Thoughts on partial oil changes?
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Thoughts on partial oil changes?
Whew!! I just completed my first oil change on my 993 C4S. (yes - I've had it changed many times before - I just never did it myself. Very rewarding feeling).
Anyway - it took me about 3 hours, which included going to get an oil filter wrench. I absolutely could not remove the 2nd oil filter without a wrench. I think I could do the whole task in 60-90 minutes the 2nd time.
Here's my question: you can drain about 8 of the 10.5 quarts of oil by simply removing the little access panel in front of the rear passenger wheel.
For low annual mileage, non-raced cars, is it ever acceptable to simply drain 8 quarts of oil without changing both filters and draining all 10 1/2 quarts of oil?
For example, I'm only putting about 2800 miles a year on my car right now. Certainly the filters aren't "used up" in that amount of time? Certainly the oil isn't used up either. However, due to moisture, etc, I understand you don't want to leave the same oil in your car for 2-3 years.
Can I just drain most of the oil perhaps every other time? I could do that in about 5 minutes.
What is the generally accepted practice?
Thanks!
Anyway - it took me about 3 hours, which included going to get an oil filter wrench. I absolutely could not remove the 2nd oil filter without a wrench. I think I could do the whole task in 60-90 minutes the 2nd time.
Here's my question: you can drain about 8 of the 10.5 quarts of oil by simply removing the little access panel in front of the rear passenger wheel.
For low annual mileage, non-raced cars, is it ever acceptable to simply drain 8 quarts of oil without changing both filters and draining all 10 1/2 quarts of oil?
For example, I'm only putting about 2800 miles a year on my car right now. Certainly the filters aren't "used up" in that amount of time? Certainly the oil isn't used up either. However, due to moisture, etc, I understand you don't want to leave the same oil in your car for 2-3 years.
Can I just drain most of the oil perhaps every other time? I could do that in about 5 minutes.
What is the generally accepted practice?
Thanks!
Seared
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From: Ellicott City, MD
I guess you could do that, but why would you?
I've changed mine twice since buying the car and admit that it's a long process. But you also know it's done correctly. I probably do between 3,000 and 6,000 miles per year.
Andreas
I've changed mine twice since buying the car and admit that it's a long process. But you also know it's done correctly. I probably do between 3,000 and 6,000 miles per year.
Andreas
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I guess I'm just wondering why Porsche made it possible to replace 8 quarts of oil in about 5 minutes? I think the owners manual suggests changing the oil filters only every other time.
When I just changed my oil, it still looked virtually new - still clear on my fingers rather than black. Heck - I don't know. Seems like I just wasted two perfectly good oil filters.
I'm not concerned about saving $30 for filters though.
When I just changed my oil, it still looked virtually new - still clear on my fingers rather than black. Heck - I don't know. Seems like I just wasted two perfectly good oil filters.
I'm not concerned about saving $30 for filters though.
Three Wheelin'
Joined: Oct 2006
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From: Tampa, FL
Hey, not a bad idea for such a low annual mileage car. you keep your additive package fresh. Not sure how changing the filters every other time would hurt with such little mileage. But you know you could get another quart or two out during your changes in a couple minutes by pulling the crankcase plug since the engine drains a bunch back there after shutoff. There is a pic of the plug on the p-car site.
http://p-car.com/diy/changeoil/
One warning would be not to pull the oil pressure relief plug since I've seen a bunch of posts on that. I have only changed my oil once in my 993 and I am not sure where that is.
http://p-car.com/diy/changeoil/
One warning would be not to pull the oil pressure relief plug since I've seen a bunch of posts on that. I have only changed my oil once in my 993 and I am not sure where that is.
Instructor
Joined: Apr 2007
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From: Taiwan
You might not want to DIY if you were living in Taiwan....
* 3 cans of Mobile 1 5w-50 one-gal at COSTCO, Taipei = US$23 x 3 = US$69
* 2 oil filters at DJ Motor 911, Taipei = US$25 x 2 = US$50 (made in Germany, good stuff)
* K&N air filter washed clean by DJ Motor, full SOP checks on brake fluid, ATF, tires, lights etc.
* Total labor cost at DJ Motor 911 = US$33
Above total = US$152
* 3 cans of Mobile 1 5w-50 one-gal at COSTCO, Taipei = US$23 x 3 = US$69
* 2 oil filters at DJ Motor 911, Taipei = US$25 x 2 = US$50 (made in Germany, good stuff)
* K&N air filter washed clean by DJ Motor, full SOP checks on brake fluid, ATF, tires, lights etc.
* Total labor cost at DJ Motor 911 = US$33
Above total = US$152
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From: South Florida
I think you need to look at it as a birthday present for your 993 and just do it every year, completely.
Save the old oil and use it in your SUV!
Sam's Club here in South Florida is selling Mobil 1 for $29.50 a Six Pack!
That's lower than it was 10 years ago!
Chris
Save the old oil and use it in your SUV!
Sam's Club here in South Florida is selling Mobil 1 for $29.50 a Six Pack!
That's lower than it was 10 years ago!
