Car questions (mostly about oil and filters)

ManBearPig

Diamond Member
Sep 5, 2000
9,173
6
81
1)My car takes 0w-20 and 5w-20. It recommends 5w-20 for winter and 0w-20 for the summer according to the manual, but 0w-20 is like $6+ more expensive. Is it bad if i get 5w-20 all the time? Ive heard its not really a big diff.

2)Are there any brands of oil i should avoid? I get pennzoil i think because its a little cheaper than the other brands.

3)I have a bunch of left over oils of varying weights (0w-20 and 5w-20) that are probably nearing the amount of quarts i need. Can i mix them? Is it bad if theyve been sitting too long?

4)My car takes either 4.5 or 4.6 quarts. Would it be horrible if i just dumped the whole 5 quart container in there?

5)Are all oil filters equal? I just usually get a cheap fram filter from walmart, but there are more expensive frams and other brands as well at other places. Should i NOT be buying a cheap one? We have very easy driving in pretty clean locations (no dust, dirt, etc).

6)For synthetic oil ive heard it has to be changed every 5000 miles. Is this correct? A dude at the store was telling me he changes his every 10-12k miles and his vehicle is at 215K miles or something. He also claims for conventional oil you have to change it every 5-7K miles and that he has 2-3 vehicles with 200K+ miles on them.

7)How often should i change my air filter?

Thanks for the help, more questions will come as i remember them lol.
 

bruceb

Diamond Member
Aug 20, 2004
8,874
111
106
1): 0W20 and 5W20 should be interchangeable in most climates. Some newer motors have very tight tolerances and the 0W20 may be the preferred choice, but 5W20 will work if it is listed in owners man.

2): I use either Pennzoil, Castrol or Mobil 1 ... all full synthetics

3): You can with no issues.

4): Won't make any difference between 4.5 and 4.6 qts. What you should do is fill the Oil Filter up first. That will take about .5qt of oil. Then put the rest and 4 more qts into motor.

4): Oil changes: 5,000 - 7,000 miles is fine for full synthetic, unless you do a lot of stop / go driving. Then I would do it around 4,000 - 5,000 miles.

5): I use Fram myself. AC Delco or car makers brands are fine as are Mobil 1 filters.

6): Oil life monitors are fairly accurate. Change it when it
gets down to about 15% oil life (if your car shows in percentage)

7): Air filter should be checked and replaced every 2 years or about 30,000 miles. More often if you are in a very dusty area.
 
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bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
The answer to #1 depends on the climate where you live. See down here in America's Wang - I can ignore the W part since it never gets cold enough to be an issue. Thus the only part that comes into play is the high temperature viscosity:

http://www.funtrivia.com/askft/Question33842.html

I'm curious why the vehicle recommends the slightly thicker oil for cold weather. I would assume they would want it to be thinner for easier starting. Shrugs.

In any event, the difference is minimal.

2. I use Mobil 1 exclusively. Only 100% synthetic in my cars. I'd considered amsoil but availability is always an issue with that stuff where I live. Avoid store brand or off-brand oil.

3. Yes. Oil doesn't have an expiration date.

4. You should fill your vehicle to the top of the operating range on the dipstick with the vehicle hot and off. Putting a half quart more will cause your motor to burn it off or blow it back into the air filter. Not horrible but its something that you don't need to do, it adds carbon to the motor.

5. Again I stick with Mobil 1 filters on both of my cars. Fram filters have a bad rap but there is nothing inherently wrong with them. Purolator, Wix etc are all fine.

6. You can do extended oil change intervals. The full answer is "When its used up and starts to break down". These days even dino oil is barely starting to be used up and break down at 7k. The 3k OCI is a relic, and synthetics can last forever. 20k with very good synthetics aren't out of the question, but most people shouldn't push it that far. I do 7500 mile OCI with full-synth as above. When I had a POS beater I did 5k OCI with dino and that motor had 240k miles.

7. I don't change mine - its a K&N, but paper filters should be done "when they are dirty" - so like 20k, every couple oil changes.
 

ManBearPig

Diamond Member
Sep 5, 2000
9,173
6
81
I'm curious why the vehicle recommends the slightly thicker oil for cold weather. I would assume they would want it to be thinner for easier starting. Shrugs.

