Smoother with 5w30 Oil

gcretro · Post by **gcretro** » Mon Nov 12, 2012 8:58 pm

04 Neon SE

Last time i used 10w30 mobile high mileage oil in summer, while this time switched back to 5w30 Valvoline max life.

I noticed the motor being more quieter now & smoother. Never again 10w.

gtownv6 · Post by **gtownv6** » Mon Nov 12, 2012 9:13 pm

I thought they called for 5w-30 from the factory anyway, why weren't you running the correct oil in the first place?

Post by **occasional demons** » Mon Nov 12, 2012 10:06 pm

A lot of "high mileage" oils are 10wxx. But if you look around, you can find them in 5wxx.

Using a heavier weight in a high mileage engine really makes no sense. The more viscosity, the more it will cling to the cylinder walls. The tired oil control rings then let more oil into the combustion chamber. Thus you consume more oil.

A lighter viscosity pumps faster, takes less parasitic drag, and can actually give you better oil pressure, to a point. If the bearings have .010" of clearance, naturally it wouldn't.

But I have used Mobil1 0w30 in my XJ, and it actually gained about 5 psi cold idle.

gtownv6 · Post by **gtownv6** » Mon Nov 12, 2012 10:36 pm

I could only see heavier weight oil being beneficial if you have too much clearance on the crank journals and have excessive internal oil leakage. But at that point the engine is toast no matter what you do to it

gcretro · Post by **gcretro** » Mon Nov 12, 2012 10:40 pm

gtownv6 wrote:I thought they called for 5w-30 from the factory anyway, why weren't you running the correct oil in the first place?

Oh well my mechanic said 10w is better in summer so he put that. I changed it now after 3.5K

Post by **occasional demons** » Tue Nov 13, 2012 12:04 am

Your mechanic is too old school.

I bet the oil temps when warmed up, aren't all that different between summer and winter. While ambient temps do have some impact, the thermostat is still the major factor in engine temps. My temps are about the same year round.

And to the fact that at operating temp, the first number means nothing. They both are at 30 when hot. So ask him how a heavier cold viscosity is helping the engine.

It takes longer to pump, meaning it takes longer to get pressure to the bearings.

DetergentCandy · Post by **DetergentCandy** » Tue Nov 13, 2012 12:04 am

I'm pretty sure the manual specifies 5w30 or 10w30 depending on the temperature you're driving in.

For me, since Phoenix summers don't drop below 90 degrees at night and stay above 105 during the day, 10w30 is a good choice.

gcretro · Post by **gcretro** » Tue Nov 13, 2012 10:19 am

that's right. manual (which I found I still had

) does say 5w or 10w.

But I am sticking to 5w,30 Valvoline maxlife definitely smoother.

Post by **racer12306** » Thu Nov 15, 2012 8:51 am

Oil Edumacation:

5w30 vs 10w30 really only makes a difference on start up. Both weights flow similar once they reach temperature. There are even some 10w30 oils that are actually thinner at temperature than 5w30 oils (per the cSt on the data sheet).

The biggest difference is 10w30 is a more "natural" viscosity spread. 5w30 requires Viscosity Index Improvers (VII) to maintain the spread, but it doesn't require a lot (like a 5w40 does).

In normal climates, it doesn't matter between 5w30 and 10w30 in your Neon. Realistically, you have to get pretty cold before you have to use a 5w30 over a 10w30. The reason for hotter climates liking 10w30 over 5w30 is because of the lower amount of VIIs. This allows the oil to handle the heat a little better.