Rev. Tom Wenndt wrote:
> Is the '07 Elantra the first year of the re-design, or the last year of the
> old one? And, in any case, did the engine change one bit during the
> re-design (I get the impression the answer is 'no').
>
> The Kia Spectra uses basically the exact same 2.0L engine. Mine specifies
> 5W20/30. That is a strange designation, but I have a hunch it means that
> either 5/20 or 5/30 is acceptable. I use the 5/20 in Winter and 5/30 in
> Summer, always using synthetic oil. I doubt I will have trouble, and also
> doubt I will fiddle with a 0W weight, even in synthetic.

I don't blame you for not experimenting. I would try a 0 weight oil if
it wasn't for the fact that all I can find around here is Mobil one in
quarts, which costs double what I pay for the synthetic oil I've been
buying in 5 quart jugs.

> One more question about the 0W oils. Would that not cause a lot of problems
> for things like valve cover gaskets? Through the years, I have already had
> enough trouble, and enough cars that had oil seep through them at some
> point, and that, of course, was heavier 5W oil.

Why would it make any difference? Once the oil is hot, the base weight
of the oil makes little or no difference. All xW-20 (or xW-30) oils are
going to be similar in viscosity when hot. In my experience, if a valve
cover gasket is installed onto a clean head and valve cover and the
bolts are properly tightened, it won't leak. If a leak does develop
(usually due either to the bolts loosening or being overtightened and
splitting the gasket) the only way to get rid of it reliably is to clean
the surfaces completely and replace the gasket.

 

Brian Nystrom wrote:
> Rev. Tom Wenndt wrote:
>> Is the '07 Elantra the first year of the re-design, or the last year
>> of the old one? And, in any case, did the engine change one bit
>> during the re-design (I get the impression the answer is 'no').
>>
>> The Kia Spectra uses basically the exact same 2.0L engine. Mine
>> specifies 5W20/30. That is a strange designation, but I have a hunch
>> it means that either 5/20 or 5/30 is acceptable. I use the 5/20 in
>> Winter and 5/30 in Summer, always using synthetic oil. I doubt I will
>> have trouble, and also doubt I will fiddle with a 0W weight, even in
>> synthetic.
>
> I don't blame you for not experimenting. I would try a 0 weight oil if
> it wasn't for the fact that all I can find around here is Mobil one in
> quarts, which costs double what I pay for the synthetic oil I've been
> buying in 5 quart jugs.
>
>> One more question about the 0W oils. Would that not cause a lot of
>> problems for things like valve cover gaskets? Through the years, I
>> have already had enough trouble, and enough cars that had oil seep
>> through them at some point, and that, of course, was heavier 5W oil.
>
> Why would it make any difference? Once the oil is hot, the base weight
> of the oil makes little or no difference. All xW-20 (or xW-30) oils are
> going to be similar in viscosity when hot. In my experience, if a valve
> cover gasket is installed onto a clean head and valve cover and the
> bolts are properly tightened, it won't leak. If a leak does develop
> (usually due either to the bolts loosening or being overtightened and
> splitting the gasket) the only way to get rid of it reliably is to clean
> the surfaces completely and replace the gasket.

I wish I knew if that were the case. I believe that oils are tested
only at two temperatures, and I believe (this is from memory so don't
take it to the bank) these are 0 and 100 degrees C. I'd like to see a
full viscosity vs. temperature as I'd be really surprised if the 0W20
oils were completely equivalent to 5W-20 at the hot end. There is no
free lunch and I'll bet you lose something at the top to gain at the
bottom temp range.

I don't own a car that allows both 0W20 and 5W20, but I have a 2003
Chrysler minivan that allows both 5W30 and 10W30. Since both are 30 at
the hot end, your argument above says that they are equivalent when hot,
right? However, the chart in my Chrysler owner's manual suggests
otherwise. The temperature range for the 5W30 runs from 100F downward
with an arrow that doesn't end. The range for 10W30 starts at 0F and
runs upward with no end. It runs past 100F whereas the 5W30 line ends
exactly at 100F. So, for temps above 100F, ONLY 10W30 is allowed.

I can't say that the same holds true for the 20 weight oils, but I have
a strong suspicion that it does.