Thanks for the info guys. I was also curious about this, as was my brother in law. Unless im completely retarded and cant read it, it had an arrow pointing left and an arrow pointing right, with corresponding temp ranges getting lower and higher, respectively, and the oil weights i said above them (5w-20 for colder, 0w-20 for hotter).
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
4)My car takes either 4.5 or 4.6 quarts. Would it be horrible if i just dumped the whole 5 quart container in there?

It could be if your crank starts splashing through oil thats in the sump and aerates it, this could lead to an oil-starvation issue and a 'sploded engine in the worst case. Fill it to the top of the dipstick, but no more.
 

thescreensavers

Diamond Member
Aug 3, 2005
9,916
2
81
I would pass on fram filters, you can get a purolator or wix for the same price and are built way better.
 

Meghan54

Lifer
Oct 18, 2009
11,684
5,228
136
I would pass on fram filters, you can get a purolator or wix for the same price and are built way better.



Amen to that. Just bought a riding mower, used, over the weekend. Had a Fram oil filter on it. Guess for a lawnmower engine it's not too bad, but it got taken off yesterday and replaced with a Purolator filter.....and the Fram was brand new.

Today's Fram is nothing like the Fram of decades past. Used to be Fram was THE filter....now it's just a cheaply built can for the WalMart crowd to buy.
 

kaerflog

Golden Member
Jul 23, 2010
1,899
4
76
I think it helps to know what car you have.
If its a new $30K car, then yeah, use the best for it.
Now if its a $4K beater......
 

Kaervak

Diamond Member
Jul 18, 2001
8,460
2
81
I would pass on fram filters, you can get a purolator or wix for the same price and are built way better.

If you time your purchases right, you can get PureOne's for $1.00 a piece. Advance Auto coupons and Purolator MIRs for the win. :D
 
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bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
And another sucker was born.............

Yup, I've heard allllll the bad press and the good press. To me: $40 one time purchase > $5 purchases multiple times. I don't buy the greater airflow claims and I keep mine clean and oiled. I have a small turbo on one of my PT's and it certainly sounds "different" than a paper filter. No measurable gains though. It's the convenience more than anything else. (both of them are the drop-ins).
 

Vette73

Lifer
Jul 5, 2000
21,503
9
0
What is your car? The 0w20 "should" be a better winter oil than the 5w20.

But you could even run 5w30 if you wanted and still be fine. The Xw20 is for CAFE standards not engine protection. So Xw20 or 5w30 is fine.


Try to do 4.5 and then top off. 5qts may not be a problem but in some cars it could.

DON'T use fram. They are junk and cost to much. Use Motorcraft, Wix, Purloator, Bosch, etc...

Air filter depends on the size of the filter and where you live. My old Corvette had a large filter and did not get very dirty. My old CTS though had a smaller filter and I changed that at 25k.
 

the DRIZZLE

Platinum Member
Sep 6, 2007
2,956
1
81
Yup, I've heard allllll the bad press and the good press. To me: $40 one time purchase > $5 purchases multiple times. I don't buy the greater airflow claims and I keep mine clean and oiled. I have a small turbo on one of my PT's and it certainly sounds "different" than a paper filter. No measurable gains though. It's the convenience more than anything else. (both of them are the drop-ins).

I'd run no filter before I'd use a K&N.
 

Meghan54

Lifer
Oct 18, 2009
11,684
5,228
136
Yup, I've heard allllll the bad press and the good press. To me: $40 one time purchase > $5 purchases multiple times. I don't buy the greater airflow claims and I keep mine clean and oiled. I have a small turbo on one of my PT's and it certainly sounds "different" than a paper filter. No measurable gains though. It's the convenience more than anything else. (both of them are the drop-ins).


