So has ANYONE officially changed from 0W-20 to 5W30 in summer type weather and done an oil analysis? I also expect the MPG to go down, does anyone have experience with that as well? Sorry again I just never saw an oil analysis done.

Im at 165.6k miles on a 12 XKR.

Loth

 

I look forward to seeing .your comparative analysis ;-)

 

La réponse se trouve ici :
Bonne vidéo
!

 

YouTube search query: 0w 20 VS 5w 30

 

I see that 0W40 is an option in lower threads.

 

I'm probably going to run 0W40 next oil change. 0W to help get pressure to tensioners faster, and 40 because I want something that is going to be shear stable at high temps. Penrite 10 Tenths 0w 40 is easy for me to get and is blended with PAO/Esters so good for hard driving (of which I do a lot).

 

The disadvantage is that the wider the range (i.e. the lesser the change in viscosity), the sooner that the oil shears out of spec. As always with such things, there is always a compromise.

Richard

 

I didn't know that, so thank you for the info. I'd suppose this would be a bad thing for a daily driver driven hard - I'd be lucky to see even 3000km between oil changes.

 

You have analysed the issue perfectly. If you do use a wider spec oil, you should then change the oil more frequently and, as you say, the harder you work the engine, the shorter those intervals should be.
The only way to really pin the figures down would be to have the oil tested as mentioned by the OP and you then have something concrete to work with but I would think that halving the recommended oil change interval for the wide spec oil would probably be wise.

Richard

 

I went to 5w30 Valvoline Restore when I bought the car, because why not? I like the idea of an oil analysis, but what if there's high copper or moly or johnson-rod debris or whatever? Then what? Scrap the car? I get the science and preventive thoughts, but unlike a colonoscopy, I'm not sure I want to know.

 

in my mind, if you see that the rod bearings are on their way out, it’s a lot easier (and cheaper) to prepare to replace em rather than your crank/oil filter system later.

 

One question I never see discussed in these threads is how the variable valve timing system, with its very small oil passages, will respond to oil of higher viscosity.

I would welcome input from any of our experts.

Cheers,

Don

 

I was thinking that would be a larger issue if using a higher cold weight IE a 10w or 15w. I know the passages are tiny in the VVTI system so a slower oil when starting up could cause sluggishness.

 

It's worth remembering that when the engine is cold the oil is a many orders of magnitude thicker than it is when the engine is hot. Because the cold oil is thick and is gradually thinning as it warms up, the engine has to be designed so as to be able to circulate the cold oil through all the galleries, bearings etc otherwise initial wear would be so high that the engine would soon fail. Once the oil starts to heat up and become thinner, then circulation becomes more effective.

Of course, there is no way around the fact that engine wear is higher during the warm-up period, even with a 0W oil, which is why you should not stress or rev an engine until it is up to temperature.

Richard