UOA - Longer change interval, LESS WEAR!!
10-06-2011, 11:15 AM
#16
Race Director
Macster:
My oil weight wasn't a typo, I am using 5W50 in my car. Certainly, if you are putting lots of miles on your car, a short oil change cycle can become a real pain in the neck, to say nothing of the added cost!!
I think, though, that if I was only putting 3K on my car in a year, I would change the oil more than once a year. Whatever happened to those 3 months or 3,000 miles thresholds?
larry
My oil weight wasn't a typo, I am using 5W50 in my car. Certainly, if you are putting lots of miles on your car, a short oil change cycle can become a real pain in the neck, to say nothing of the added cost!!
I think, though, that if I was only putting 3K on my car in a year, I would change the oil more than once a year. Whatever happened to those 3 months or 3,000 miles thresholds?
larry
Putting lots of miles on a car actually works to allow one so inclined to stretch out the oil change interval. In fact when I left the oil had some miles on it already, under a 1000 but not by much. So when I return home the oil will have over 5K miles, closer to 6K miles.
However, once I return home my usage of the vehicle reverts to less than constant on the road at high speed driving so the oil can load up with contaminates and gets exposed to higher temps -- from idling in stop/go traffic for instance -- which can really take a toll on the oil.
My memory is not what it used to be and I never used indy oil changers but 3 months or 3K miles oil changes seems like an oil changer's sales pitch.
To each his own but I'm comfortable with 5K mile oil/filter services given my usage and as I mentioned before if I didn't cover 5K miles per year I'd still change the oil every year, at least. I might even be inclined to change the oil even more often, but I simply can't imagine a scenario in which I'd not drive my Porsches more that that few miles per year, so I've never seriously taken the time to think about what I'd do in a low miles per year situation.
Sincerely,
Macster.
10-06-2011, 11:21 AM
#17
Race Director
FYI-
You should drive the car for 20-30 minutes at temp, and park it. Then change the oil. You can do it when warm or the next AM. (Purists will claim you need to drain it warm...whatever.)
This will ensure you don't have fuel from the cold start. (The rich running at start will elevate fuel in the oil, but then will evaporate once fully warm.)
A
You should drive the car for 20-30 minutes at temp, and park it. Then change the oil. You can do it when warm or the next AM. (Purists will claim you need to drain it warm...whatever.)
This will ensure you don't have fuel from the cold start. (The rich running at start will elevate fuel in the oil, but then will evaporate once fully warm.)
A
Then a specific amount of oil is to be added to the oil tank. All of this works to ensure an amount of oil is removed from the engine consistent with what is called for to be added to the engine to afterwards have the oil level at the right spot on the oil level display. The 7 lowest segments want to be lit, that is the oil level wants to be at the max line but not above.
Sincerely,
Macster.
10-06-2011, 01:11 PM
#18
Burning Brakes
Purists I don't know but the factory oil change procedures call out an oil temp (at least 70C maybe 80C -- my references are at the office -- say at least hot enough to check the oil level) before draining the oil followed by a 20 minute drain time.
Then a specific amount of oil is to be added to the oil tank. All of this works to ensure an amount of oil is removed from the engine consistent with what is called for to be added to the engine to afterwards have the oil level at the right spot on the oil level display. The 7 lowest segments want to be lit, that is the oil level wants to be at the max line but not above.
Sincerely,
Macster.
Then a specific amount of oil is to be added to the oil tank. All of this works to ensure an amount of oil is removed from the engine consistent with what is called for to be added to the engine to afterwards have the oil level at the right spot on the oil level display. The 7 lowest segments want to be lit, that is the oil level wants to be at the max line but not above.
Sincerely,
Macster.
My old Porsche I used to let it drain 22 minutes and that caused the motor to blow up.
But seriously, a few ounces of old oil, which has a perfectly acceptable TBN, mixed with the new fill- and the fill titrated to "full" on the dipstick, will make zero difference.
IMO
10-07-2011, 09:38 AM
#20
Race Director
Speak of the devil....
My old Porsche I used to let it drain 22 minutes and that caused the motor to blow up.
But seriously, a few ounces of old oil, which has a perfectly acceptable TBN, mixed with the new fill- and the fill titrated to "full" on the dipstick, will make zero difference.
IMO
My old Porsche I used to let it drain 22 minutes and that caused the motor to blow up.
But seriously, a few ounces of old oil, which has a perfectly acceptable TBN, mixed with the new fill- and the fill titrated to "full" on the dipstick, will make zero difference.
IMO
There are more than a few ounces of old oil left in the engine after a drain. There is probably nearly 2 quarts of oil still in the engine and one can't ever get that oil out.
But as I said that is not the issue. The issue is to consistently drain the same amount of oil from the engine so when the specified amount of oil is added this is used to verify the oil level sensor/sender is working properly.
Sincerely,
Macster.
10-07-2011, 09:51 AM
#21
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Larry, did you by chance do the Chevron Fuel System Cleaner (with Techron) prior to the oil change?
Here is my Blackston UOA report from a couple weeks ago on my 987S. Most recent oil used was Mobil 5W50, like you. Prior to that, almost all was Red Line 5W40.
Here is my Blackston UOA report from a couple weeks ago on my 987S. Most recent oil used was Mobil 5W50, like you. Prior to that, almost all was Red Line 5W40.