So, yes, anyone can experiment if they want and use 0W20 in a car for
which only 5W20 is specified, but I wouldn't do that with my car, at
last not during the warranty period.

Matt

 

"Matt Whiting" <whiting@epix.net> wrote in message
>
> I wish I knew if that were the case. I believe that oils are tested only
> at two temperatures, and I believe (this is from memory so don't take it
> to the bank) these are 0 and 100 degrees C. I'd like to see a full
> viscosity vs. temperature as I'd be really surprised if the 0W20 oils were
> completely equivalent to 5W-20 at the hot end. There is no free lunch and
> I'll bet you lose something at the top to gain at the bottom temp range.

Perhaps the certifications are done at two temperatures, but I'd have to
think that major oil companies that spen millions of $$$ on research have
tried the oils at other temperatures and plotted curves. Any worthwile
engineer would have done that just out of curiosity.

From http://en.wikipedia.org/wiki/Motor_oil
The governing SAE standard is called SAE J300. This "classic" method of
defining the "W" rating has since been replaced with a more technical test
where a "cold crank simulator" is used at increasingly lowered temps. A 0W
oil is tested at -35°C, a 5W at -30°C and a 10W is tested at -25°C. The
real-world ability of an oil to crank in the cold is diminished soon after
put into service. The motor oil grade and viscosity to be used in a given
vehicle is specified by the manufacturer of the vehicle (although some
modern European cars now make no viscosity requirement), but can vary from
country to country when climatic or mpg constraints come into play. Oil
circulates through the piston oil rings to cool and lubricate the
compression rings. Inside gasoline engines, the top compression ring is
exposed to temperatures as high as 500°F.





but I have a 2003
> Chrysler minivan that allows both 5W30 and 10W30. Since both are 30 at
> the hot end, your argument above says that they are equivalent when hot,
> right? However, the chart in my Chrysler owner's manual suggests
> otherwise. The temperature range for the 5W30 runs from 100F downward
> with an arrow that doesn't end. The range for 10W30 starts at 0F and runs
> upward with no end. It runs past 100F whereas the 5W30 line ends exactly
> at 100F. So, for temps above 100F, ONLY 10W30 is allowed.
>

Sure, the typical owner's manual has a perfect engineering data and gives
exact specifications on such things. Matt, you know better. It is stated
that way to make it easy for consumers to decide what oil to buy. If you
happened to have 5W in the crankcase from your last change and suddenly
found yourself down south at 101 degrees, should you immediately shut down
the engine and have the car towed to an oil change shop?

 

Edwin Pawlowski wrote:
> "Matt Whiting" <whiting@epix.net> wrote in message
>> I wish I knew if that were the case. I believe that oils are tested only
>> at two temperatures, and I believe (this is from memory so don't take it
>> to the bank) these are 0 and 100 degrees C. I'd like to see a full
>> viscosity vs. temperature as I'd be really surprised if the 0W20 oils were
>> completely equivalent to 5W-20 at the hot end. There is no free lunch and
>> I'll bet you lose something at the top to gain at the bottom temp range.
>
> Perhaps the certifications are done at two temperatures, but I'd have to
> think that major oil companies that spen millions of $$$ on research have
> tried the oils at other temperatures and plotted curves. Any worthwile
> engineer would have done that just out of curiosity.
>
> From http://en.wikipedia.org/wiki/Motor_oil
> The governing SAE standard is called SAE J300. This "classic" method of
> defining the "W" rating has since been replaced with a more technical test
> where a "cold crank simulator" is used at increasingly lowered temps. A 0W
> oil is tested at -35°C, a 5W at -30°C and a 10W is tested at -25°C. The
> real-world ability of an oil to crank in the cold is diminished soon after
> put into service. The motor oil grade and viscosity to be used in a given
> vehicle is specified by the manufacturer of the vehicle (although some
> modern European cars now make no viscosity requirement), but can vary from
> country to country when climatic or mpg constraints come into play. Oil
> circulates through the piston oil rings to cool and lubricate the
> compression rings. Inside gasoline engines, the top compression ring is
> exposed to temperatures as high as 500°F.

You don't trust your owner's manual, but you trust Wiki? That is really
funny! I haven't laughed this hard in a week!!


