oil change ?

[lseguy]

And just to clarify. Under Federal Law, an ENTIRE warranty can't be voided..simply because a person didnt follow manufacturers service interval recommendations. A warranty claim can potentially be denied, however.

If I change my oil every 15k miles..and my starter goes bad..and Im still under warranty? They can't refuse to replace that starter. One has nothing to do with the other.

If I change my oil every 15k miles (keep in mind Im talking Lincoln LS..because BMW and Mercedes actually recommend 15k mile intervals with Synthetic oil) and I spin a bearing, and it's PROVEN that it was due to inadequate lubrication due to the oil/oil properties? Then that is a different story.

But as long as I can keep getting 120k miles plus with NO problem on 10k intervals? Chances of me going back to 3k...or even 5k, are slim to none.

 

[SoonerLS]

Why is it that every other vehicle (plane, truck, etc.) has its oil changed based on service time, not mileage. Why are cars generally based on mileage, when it seems to me that the time an engine has been running is a better indicator of when to change.

You got me. My tractors have engine hour counters instead of odometers, and they're supposed to have maintenance done based on hours of running time.

Maybe it's because cars and light trucks are the only ones whose running time can realistically be measured in thousands of miles: semis will go thousands of miles in a few days; tractors may not go a few thousand miles in years of usage; aircraft can go thousands of miles in a few hours. They also have the least predictable operating conditions; they can spend minutes in stop and go traffic, followed by hours of highway speed running--the other major vehicles are going to have more predictable, closer to steady-state operating conditions.

If you go with the higher-end oils (like Amsoil), they actually recommend changing it based on oil chemistry, not mileage. You're supposed to send in a sample of the oil periodically, and they tell you if it needs to be changed based on their anaylsis of its condition.

 

[Jim Henderson]

OH boy, pumping all the oil out by cranking the engine with the filter off etc, is probably one of those TV ads wanting to be made.

You want to minimize the time that your engine is not pumping oil. That is why many people pre fill their filters so that there is not that moment or two of dry cranking while the filter fills up. Also most engine rebuilders like to prime the oil system so that there is minimum dry crank time. They also put assembly lube on things to make sure the engine has some protection during that first few seconds of life when there is no oil pressure.

A dry engine is one that is putting on lots of wear for a few seconds. I think there was a study by one or more of the major manufacturers that pointed out that the majority of engine wear is not during driving, but during the few seconds of startup.

Please don't dry crank your engine. You really won't get much more out anyway. Once the oil pickup tube is out of the oil, the pump quickly loses it's prime and then you are pumping air. Air is a lousy engine lubricant. Also once in a great while, an oil pump can completely lose it's prime and then you won't have any oil pressure for a long time.

The little amount of dirty oil left in the engine won't hurt it, especially when diluted with what, 7 quarts of fresh oil?

Good Luck,

Jim Henderson