, etc.) between oil changes.
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I am also curious to what specific types of repairs would be required in this type of service. The only type of repair realated to lubrication that I can think of would be something like a timing chain ..otherwise I'd term it somewhat "serious" in nature.
Tones, actually you have the right idea. The biggest problem was cooling system failure. These problems would stop a car and cause a lot of damage. Next were, late in the 100k cycle were dirveability problems that related to smog and fuel control/system problems. One problem found more often in the synthetic oil cars was top end wear and valve train noise, also only very late in the 100k cycle, though. One of the reasons for changing the brand of synthetic oil was the valve train wear.
I'm trying to get the data released so I can publish it in various formats. The problems is that this data is considered a business advantage, which it is. One piece of info is the use of Chevron oil. If it proves to be a good choice it will have survived many miles of testing against a half dozen other oils. The current test with 10 vehicles, Civics an Accords, is going well. Several cars on on a pace of 50k+ miles a year with heavy stop and go driving with the same drivers and a bit of extra monitoring. The software rates driving aginst tire wear and gas mileage with some cars having a tracking device that monitors speeds, brake use and engine starts/stops. Also remember all these vehicles are in the sun belt. The only weather problems for the overall fleet was the loss of 23 vehicles to two hurricanes.
I'm trying to get the data released so I can publish it in various formats. The problems is that this data is considered a business advantage, which it is. One piece of info is the use of Chevron oil. If it proves to be a good choice it will have survived many miles of testing against a half dozen other oils. The current test with 10 vehicles, Civics an Accords, is going well. Several cars on on a pace of 50k+ miles a year with heavy stop and go driving with the same drivers and a bit of extra monitoring. The software rates driving aginst tire wear and gas mileage with some cars having a tracking device that monitors speeds, brake use and engine starts/stops. Also remember all these vehicles are in the sun belt. The only weather problems for the overall fleet was the loss of 23 vehicles to two hurricanes.
I never said they were going to swith away from synthetic. Let me repeat. They use Chevron Supreme conventional and Mobil 1. They are dropping Mobil 1 for Chevron Supreme Synthetic. The conventional oil stays the same. This change is requested by the maintenance management and price is in this desicion somewhere, as always. From uoa's and repairs, they had complaints about valve train wear with Mobil 1, but, again, that's not to say that any other oil might have had the same problem, we don't know yet. And these valve train wear problems with synthetic were late in the third year or the forth year or 50-60k+ miles. If this pattern continues they are going to change more than the brand of oil, but right now they are testing and looking.
LarryL, I am wondering: (bear with me, please; I appreciate what you can answer)
Are we speaking of only repairs, or of repairs arising out of delayed maintenance? That is, unscheduled repairs at the end of the third year?
Are the vehicles all being maintained by the factory-recommended service intervals, both time and mileage? Or are they being observed in the breach? That is, are the longer OCI cars also less likely to be conscientious of time intervals on maintenance than are the shorter OCI vehicles? Are they being dealer-serviced, or is a contractor handling the work?
Do the schedules used by these customer fleets include non-book intervals, say, two years or 50m miles where a mechanic is going over the vehicles more carefully to ascertain condition to prevent problems?
Finally, if I missed it, do these two customers (branchs?) have related, or unrelated, responsibilities?. That is, is the longer OCI fleet comprised of full-commission salesmen idling long periods on the phone and in all sorts of traffic, and the other group one of consulting engineers on dedicated assignments with regular routes? . . that sort of thing. Is one group being recompensed for gasoline and the other operating on corporate credit card? Are loaners of equal type easily available to one group, but not the other?
In short, the difference in motivation and attitude.
What about climate and topography? Desert vs the Central Valley; etc.
I think making generalizations about longer versus shorter OCI is in need of more context.
I've been hoping to see this sort of info for three years here at BITOG, and am glad of any insights. Thanks for the time you've given in this!
Are we speaking of only repairs, or of repairs arising out of delayed maintenance? That is, unscheduled repairs at the end of the third year?
Are the vehicles all being maintained by the factory-recommended service intervals, both time and mileage? Or are they being observed in the breach? That is, are the longer OCI cars also less likely to be conscientious of time intervals on maintenance than are the shorter OCI vehicles? Are they being dealer-serviced, or is a contractor handling the work?
Do the schedules used by these customer fleets include non-book intervals, say, two years or 50m miles where a mechanic is going over the vehicles more carefully to ascertain condition to prevent problems?
Finally, if I missed it, do these two customers (branchs?) have related, or unrelated, responsibilities?. That is, is the longer OCI fleet comprised of full-commission salesmen idling long periods on the phone and in all sorts of traffic, and the other group one of consulting engineers on dedicated assignments with regular routes? . . that sort of thing. Is one group being recompensed for gasoline and the other operating on corporate credit card? Are loaners of equal type easily available to one group, but not the other?
In short, the difference in motivation and attitude.