> but I have a 2003
>> Chrysler minivan that allows both 5W30 and 10W30. Since both are 30 at
>> the hot end, your argument above says that they are equivalent when hot,
>> right? However, the chart in my Chrysler owner's manual suggests
>> otherwise. The temperature range for the 5W30 runs from 100F downward
>> with an arrow that doesn't end. The range for 10W30 starts at 0F and runs
>> upward with no end. It runs past 100F whereas the 5W30 line ends exactly
>> at 100F. So, for temps above 100F, ONLY 10W30 is allowed.
>>
>
> Sure, the typical owner's manual has a perfect engineering data and gives
> exact specifications on such things. Matt, you know better. It is stated
> that way to make it easy for consumers to decide what oil to buy. If you
> happened to have 5W in the crankcase from your last change and suddenly
> found yourself down south at 101 degrees, should you immediately shut down
> the engine and have the car towed to an oil change shop?

I never said it was "perfect engineering" data, whatever that is. I've
been an engineering for 25 years and I've never heard of such an animal.
However, the fact remains that the top end of the chart is different
and I suspect it is different for a reason. It would be easier for
Chrysler to just recommend 5W30 for ALL conditions and make it real easy
for the consumer to decide. The fact that they specify a different oil
for operation above 100F says to me that they feel 10W30 provides better
high temp protection than 5W30. I've seen no engineering data, perfect
or otherwise, that tells me how either oil performs across the full
temperature spectrum. I'd love to see it though, but in the meantime
I'm going to use the oil as specified in my owner's manual as that is
the best information I have ... almost certainly better than Wiki!!

Matt

 

"Matt Whiting" <whiting@epix.net> wrote in message
> You don't trust your owner's manual, but you trust Wiki? That is really
> funny! I haven't laughed this hard in a week!!

Apples and oranges. The owners manual was in regard to two choices. Wiki
was in regard to testing methods that show more than two temperatures. They
do get some things right or at least close enough.


>
> The fact that they specify a different oil for operation above 100F says
> to me that they feel 10W30 provides better high temp protection than 5W30.
> I've seen no engineering data, perfect or otherwise, that tells me how
> either oil performs across the full temperature spectrum. I'd love to see
> it though, but in the meantime I'm going to use the oil as specified in my
> owner's manual as that is the best information I have ... almost certainly
> better than Wiki!!

You may be right, but the 100 degree cutoff as specified in the manual is
not accurate either. I'm confident that there is plenty of overlap near the
specified 100 degree mark. 5W will not suddenly fail at 101 degrees.

 

Edwin Pawlowski wrote:
> "Matt Whiting" <whiting@epix.net> wrote in message
>> You don't trust your owner's manual, but you trust Wiki? That is really
>> funny! I haven't laughed this hard in a week!!
>
> Apples and oranges. The owners manual was in regard to two choices. Wiki
> was in regard to testing methods that show more than two temperatures. They
> do get some things right or at least close enough.
>
>
>> The fact that they specify a different oil for operation above 100F says
>> to me that they feel 10W30 provides better high temp protection than 5W30.
>> I've seen no engineering data, perfect or otherwise, that tells me how
>> either oil performs across the full temperature spectrum. I'd love to see
>> it though, but in the meantime I'm going to use the oil as specified in my
>> owner's manual as that is the best information I have ... almost certainly
>> better than Wiki!!
>
> You may be right, but the 100 degree cutoff as specified in the manual is
> not accurate either. I'm confident that there is plenty of overlap near the
> specified 100 degree mark. 5W will not suddenly fail at 101 degrees.

Yes, I agree 100% that 100 F isn't a "fall off the cliff" number. That
wasn't my point. The point is that the 10W30 shows a higher temperature
suitability than does 5W30 even though the "hot" viscosity number is the
same for both oils.

I was getting my BMW motorcycle reading for riding and decided to check
the owner's manual for it and found the exact same thing. It shows two
multigrade oils with the same upper end viscosity number, but different
"winter" numbers and the oil with the lower "winter" number is also
limited on the high temperature end whereas the other oil isn't. I
think these were heavier grades with a 40 or 50 weight upper end, but
the chart was exactly analogous to the Chrysler chart. So, I personally
do not think one can say that just because the upper viscosity numbers
for two different range multigrade oils are the same, that they have the
same performance in hot conditions.

Matt