Even though it's a one time purchase and you keep it cleaned and oiled, you still didn't address the massively increased amount of dirt your engine is ingesting via the air intake. Guess longevity of your motor isn't much of a concern.
 

bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
Massively is not the operative word here. Tests show perhaps a 1% filtration difference betwixt a paper filter and the K&N. My wife obtained her PT at 37,000miles, and it now has 128,000. I immediately installed the air filter. At 118,000 miles we did the timing belt, and since I pulled the motor out to make things easier I pulled the heads and the pan off and checked EVERYTHING out. There was no evidence of gunk, buildup, extra carbon, scoring of valves, buildup of dirt in the pan, on any part of the inside of the bottom end, top end, air path, fuel path, etc. There was a fuel injector with a little less than normal flow (on my ghetto field test, the spray pattern wasn't perfect, but thats to be expected, I sent them out to be cleaned and they came back perfect) There was only the typical exhaust path wear, and not too much of that. The valves were worn gently as expected and I didn't need to replace any of them. The plenum and intake manifold were almost completely clean. The cylinder walls were perfectly smooth and while I didn't pull the pistons out and do a ring job, since all 4 cylinders were almost factory smooth I didn't see a need to go that far. I attribute the serious lack of wear on this motor due to my prodigious use of full synthetic oil and quality filters (only mobil 1 10w30 and filters have ever gone into either of these cars)

On my PT I obtained it at 42,000 miles and also immediately put on a K&N filter. At 98,000 miles I did my own timing belt, and also pulled my heads. I left the bottom end intact based on how little wear existed on my wifes bottom (lol). I found more valve wear than I saw on my wifes. But I drive mine a lot more. It was nothing to be attributed to using a non-replaceable filter.

I did a lot of that above specifically because I've read both good and bad things about permanent air filters. I wanted to see the evidence for myself. In 2 personal cases I can attest that a permanent air filter (the K&N drop-in) does NOT let in "Massive amounts" or any more than ordinary amounts of particulates, carbon, dirt, gunk, whatever. The inside of both of my motors are very very clean after years and years of use and many many miles over varied terrain including; Mountains of Appalachia, Farms of the Midwest, smokies, TN, VA, NY, but mostly sunny South Florida.

The longevity of my motor is a serious concern, and as stated above, and proven to myself with my own eyes and 25 years of mechanical experience, the use of that filter does not compromise anything.

The two folks that have commented may have different opinions than my own. I don't work for, nor do I benefit from K&N in any way. I also know that this is the sort of stuff that starts flamewars. Using or not using a permanent filter is a religious decision for a lot of people. However blanket statements such as "this filter lets in massive amounts of dirt" are patently false, my own experience contradicts that, along with tests from people like Bob the Oil guy. (His tests agreed that while the K&N flows 1% better or so, it also let about 1% more particulate matter through).

Thats on the top end too, so over the course of 5 years I would estimate something along the order of a half a cup worth of dirt might be filtered by a typical paper filter (If you measure that by what I find in my air intake box, + what I'm used to finding on paper filters. 1% of 4 oz is barely measurable. And its only the really fine stuff that gets through, which usually burns up in the motor anyway.
 

CraigRT

Lifer
Jun 16, 2000
31,440
5
0
I use Wix air and oil filters and whichever name brand oil is on sale.
It's working well for me.
 

WhoBeDaPlaya

Diamond Member
Sep 15, 2000
7,415
404
126
What is your car? The 0w20 "should" be a better winter oil than the 5w20.
But you could even run 5w30 if you wanted and still be fine. The Xw20 is for CAFE standards not engine protection. So Xw20 or 5w30 is fine.
^ This. My car lists 5W-20 as the official oil, even though earlier models (with the same engine) list 5W-30.
UOAs performed with Pennzoil Ultra 5W-20 and 5W-30 confirmed that using 5W-30 is fine (06 Lincoln LS) and the wear levels were better with the 5W-30. I also liked the sound better with 5W-30.


OP : I'd only recommend mixing the various oils if they're of the same brand, due to differing additives between brands. If the oil containers have not been opened, then they're fine. I usually stock up when there's a sale going on (eg. 2x 5q jugs of Mobil 1 5W-20 for $20) and use it anywhere from 1/2 to 1 year later.
 
