Mazda dealership idiot alert.... Im ticked

The 2008 Mazda3 manual says to use 5w-30 if your car has a turbocharger.. or in otherwords - if you have the Mazdaspeed3.
. . . and 5W-20 for 2.3 non turbos.
If 5W-30 is good enough for a turbo, than it's got to be OK for a non turbo ?
Besides the 5W-30 is usually easier to come by.
 
ya, it's fine for non turbos as well. 5w-20 gives slightly better gas mileage, though. basically, the 20 and 30 tell you how high in temperature your oil will maintain a usable viscosity. the higher the number, the higher the temp the oil can withstand. we should use 5w-30 because our turbochargers get a LOT hotter than our actual engines. if you don't need the higher grade stuff, you shouldn't use it unnecessarily, as this will needlessly decrease gas mileage. in other words, there's no reason for a normal honda civic to use 5w-30.
 
Oh yeah.. I wasn't saying 5w-30 only for the ms3. I was just responding to the post that said the old mz3/ms3 manual said to use 5w-20 for the speed3.
 
ya, it's fine for non turbos as well. 5w-20 gives slightly better gas mileage, though. basically, the 20 and 30 tell you how high in temperature your oil will maintain a usable viscosity. the higher the number, the higher the temp the oil can withstand. we should use 5w-30 because our turbochargers get a LOT hotter than our actual engines. if you don't need the higher grade stuff, you shouldn't use it unnecessarily, as this will needlessly decrease gas mileage. in other words, there's no reason for a normal honda civic to use 5w-30.


Just to expand on this:
The first number tells you the viscosity of the oil when cold and the second number tells you the viscosity of the oil when hot. The W tells you it met the SAE Winter or Cold requirements (no it doesnt stand for weight) - if it doesnt have a letter it means it met the SAE HOT requirements

Also as a rule of thumb a -20 oil will have equal viscosity at high temperature than a -30 oil running about 30 degrees hotter (for example the -20 oil running at 190 degrees will have the same viscosity as the -30 oil running at 220 degrees) - this approximation will work between 190 and 260 degree F range... I dont know why for other viscosities the rule of thumb is 20 degree jump (say from a 30 to 40 or a 10 to 20) -
 
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Also as a rule of thumb a -20 oil will have equal viscosity at high temperature than a -30 oil running about 30 degrees hotter (for example the -20 oil running at 190 degrees will have the same viscosity as the -30 oil running at 220 degrees) -

that's a really interesting bit of knowledge. thanks for the insight! :D
 
Here's an interesting article on 5w20 vs 5w30.
http://www.machinerylubrication.com/article_printer_friendly.asp?articleid=518

A paragraph to ponder from the article:

"The best protection against wear is probably a product that is a little thicker (such as SAE 10W-30 or 15W-40) and has more antiwear additives than the oils that support the warranty. The best oil for your vehicle depends on your driving habits, the age of your engine and the climate you drive in, but it is not necessarily the type of oil specified in the owners manual or stamped on the dipstick."
 
So I took mine in for recalls and had oil change done... funny thing my receipt also showed 5W-20 - I went back in and told service rep..the service manager happened to be there and indicated that he had a MS6 and assured me they used 5W-30 but the computer that prints the receipt only had one entry for oil change and would spit out 5W-20 as all other mazda's except the MS6 and MS3 use 5W-30 -

He went and spoke to technician and confirmed it was 5w-30 that was used. Just in case others run into this problem it "may" be computer issue or tech issue - best bet is to ask BEFORE they change the oil....
 
So I took mine in for recalls and had oil change done... funny thing my receipt also showed 5W-20 - I went back in and told service rep..the service manager happened to be there and indicated that he had a MS6 and assured me they used 5W-30 but the computer that prints the receipt only had one entry for oil change and would spit out 5W-20 as all other mazda's except the MS6 and MS3 use 5W-30 -

He went and spoke to technician and confirmed it was 5w-30 that was used. Just in case others run into this problem it "may" be computer issue or tech issue - best bet is to ask BEFORE they change the oil....

lol. My service rep "assured" me that they dont even carry 5w30!! But nonetheless... an interesting development here.lol again.

BTW... no smoking yesterday. I remain optimistic. My wife is headed to the beach this weekend with the kids, so Im going pull the intercooler and see what I find.
 
all they could tell me at my dealership was that they THOUGHT it was 5w-30, but it's ok, cause we use whatever mazda tells us to use...+_+;

so ya, bring your own synthetic 5w-30 next time! oO
 
My dealer -Kings Mazda in Cincinnati- gives free oil changes as long as you own the car. They told me they had no problem with me providing my own oil, so I just bring six quarts of Mobil 1 5W-30 with me. No worries, no hassles.
 

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