Chris
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Weathergirl
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Not to get all rational or anything, but it's pretty easy to figure out how well your oil is lasting. An oil analysis will tell you both how much of the additives are left and how well your filters are doing their job. It will also tell you how the base oil is holding up.
Changing your oil and filters too often is a waste of both time and money. It's very possible that your filters have plenty of life left in them, but your oil is worn out, in which case, a quick drain and refill makes perfect sense.
Changing your oil and filters too often is a waste of both time and money. It's very possible that your filters have plenty of life left in them, but your oil is worn out, in which case, a quick drain and refill makes perfect sense.
Drifting
Joined: Jul 2001
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From: St. Louis
Harvey,
How much on your cab? I need to move my 91 Targa first though.
Also what are the dates of the '08 Parade? I will be making my first vacation picks for 2008 soon and wnat to block that time frame. (2 weeks for me to match one week of my wife's time - I have odd days off)
How much on your cab? I need to move my 91 Targa first though.
Also what are the dates of the '08 Parade? I will be making my first vacation picks for 2008 soon and wnat to block that time frame. (2 weeks for me to match one week of my wife's time - I have odd days off)
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From: NE Florida
Originally Posted by C4S4ME
I guess I'm just wondering why Porsche made it possible to replace 8 quarts of oil in about 5 minutes? I think the owners manual suggests changing the oil filters only every other time.
When I just changed my oil, it still looked virtually new - still clear on my fingers rather than black. Heck - I don't know. Seems like I just wasted two perfectly good oil filters.
I'm not concerned about saving $30 for filters though.
When I just changed my oil, it still looked virtually new - still clear on my fingers rather than black. Heck - I don't know. Seems like I just wasted two perfectly good oil filters.
I'm not concerned about saving $30 for filters though.
I think a lot of us have problems getting past the ""3 mos. or 3,000 mi." frame of mind from the past. That was good for the oil cos. (and Jiffy Lube shops) but is overkill and wasteful. Understand I'm talking about full synthetic oil, not full dino oil.
Keep in mind, I'm NOT talking about cars that get tracked, that's another situation entirely.
I do take issue w/ BMW's current service schedule of every 15 - 20k (whenever the service light comes on), I think that is far too long between changes.
JMHO, TIFWIW, YMMV, DHMBIB ect.
Drifting
Joined: Aug 2005
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From: San Diego, CA
I'm always amazed at the logic of trying to save a small amount of money on an uber important low cost service when the car really deserves better and a full rebuild is in the neighborhood of 15K.
I have a full change with both filters done (at a cost of $180.00) every year even with only a 5000mi per yr avg., that's only $15.00 per month for the peace of mind it brings me, which in my book is a great value.
ZP44
I have a full change with both filters done (at a cost of $180.00) every year even with only a 5000mi per yr avg., that's only $15.00 per month for the peace of mind it brings me, which in my book is a great value.
ZP44
Weathergirl
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the peace of mind it brings me, which in my book is a great value
Drifting
Joined: Aug 2005
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From: San Diego, CA
Originally Posted by RallyJon
Just so you know what you're really paying for, can't disagree. We do a lot of things for our cars just because it makes us feel better. All cars seem to run smoother right after an oil change, so it must have been time, right?
I have been in love with this exact car since I drove it when it was brand spankin' new in 1995 at a PCA Performance driving school when it belonged to the original owner (my student).
Now that I'm the second owner and have my dream car, seems normal for me to lavish expensive care on what I obsessed on for over 10 years.
ZP44
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Dissenting opinion alert!!!
Given the mileage you stated, I think it's fine to simply change oil ...but do it right! Were I you, I'd swap out my Mobil1 yearly, but definitely change the large oil filter. The simple reason is that it takes no more than another 5 minutes to do if you're already draining oil from the tank plug. It's too cheap and easy to replace and not worth avoiding, IMHO.
I'd feel completely fine leaving the small oil filter in there and replace that, say, every other year ...putting you at what, 6K mile change interval?!! Factory recommends 15K on the large filter, 30K on the small. While I wouldn't go that long, I think you're well within that parameter
FWIW, I put maybe 10K miles/year on my 993. I change oil (Mobil1) every 7-8K along with the main (large) filter, and replace the small filter every other change ...again, that's a 15K interval where the factory recommends 30K so I feel very comfortable that I'm still overmaintaining my baby.
Given the mileage you stated, I think it's fine to simply change oil ...but do it right! Were I you, I'd swap out my Mobil1 yearly, but definitely change the large oil filter. The simple reason is that it takes no more than another 5 minutes to do if you're already draining oil from the tank plug. It's too cheap and easy to replace and not worth avoiding, IMHO.
I'd feel completely fine leaving the small oil filter in there and replace that, say, every other year ...putting you at what, 6K mile change interval?!! Factory recommends 15K on the large filter, 30K on the small. While I wouldn't go that long, I think you're well within that parameter
FWIW, I put maybe 10K miles/year on my 993. I change oil (Mobil1) every 7-8K along with the main (large) filter, and replace the small filter every other change ...again, that's a 15K interval where the factory recommends 30K so I feel very comfortable that I'm still overmaintaining my baby
.