What about climate and topography? Desert vs the Central Valley; etc.
I think making generalizations about longer versus shorter OCI is in need of more context.
I've been hoping to see this sort of info for three years here at BITOG, and am glad of any insights. Thanks for the time you've given in this!
I pulled out only cars in the sunbelt. I'm not smart enough to figure out much about cars in ice and snow. Crashes, salt damage and cold weather make things too dificult to figure out. Too many cars do not make it beyond two years. All drivers are watched and have yearly reviews which include gas/tire mileage, abuse and a carrot for being at least 'average' in maintenance costs and not getting tickets. Taking care of a car over a cycle, 4yr/100k miles results in more carrots. I do not know what they are, I just do the software but I do know people have received upgrades. If you are in a car the smallest thing can be a welcome upgrade.
It is rare that a failure can be tracked to missed maintenance, but it has happened. It is so rare that it is not representive of vehicle operation in general. There is little to learn form such an event except to say that routine maintenance is worth to trouble. Some failures that occur in a missed maintenance situration could have happened anyway. You're talking about something that will never get investigated. The problem will just get fixed.
The least a car is seen by a mechanic that knows the car is twice a year no matter what any other scheduled maintenance is. This is an important difference between some fleet maintenance, dealer maintenance, independent mechanic maintenance and quick lube. These fleets are mixed (synthetic or dyno) becuse corporate is trying to work out the best schedules, and the maintenance is more comprehensive than warranty required schedules. No matter what the factory recomends, certain things are done every 24 months, like coolant, transmission fluid flushes and p/s flush. Smog devices and plumbing are serviced more frequently, too. Cooling systems recieve a lot of attention, too, because they stop/destroy engines. Drivers are required to actually fillout check lists and turn them in with other paper work. Some of this is tied to the auto insurance. All cars are equipted with first aid kits, flares, a blanked and a tire pressure gauge and a big flash light, throw-away camera, accident report forms etc. All fuel is purchased with company cc's.
If vehicles don't have failures there are no major differences between Phoenix (hot, dry) and San Diego (perfect), west Texas( hot, dry, wide open spaces, high speed) or Texas gulf coast (hot, humid).
I'll try to get some more info based on your request. These guys like the software but think I ask too many questions. My main objective was to identify components that stop or damage a vehicle and built a curve that would tell me when they start becoming a problem. Example, a fan belt might last one hundred units of time. Up to eighty units there might be a one in 10,000 chance of a failure. After 80 units it might drop to one in 100 (not real figures, just an example). So you work out the maintanenace schedule to change it at or before 80 units. It is better to have your mechanic change it with your parts in your shop than to tow it it or have some mechanic that may have never seen your model car try the repair for the first time.
It is rare that a failure can be tracked to missed maintenance, but it has happened. It is so rare that it is not representive of vehicle operation in general. There is little to learn form such an event except to say that routine maintenance is worth to trouble. Some failures that occur in a missed maintenance situration could have happened anyway. You're talking about something that will never get investigated. The problem will just get fixed.
The least a car is seen by a mechanic that knows the car is twice a year no matter what any other scheduled maintenance is. This is an important difference between some fleet maintenance, dealer maintenance, independent mechanic maintenance and quick lube. These fleets are mixed (synthetic or dyno) becuse corporate is trying to work out the best schedules, and the maintenance is more comprehensive than warranty required schedules. No matter what the factory recomends, certain things are done every 24 months, like coolant, transmission fluid flushes and p/s flush. Smog devices and plumbing are serviced more frequently, too. Cooling systems recieve a lot of attention, too, because they stop/destroy engines. Drivers are required to actually fillout check lists and turn them in with other paper work. Some of this is tied to the auto insurance. All cars are equipted with first aid kits, flares, a blanked and a tire pressure gauge and a big flash light, throw-away camera, accident report forms etc. All fuel is purchased with company cc's.
If vehicles don't have failures there are no major differences between Phoenix (hot, dry) and San Diego (perfect), west Texas( hot, dry, wide open spaces, high speed) or Texas gulf coast (hot, humid).
I'll try to get some more info based on your request. These guys like the software but think I ask too many questions. My main objective was to identify components that stop or damage a vehicle and built a curve that would tell me when they start becoming a problem. Example, a fan belt might last one hundred units of time. Up to eighty units there might be a one in 10,000 chance of a failure. After 80 units it might drop to one in 100 (not real figures, just an example). So you work out the maintanenace schedule to change it at or before 80 units. It is better to have your mechanic change it with your parts in your shop than to tow it it or have some mechanic that may have never seen your model car try the repair for the first time.
I gave you the mix for the combined group and it only varies a few points in any group re-divided between oil types, not enough to make any difference.
