5W-30 vs. 10W-30

I own a 1998 Honda Civic EX Sedan. It has 160,000 miles on it. I recent
got an oil change on it.

During the life of the car, I have used 5W-30 motor oil. However, some of
the mechanics at my oil change place have said that I should switch to
10W-30, due to the mileage on my car, and because 10W-30 is thicker.

Should I take heed to this advice?

 

No.

I tried that a while back and 10W-30 made absolutely NO difference in my
oil consumption. My car's been fed 5W-30 since day one. It now has 260,000
miles on it and gets over 2,000 miles per US quart.

How's your oil consumption?

 

Unfortunately, I did not monitor my oil consumption.

As of this message, I will begin doing so.

I simply get my oil changes around every 4,000 miles or so. If I was able
to get 2,000 miles per US quart, and 3.8 quarts of new oil are installed
per go around, could I, in theory, reach 7,500 miles between oil changes?

 

Not to dispute Tegger's claim, but just to offer evidence that your
mechanics are not totally whack-o: I have seen internet sites that suggest
switching to a higher viscosity oil for older cars. It's worth googling.

 

Oil is not consumed as fuel is. If it was, they wouldn't have to drain it.

How dirty is your oil at 4000 miles is the question? At 148,000, my '01
Accord doing 7K oil changes (I have a long highway commute) the oil is
dirty, but not black.

If you are consuming oil, that means you are burning oil. Others can give a
better description of the mechanics behind how oil gets into the fuel being
burned, but in essence, in those cases a thicker oil might not sneak by the
way thinner oil does. If you're not burning any oil (as in 3.8 quarts are
coming out at each change) then there is no need for thicker oil as you do
not have a problem with the thin stuff.

 

I've seen that also, but usually in reference to burning oil and how to stop
said oil from making it into the combustion chamber. If the thin stuff
isn't sneaking by the rings, then switching to thicker stuff won't have any
benefits.

 

:

I think the general idea in this is that the thinner oil will seap
thru seals and gaskets that are aging. It's the same principle of
why you don't use synthetic oil on old cars. It's so slick that it
will leak in almost every seal. Another thing is the piston rings
that might not scrape the oil from the cylinder walls.

 

Our local Honda dealer only offers 5-20 for all Hondas new and old with the
claim that Honda has authorized this. My Prelude calls for 5-30 or possibly
10-30 in hot weather which we have in abundance here in mid GA in Summer.
Am I right to be uneasy about using 5-20.

 

Begin using 10W-30, you mean? Not really a great idea.

10W will flow less readily than 5W when cold, while the 30 side of it will
get consumed by the engine identically when hot.

Mathematically you could, but this too is not a good idea. How many months
does it take you to reach 7,500 miles? How long do you intend on keeping
the car?

 

The difference between 5W-30 and 10W 30 is its behavior when cold. Once
it's warmed up, there is no difference between the two.



It's the same principle of

Utter nonsense.

 

I'm not seeing your posts, for some reason, just other peoples' replies to
them.

If an engine is consuming oil, it means the oil control rings are worn out.
If you were using 5W-30 and were experiencing excessive oil consumption,
you'd have to move up to something like a 20W-50 before it made any
meaningful difference. Simply going up from 5W to 10W will do absolutely
nothing, especially when the hot end of it is still the same (30).

My oil consumption used to be roughly 8K/qt when the car had 100K miles.
Now I'm down to just over 2K miles. That's with 5W-30 and 260K on the
clock.

My oil check procedure is this:
1) Change oil
2) With engine COLD and having sat overnight, check oil and note dipstick
reading
3) Drive car 1,000 miles
Repeat from #2.

The car is ALWAYS checked with it parked in the identical same spot, at the
same slope.

When I temporarily switched from 5W-30 to 10W-30, there was zero difference
in oil consumption. I moved back to 5W-30 to take advantage of 5W-30's
slightly better cold flow characteristics.

 

Okay then fill your car with synthetic and see what happens.

 

What year is your Prelude? How many miles?

Try it for one go-around and see what happens. I'll bet you won't notice
any difference of any kind. The 5W-20 is part synthetic, so it has slightly
better film strength. Film strength is probably comparable to that of 5W-
30.

 

I agree. Jumping the gun on switching to a higher visc. oil may reduce
engine efficiency, as well.

 

01 62k miles. I have been running 5-30 Mobil 1 for the past 30k miles,
rather than risk the Honda 5-20. Maybe overkill though since I change oil
every 3700 miles anyway.

 

What's the "risk" with the factory recommended 5w-20? My '01 Accord EX-v6
with 148,000 miles and 7k between changes is still running strong, running
smooth and starting up on the first try.

I bought a Honda for durability and economics. You seem to be wasting a bit
of the economical advantage of a Honda.

 

You didn't say that. I assumed you were using mineral oils. Mobil 1 is a
pure synthetic. Honda's 5W-20 is part synthetic, part mineral. Mobil 1 is
the better oil of the two.

You are performing excellent auto maintenance! You can look forward to long
life from your engine.

 

I like the Prelude and want to keep it for a long time. Thanks for the
input.

 

I did google and ran into the AMSOIL oil, amsoil.com.
And I had read all the information on this web site, how accurate of the
information?
TA

 

Functionally, AMSoil and Mobil 1 may be taken as equivalents.