Synthetic 5w30 vs 5w40

MazSpeed3

Member
I was told that those of us who have smoking turbos and are using 5w30 Synthetic need to switch to 5w40 synthetic based on a bulletin thats out there. Can someone advise or confirm. Thanks !!
 
I'm running 5w30 Synthetic now and have been since my first oil change. After I installed the Cobb downpipe and not soon after my car at idle started smoking.
 
running 5w40 does not solve the smoking turbo issue, its hardly even considered a temporary fix. Mazda is supposed to be resolving the pcv but there has been nothing released yet. if your still under warranty take it in to the dealer. It is recommended that the ms3 does run full synthetic its the rotory thats not supposed to.
 
synthetics are synthetics ... they're all the same.

castrol-use-your-dipstick.jpg
 
i heard mazdaspeed 3's aren't supposed to be using synth, i say BS tho....
synthetic oil is available OFFICIALLY in europe along side the normal mazda branded oil

the recommended grade for the DISI turbo engines in europe is 5W40... so there is no reason why it's bad to run this in your engine here for better protection from heat and high engine load
 
I was told that those of us who have smoking turbos and are using 5w30 Synthetic need to switch to 5w40 synthetic based on a bulletin thats out there. Can someone advise or confirm. Thanks !!


i use 5w30 in the winter season and 5w40 in the summer (synthetic). i do not have a smoking turbo issue, though.
 
Getting new turbo next week

Just had my '07 looked at due to the smoking issue. I have used Mobile One 5w-30 the whole time. From what they tell me, the new turbo will be able to deal with the 5w-30 now.
 
The 5w-40 was used as part of a diagnostic procedure, used on some models in a specific VIN range (which was not very clear, IMO).
 
i used mobile 1 and my car started to smoke....then i sitched to penzoil platinum and it stopped. **** if i care why it stopped. lol. theres a likn somewhere in here why our turbos leak. something to do with the factory gaps in the turbo being way to large and leaking oil. i dont feel like searching. goodluck.
 
Ugh!! Another thread talking about this topic..really??

If ur turbo is smoking buy this

http://www.pt-performance.com/showProduct.php?vID=3&cID=4&pID=260

try it out before u take it to the dealership, or start crying because ur car looks like a Pig Roast when its running.

also switch to 5w40 like stated in the eight million threads before this one started..its not going to hurt ur car.. there are plenty of members that have switched over to 5w40 without a single issue..

im 90% sure that doing these two things will solve any issues u have or will have with ur turbo seals... unless ur turbo is a complete POS.
 
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cool....never heard of that part honestly. if this goes in the pcv line then its a release of crank pressure into the intake manifold. if i placed this inline from the crankcase to the intake mani removing the oil from the pressure release then would a catch can be deemed usless afterwards? anyone know an answer to this maybe?
 
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