Tittle says it all, to make a long story short, I took my 07 AWD LS in for a free service, two days later(today) I noticed the cervice sticker on the windshield that said they have replaced the oil with 10w30. So I quickly took note of the manufatures spec that said our cars use 5w20 and got on the phone with the dealer's service rep who said " sir I have talked to our Certified technician who recommends 10w30 for local weather reasons(eastern NC). So I then replied, what do you think has a greater value of importance: the techs opinion or the manufacturers recommendations? hethen gave up on the argument and told me I can have it replaced again, but he strongly recommended what the tech rep said.

What do you guys think? should I go by what the dealers tech says or do what themanufacturer recommends?

 

I wonder why there should be an argument in the first place. Dealers doing maintenance on their own cars ought to know better. Of course they should go by the manufacturer's recommendation. At least he could have informed you that he was not going by the 5w20 before he did the oil change.

 

If you let them do the service at the dealer then what they choose to use is on them.

 

I gave Mitsu NA a call today on my lunch breack and they told me that the dealers should be going by what is recommended in the manuals not by a technicians opinion, this is more thanenough for me to go back and get my oil replaced at no charge for 5w20.

 

Yes, I just talked to my local (long story) service manager, and MMA about this very thing. According to them If you take note to what mitsubishi calls heavy driving, where it reccomends changing the oil and filter every 4000miles, it has the exact same "reasons" as every other manufacturer who calls that normal driving.
As for the 10-30. According to MMA, 10-30 motor oil will have no negative affect at all on the motor. All dealers are either using that, or 5-30 for factory replacement oil. No worries, I am chaning mine tonight when my car gets back from mitsu, and i am going to use a Mobile1 5-30.

 

I thought I read some were in the forums that mitsu recommends 5w20 on our cars because its what works best with the oil pump on our vehicles, I may be wrong, I'm just quoting something I read.

I know there are threads on this here and they all have said to stick with 5w20, is there any reason to use something else?

 

On my first oil change, I'd go for the 5W20 as well. If the dealer can use either, why not go with what the manual recommends?

 

If you are going to bring your ride into a Mitsu dealer for service then let them do their thang...whatever they use is on them.

 

I agree... if mitsu does it, then its on them, Me, I am going by expererience, and what the book says, thats why I am going the 5-30 route. not that there is anything wrong with either, just thats what I am doing. I dont really care for 10-30, think its too thick, but I also think 5-20 is too thin. (this from the guy that runs 0-20 mobile1 in his highly built Si) i know I know, but hey, if its good enough to last through 320k miles on my bro-in-laws chevy, then 5-30 is fine for my mitsu. (guess what I am saying is that if it didnt cause any harm, and helped him make it that long in a chevy, and you know it was the oil, cause no chevy ever runs that long without help from god, then it should be fine here.)

 

I wouldnt worry too much about it, if the engine fails now or later and it can be proved it was due to the oil, your Mitsu dealer would have to pay to fix it, as on file it will say they had been using 10w30.