For example the actual split for synthetic Hondas is 42% of the synthetic fleet vs 39% of the conventional fleet for Hondas, and the conventional Hondas had about 5% more mileage. I think the numbers for car count and mileage matches pretty well, because cars are pulled right on the button, mileage wise. 80% of the cars hit the mileage between 45th and 48th month. 15% hit the four years first with an average of less than 11k miles left to go. 5% are pulled for maintenance problems, crashes, changes in use, transfers, or other problems. The 5% changes but not too much.
Cars that did not follow the mileage/time pattern were jut not picked.
For example the actual split for synthetic Hondas is 42% of the synthetic fleet vs 39% of the conventional fleet for Hondas, and the conventional Hondas had about 5% more mileage. I think the numbers for car count and mileage matches pretty well, because cars are pulled right on the button, mileage wise. 80% of the cars hit the mileage between 45th and 48th month. 15% hit the four years first with an average of less than 11k miles left to go. 5% are pulled for maintenance problems, crashes, changes in use, transfers, or other problems. The 5% changes but not too much.
Cars that did not follow the mileage/time pattern were jut not picked.
ok. but think you can see why I asked.
as was alluded to earlier, the longer OCI units may not get the top-off that appears to be a common need on longer OCIs, those with more frequent OCI are less likely to run low ever.
regardless, we have a lot of extraneous data here, like the potential change from one brand to another within the synthetic group. It doesn't matter and needs to be ignored. (I think you are, LarryL but not every one seems to be getting that point...)
So.... we have 2 almost identical groups consisting of approximately equal mix of makers and engines with fairly similar tho not identical drive patterns in a wide range of geographies.
Group 1 is 3-5k OCI/dino and group 2 is extended/synthetic. Your tossing the data from the cars outside the mileage or other mixes is just fine, no issues there at all.
What other pertinent variables are there that I may be missing here?
as was alluded to earlier, the longer OCI units may not get the top-off that appears to be a common need on longer OCIs, those with more frequent OCI are less likely to run low ever.
regardless, we have a lot of extraneous data here, like the potential change from one brand to another within the synthetic group. It doesn't matter and needs to be ignored. (I think you are, LarryL but not every one seems to be getting that point...)
So.... we have 2 almost identical groups consisting of approximately equal mix of makers and engines with fairly similar tho not identical drive patterns in a wide range of geographies.
Group 1 is 3-5k OCI/dino and group 2 is extended/synthetic. Your tossing the data from the cars outside the mileage or other mixes is just fine, no issues there at all.
What other pertinent variables are there that I may be missing here?
12k OCI on average for the synthetics ? That seems to be pushing it unless the vehicles were developed to use such an interval. In general vehicles in Europe seem to use longer OCIs, but it's also typically with heavier oils.
I think that 'oil related failures' would also have to include sludge and varnish, considering the oil breather, PCV, and to a lesser extent the EGR systems on most vehicles these days.
I think that 'oil related failures' would also have to include sludge and varnish, considering the oil breather, PCV, and to a lesser extent the EGR systems on most vehicles these days.
The drivers have a weekly check list. Experience with tires proves they are at least keeping the tires inflated. In this group there are few tire failures that are not connected to running over stuff. They have hazard coverage on all tires and that lets us know whats happening. And they have makeup oil in off all things the first-aid/safety kit, along with gloves for some and some rags. The weekly check list should catch the oil level. A lot of people do their own check list. Some have a shop do it, but that number is going down. It's not dificult. It's been discovered that males can learn how to do the list, too.
There was one incident that saved the driver some trouble by doing the check list. She squeezed the top radiator hose and it just came off the radiator. Somehow it stayed on for her first drive from the shop, but came off the next morning. The technical term (the polite one) for this failure is 'Oops!'.
There was one incident that saved the driver some trouble by doing the check list. She squeezed the top radiator hose and it just came off the radiator. Somehow it stayed on for her first drive from the shop, but came off the next morning. The technical term (the polite one) for this failure is 'Oops!'.
Thanks for the context and more detail, LarryL.
This is a good topic.
This is a good topic.
My hypothesis is that the vehicles with longer OCIs aren't having the oil level maintained as well as the shorter OCI vehicles. Thus, with a little oil use and/or shearing/thickening out of grade, the longer OCI vehicles are spending more time running an out-of-spec oil or oil level, leading to increased valve train wear.
The vehicle spread is about 40% Honda sedan, 40% Toyota, 10% Ford and Chevy and 10% Nissan and Chrysler/Dodge. The misc brands are being dropped, partially because of the economics of fleet purchasing. Other vehicles were included in the group becuase of small percentages. These other cars may be good vehicles, but I don't know, one way or the other.
I may be able to get permission to publish data up to 2003, after the first of next year but I'm not sure. I'm pressing to get it all because there have been a lot of changes, since 2003.
The stuff I'm talking about is included in the previously posed dates.
I may be able to get permission to publish data up to 2003, after the first of next year but I'm not sure. I'm pressing to get it all because there have been a lot of changes, since 2003.
The stuff I'm talking about is included in the previously posed dates.
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