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Throckmorton

Lifer
Aug 23, 2007
16,829
3
0
Massively is not the operative word here. Tests show perhaps a 1% filtration difference betwixt a paper filter and the K&N. My wife obtained her PT at 37,000miles, and it now has 128,000. I immediately installed the air filter. At 118,000 miles we did the timing belt, and since I pulled the motor out to make things easier I pulled the heads and the pan off and checked EVERYTHING out. There was no evidence of gunk, buildup, extra carbon, scoring of valves, buildup of dirt in the pan, on any part of the inside of the bottom end, top end, air path, fuel path, etc. There was a fuel injector with a little less than normal flow (on my ghetto field test, the spray pattern wasn't perfect, but thats to be expected, I sent them out to be cleaned and they came back perfect) There was only the typical exhaust path wear, and not too much of that. The valves were worn gently as expected and I didn't need to replace any of them. The plenum and intake manifold were almost completely clean. The cylinder walls were perfectly smooth and while I didn't pull the pistons out and do a ring job, since all 4 cylinders were almost factory smooth I didn't see a need to go that far. I attribute the serious lack of wear on this motor due to my prodigious use of full synthetic oil and quality filters (only mobil 1 10w30 and filters have ever gone into either of these cars)

On my PT I obtained it at 42,000 miles and also immediately put on a K&N filter. At 98,000 miles I did my own timing belt, and also pulled my heads. I left the bottom end intact based on how little wear existed on my wifes bottom (lol). I found more valve wear than I saw on my wifes. But I drive mine a lot more. It was nothing to be attributed to using a non-replaceable filter.

I did a lot of that above specifically because I've read both good and bad things about permanent air filters. I wanted to see the evidence for myself. In 2 personal cases I can attest that a permanent air filter (the K&N drop-in) does NOT let in "Massive amounts" or any more than ordinary amounts of particulates, carbon, dirt, gunk, whatever. The inside of both of my motors are very very clean after years and years of use and many many miles over varied terrain including; Mountains of Appalachia, Farms of the Midwest, smokies, TN, VA, NY, but mostly sunny South Florida.

The longevity of my motor is a serious concern, and as stated above, and proven to myself with my own eyes and 25 years of mechanical experience, the use of that filter does not compromise anything.

The two folks that have commented may have different opinions than my own. I don't work for, nor do I benefit from K&N in any way. I also know that this is the sort of stuff that starts flamewars. Using or not using a permanent filter is a religious decision for a lot of people. However blanket statements such as "this filter lets in massive amounts of dirt" are patently false, my own experience contradicts that, along with tests from people like Bob the Oil guy. (His tests agreed that while the K&N flows 1% better or so, it also let about 1% more particulate matter through).

Thats on the top end too, so over the course of 5 years I would estimate something along the order of a half a cup worth of dirt might be filtered by a typical paper filter (If you measure that by what I find in my air intake box, + what I'm used to finding on paper filters. 1% of 4 oz is barely measurable. And its only the really fine stuff that gets through, which usually burns up in the motor anyway.

Look at the link in my sig. K&N lets in 45x as much dirt.

You know how they say they filter 99.2%? Well that 0.8% is 45x what other filters let through to your engine. That is a huge difference. It's not a 1% difference.
 

bobdole369

Diamond Member
Dec 15, 2004
4,504
2
0
Look at the link in my sig. K&N lets in 45x as much dirt.

You know how they say they filter 99.2%? Well that 0.8% is 45x what other filters let through to your engine. That is a huge difference. It's not a 1% difference.

Meh, thats some funny math, sounds more like advertising math to me. It's not a huge difference, it's "1%" (or whatever it was exactly, paper filters don't achieve 100% either) and I've seen numbers pretty much all over the board with "scientific tests". My own eyes show that no problem exists. 1% out of 100% compared to 0.2% out of 100% might be "50 times more" but it would be 200 grains of dust fiber - compared to 2 grains of dust fiber, when 20000 grains are filtered.

If you'd rather change your paper filter so often or use some other media - by all means.
 

ShawnD1

Lifer
May 24, 2003
15,987
2
81
Meh, thats some funny math, sounds more like advertising math to me.

That's how statistics are reported. If 1 in 1000 people die from lung cancer and 20 in 1000 smokers die from lung cancer, you would say smokers are 20x higher risk of getting cancer. The way you're expecting to report it would basically be a wash, 0.1% vs 2%, smokers are 1.9% higher chance of getting cancer?