Should 5w-30 be used instead?
 

Is it true that everywhere else other than the US its recommended to use 5w-30? Could the lightness of the 5w-20 be a major cause to engine troubles especially due to high temps? I know it'll void the warranty but my new engine will only be warrantied for 12,000 miles.

After loosing 3 engines on 5w-20, I am now using 10w-40.

Please close this thread and have him search... Lol

how would it void your warranty?

5w-30 will NOT void the warranty.
Yes, everywhere except for the US that's the recommended oil weight.

should use 70w90, or glue.

So i hate to add to "another oil thread" but there has been one question that has been on my mind. How exactly can mazda tell what grade oil you are using? Lets say i use 10w-40 and my motor fails, would they really go through my oil, run some analysis, and get a gauge on what grade oil i have? Would they just look at my receipts? Again I'm not trying to scam a warranty claim, I am just trying to figure out if the "risk" is worth it of using a higher grade oil that others have had great luck with.

Im using Valvoline 10-30 on new reman engine right now. Changed it at 2000 and will change it to 10-40 at 3000 (super hot central Tex). 5 is to lame for my area... it has not even snowed here since 1985.

It's just a myth that change of oil viscosity, brand or synthetic voids the warranty. It does not. There is lot of threads on it. If a dealer say it does they lie and need a lawyer to beat them down.

The owner of Royal Purple daily driver is an Rx8... just sayin.:evil_laug

Hows that workin out for ya? And sorry guys about "another oil thread" thought I was being innovative lol. :newbie: