Changing oil using synth blend, 5w-30 or 10w-30??

[redcalimp5]

I'll be doing my first oil change since I've recently bought my 2003 P5 this weekend. The previous owner I bought it from used regular 5w-30 oil, but I would like to only put synthetic blend oil for every change from now on.

Does it really matter whether I decide to put 5w-30 or 10w-30 synth blend in? Also, I was thinking about using a high performance oil filter when I change to out to synth blend, but will it make a difference at all in the car's performance? I don't want to spend extra on an oil filter if it's just going to be a waste of $$$.

I live in So Cal, where the coldest it gets is maybe 35, the warmest 100 in the summer. I only use my car for daily driving and casual weekend driving, too.

Any thoughts or recommendations?

 

[fonzinator]

Since you live in a warm climate, 10w-30 is perfect for you year round. If you have a cold winter (like me in Minnesota), you would switch to the higher viscoscity 5w-30 during the winter and run lower viscoscity 10w-30 during the spring/summer/fall.

I doubt an oil filter can make a noticeable difference in your car's performance (for non-racing applications). Your main concern is the filter's ability to remove particulates from the oil. Both Mobil 1 and Purolator's PureOne are regarded as great filters that trap a high percentage of particulates. You can get a Mobil1 EP filter for $10 at Autozone.

 

[16902]

I would just stick to 10w-30. It has a higher temperature range but doesn't work as well at a colder point (pretty cold). The 5W-30 oil is better during cold winters. You will really be fine with either right now but def use 10w-30 in summer.

Edit: Oh, also a lot of people prefer just the OEM filters from Mazda.

 

[Reitrof]

5w 30. Most engine wear occurs at startup. Engine was designed for 5w30. I use it year round, synthetic. 130k and no issues.

 

[pass the peas]

second the recommendation for oem mazda filter

 

[Hughes412]

I use 5w30. If you don't know and no one has said it. The reason the oil is 5w30 is with the new engines it's vital that the oil gets to the head as fast as possible. The oil thickness starts out at 5 weight until it warms up then turns to 30. With the 5w it gets there faster then if it were 10w. As for filters I use frame tough guard. They have the bypass valve so that the oil pressure doesn't blead down inbetween starts. This will help keep you from getting that dry knock after you get a few thousand miles on it.

 

[Hughes412]

5w 30. Most engine wear occurs at startup. Engine was designed for 5w30. I use it year round, synthetic. 130k and no issues.

Very smart guy!

 

[Sveivo]

Since you live in a warm climate, 10w-30 is perfect for you year round. If you have a cold winter (like me in Minnesota), you would switch to the higher viscoscity 5w-30 during the winter and run lower viscoscity 10w-30 during the spring/summer/fall.

I doubt an oil filter can make a noticeable difference in your car's performance (for non-racing applications). Your main concern is the filter's ability to remove particulates from the oil. Both Mobil 1 and Purolator's PureOne are regarded as great filters that trap a high percentage of particulates. You can get a Mobil1 EP filter for $10 at Autozone.

I think most will agree that 10W-30 is higher viscosity. No?

5w 30. Most engine wear occurs at startup. Engine was designed for 5w30. I use it year round, synthetic. 130k and no issues.

Designed? Where do you get this information? The manual says that 10W-30 is just as good as 5W-30 for a wide temp range.

 

[Hughes412]

I think most will agree that 10W-30 is higher viscosity. No?

Yes 10w is thicker then 5w.
[quoute] Viscosity
The material property that measures a fluid's resistance to flowing. For example, water flows from a tilted jar more quickly and easily than honey does. Honey is more viscous than water, so although gravity creates nearly the same stresses in honey and water, the more viscous fluid flows more slowly.[/quote]

Designed? Where do you get this information? The manual says that 10W-30 is just as good as 5W-30 for a wide temp range.

mine says 5w30 also.

 

[Sveivo]

mine says 5w30 also.

That's weird. They must have updated the manula for 2003. But the engine is the same.

I can post a pic of my manual some time.

 

[clicknext]

My '02 manual says that 10w30 is good only down to just under 0 degrees celcius I believe, while 5w30 is good for significantly lower and the high end does not suffer much. So it would seem that 5w30 is better overall for the car, since you will never even get close to its specified optimum operating limits.

 

[Kansei]

My '02 manual says that 10w30 is good only down to just under 0 degrees celcius I believe, while 5w30 is good for significantly lower and the high end does not suffer much. So it would seem that 5w30 is better overall for the car, since you will never even get close to its specified optimum operating limits.

Nah 5w30 is fine for much lower than 0 degrees C, and the 5w30 goes to just a slightly colder temp. You're right about the high end of the temp range, but there's another issue with 5w30 vs. 10w30.. the larger the disparity between the two numbers, the more chemical additives in the oil.. it's less "pure". Since my manual is an 02, I've pretty much always used 10w30.. it was -10F when I started my car this morning (I have an engine block heater keepin the coolant toasty though.. ), everything was fine. Even after working a 9 hour shift today at work the car started up and was fine with the 10w30, and it had only warmed up to about 5F at that time.

 

[Sveivo]

I have consulted my manual, and also a Protege repair manual, and here is what it says:

5W-30 is good for:
-25F to about 105F

10W-30 is good for:
-18F to "infinity"

 

[Reitrof]

I think most will agree that 10W-30 is higher viscosity. No?



Designed? Where do you get this information? The manual says that 10W-30 is just as good as 5W-30 for a wide temp range.

5w30 covers a lower range than 10w30 and is better when cold no matter what temp than 10w30.

By all means use 10w30, but if if you want better protection at startup and cold temps, then use 5w30.

 

[Reitrof]

I have consulted my manual, and also a Protege repair manual, and here is what it says:

5W-30 is good for:
-25F to about 105F

10W-30 is good for:
-18F to "infinity"

Since the climate I live in is hardly ever above 105F but can be lower than -18F I use 5w30. And for most of the normal temps, 5w30 will get into the areas at startup faster than 10w30.

 

[Sveivo]

Since the climate I live in is hardly ever above 105F but can be lower than -18F I use 5w30. And for most of the normal temps, 5w30 will get into the areas at startup faster than 10w30.

I certainly agree with you here. I was just posting some factual information so that people are not thrown off by "guesstimates."

It also turned out that the 02 and the 03 manuals are different, which, I think caused some misunderstanding.

 

[fonzinator]

I think most will agree that 10W-30 is higher viscosity. No?

You are correct! Thanks for correcting my mistake. Viscosity is one of those things I always have backwards in my mind and I can't seem to ever get it straight. (confused)