10-07-2011, 03:45 PM
#22
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I can't see how letting your oil drain for 22 minutes, 30 minutes or 10 minutes would affect how your engine runs. The key is that you fill it up to the requisite mark when you are done draining it. I had a 73 with a front fender oil cooler. The lines between the engine and the loop cooler were long and held another quart or two of oil. When I drained it for an oil change, there was no drainage of the loop cooler nor the lines. It really didn't matter that much. But I don't see that "how long it drains" would have any impact on the engine blowing up.
larry
10-07-2011, 04:49 PM
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10-08-2011, 10:41 AM
#27
I think with super high quality oil the longer interval is fine. My opinion....if you track, probably worth doing those miles by a multiplier....but frankly, a rev is a rev, so I am just not sure about that either. I drive with verve on the winding roads...while not a track session, these can last an hour or two...not 20 minutes.... The main data point for us is T2's car with frequent changes with 0w-40. There is nothing similar for a 5w-50 or 5w-40tdt car afaik. Kevin of UMW may have more to say.
I suspect even 7500 is fine with top end oil like 5w-50.
I run 5w-50, have changed at 5-6k intervals, and have had no issues. The car will outlast me at this point. And I am not that old.
What is the Porsche specific European interval these days, 20k kms?
JB
I suspect even 7500 is fine with top end oil like 5w-50.
I run 5w-50, have changed at 5-6k intervals, and have had no issues. The car will outlast me at this point. And I am not that old.
What is the Porsche specific European interval these days, 20k kms?
JB
10-08-2011, 11:07 AM
#28
Race Director
I think with super high quality oil the longer interval is fine. My opinion....if you track, probably worth doing those miles by a multiplier....but frankly, a rev is a rev, so I am just not sure about that either. I drive with verve on the winding roads...while not a track session, these can last an hour or two...not 20 minutes.... The main data point for us is T2's car with frequent changes with 0w-40. There is nothing similar for a 5w-50 or 5w-40tdt car afaik. Kevin of UMW may have more to say.
I suspect even 7500 is fine with top end oil like 5w-50.
I run 5w-50, have changed at 5-6k intervals, and have had no issues. The car will outlast me at this point. And I am not that old.
What is the Porsche specific European interval these days, 20k kms?
JB
I suspect even 7500 is fine with top end oil like 5w-50.
I run 5w-50, have changed at 5-6k intervals, and have had no issues. The car will outlast me at this point. And I am not that old.
What is the Porsche specific European interval these days, 20k kms?
JB
Driving usage has changed and not for the better. In many parts of the country drivers are spending more time in traffic, with the engine idling. Also, some studies have found drivers are traveling more miles due to various factors.
Then there are significant climate differences. Europe climate is for the most part milder (at least in the summer) than many many parts of the USA. 100+ F. highs are the norm for many locations in the south/south west (even midwest) during the hottest summer months. Has it every hit 100F in Germany?
Also, and this again was highlighted on this road trip, many areas of the USA are very very dusty. While the air filter does remove the larger particles of dust smaller particles make it past the filter. One assumes that the filter is designed so that any particles that make it through are too small to matter, but they do end up in the oil, some of them, where they are either captured by the oil filter or not. In either case they can only be removed from the engine by changing the oil and the filter.
An oil change interval is part religion, part science. The oil change intervals offered by car makers are somewhat optimistic, extended, due to a variety of factors. One is as soon as one car maker throws engine hygiene common sense out the window and starts specifying more miles between oil changes -- because its engines are made 'better' -- other car makers are almost forced to follow suit or sell cars against the rep its engines are *not* as good as other car makers because their engines require fewer oil changes.
My belief has always been I'll change the oil when I think it is due to be changed based on my driving style and regional weather conditions.
As I touched upon in other postings early on I had a UOA performed on my new Boxster's oil -- with about 4K miles on the oil -- and found considerable water build up. I was aware this could happen but believed I was doing the right things to keep this down. I was wrong. Wrong in that later investigation by me found that these engines (generally speaking) take a long while to warm up and even in cold weather can run quite cool, cool enough the oil doesn't get hot enough to boil out the water so even though I was not using the car for short trips, the car was seeing plenty of highway miles, this did not allow the oil to get hot enough. Hence the water buildup.
It was at this time I decided to follow a 5K mile oil/filter service schedule vs. the 15K oil/30K filter service schedule Porsche provided for.
Given where I live now -- CA -- I might be able to extend this some but I have to note temps where I live can get quite high. And the area is dusty. Plus there is always the traffic. On the freeway I'm either running at the speed limit or in stop/go traffic due to congestion.
So, I hit upon 5K miles oil change intervals and so far neither of my cars' engines exhibit any problems due to oiling problems, either from running the oil too long or from changing the oil too frequently.
Sincerely,
Macster.
10-08-2011, 12:39 PM
#29
Burning Brakes
Adam:
I can't see how letting your oil drain for 22 minutes, 30 minutes or 10 minutes would affect how your engine runs. The key is that you fill it up to the requisite mark when you are done draining it. I had a 73 with a front fender oil cooler. The lines between the engine and the loop cooler were long and held another quart or two of oil. When I drained it for an oil change, there was no drainage of the loop cooler nor the lines. It really didn't matter that much. But I don't see that "how long it drains" would have any impact on the engine blowing up.
larry
I can't see how letting your oil drain for 22 minutes, 30 minutes or 10 minutes would affect how your engine runs. The key is that you fill it up to the requisite mark when you are done draining it. I had a 73 with a front fender oil cooler. The lines between the engine and the loop cooler were long and held another quart or two of oil. When I drained it for an oil change, there was no drainage of the loop cooler nor the lines. It really didn't matter that much. But I don't see that "how long it drains" would have any impact on the engine blowing up.
larry
It's an 'oil thread' and you will get all the usual religious nonsense.... BUT, Kudo to you for basing YOUR decisions on YOUR own UOA based on how YOU drive YOUR car. Really. Well done, and thanks for posting.
All the other discussion of 'how I drive' and 'european climate' and Porsche recommendations is mental masturbation.
A