I have been reading contradictory posts everywhere regarding 5w20 engine oil recommended by Mitsu. It appears that it wont protect as well as 5w30 and the only reason why 5w20 is specd is due to CAFE reasons (mileage increase per manufacturer over all the vehicles they sell). Anybody else has this concern?

Will the warranty be voided if 5w30 is used?

 

I don't see why Mitsu will recommend 5W20 if it won't protect the engine that well. IMO, I'd rather go with the manufacturer's recommendation. For one, they designed the engine, and they know better what's the best oil to use.

 

Yeah.....just let it go. If anything bad does happen it's on Mitsu..if you use something else it's probably on you.

 

Yeah thats true but once the odo hits 100k miles, the warranty is off. I might want to keep it for a lot longer than that. Doesnt matter.. I'll probably go to walmart and get Pennzoil Platinum 5w20 synthetic put in with dealer filter. They dont charge much and if I keep receipts, then I should be fine right? Just have to make sure that they dont overfill or underfill. Sounds like a hassle but if its worth the extra protection, then I'll go for it as long as warranty is valid with receipts.

 

Just be careful...I'm sure Mitsu will jump at the chance to screw you!

 

as far as oils go, as long as you use a quality oil, such as havoline, or mobile one is the best insurance you can get.
What you need to be concerned with is not so much the viscosity of the oil, but its breakdown characteristics. (bad spelling I know)

Im no oil engineer, but I have built enough motors, and seen more than my share of them ripped apart, and one thing I have learned is this. Bad oil is bad oil, no matter how big the company selling the **** is.
For instance, Quaker state should never be used for anything, not even for lubing up a squeaky door.
Not to bash on them for no reason, but I have seen to many motors pulled apart after a few runs on a dyno, or the strip, only to find massive amounts of sludge already built up.

There is a reason the MOST high end manufacturers recommend mobile one, and that is because it has some of the highest ratings, and best breakdown statistics of almost any motor oil on the market. To my knowledge there are only two oils that are better. First Shell Helix. Point blank, the best oil on the market. There is none better, there is also none more expensive. Two, Redline full synthetic, not as expensive, but alot more than Mobile1. Great oil, just not that much better than Mobile, and alot more more money.

As far as conventional oils go, I have never, and I mean never seen anything but perfect results with Havoline formula 3. I ran it in my turbo'd civic (making 290hp to the wheels on 14lbs of boost and sunoco 104 fuel) and never had a problem. The only reason I ran it was because I did probably to frequent of oil changes. Not until I fried that motor with too much boost, and not enough tuning did I switch to Mobil. I never had any oil related problems, not one with either oil.

as far as the weight is concerned... You most likely need to be more concerned with the 5 in that 5w20, than the 20. 5 is what the oil is going to flow like when its hot, 20 is what it is going to flow like when its cold. So, if you ask me, the closer you can get that second number to the first number the better you are going to be. You dont want your oil to be too thick at cold temp, nor do you want it to be too thin at operating temp. The 5 in that number is the same whether its 5w20, 5w30. or 5w40. the second number is only relavant for a few short minutes when the oil is warming up, and is really realavant on days the temp is less than say 40 degrees.

You should never have a problem with a lower wieght oil, Mitsu specifies it so that they can run a smaller oil pump, one that doesnt require so much force to pump cold oil through an engine. Not to mention the the tolerances on factory motors are getting just stupid these days, and they need an oil that will flow quickly into each and every nook and cranny, valley and journal, as fast as possible. To thin when hot and the surfaces contact and wear, to thick when cold and the oil just wont flow...

Dont worry about 5w20, mitsu recommends it, and warrents your vehicle for 100000 miles, your good dude.

As for not following the exact recommended oil on changes, I would say that mitsu would cover your claim, should you have one, unless you are getting just stupid, and running like a 20w50 or rotella or something just dumb...

 

Thanks for the reply.

 

sound,

i don't want to sound like a know-it-all by any means, especially since my best wrench-swinging days are long behind me and i'm not an engineer, but, you mixed up the 5w and 20 in your explanation, which was otherwise very informative. we've discussed the same info in several threads in just the last month or two. anyway, the 5w indicates low-viscosity 5 weight all-weather, simply meaning that the oil will flow in cold weather like a thin straight 5 weight oil on engine start-up. the 20 indicates the oil will flow like a straight 20 weight at high temps. before synthetics, noone in their right mind would have contemplated using a 20 weight oil unless you were driving all-year round in temps below freezing. my 2006 manual indicates 5 or 10w-30 where ambient temps are generally below 100 degrees, if i remember correctly, and 10w-40 over that. i would assume, but again could be wrong, that your newer outlanders allow 20 weight synthetics, again at average temps below 100 degrees. if non-synthetic 20 weight is recommended i'd be surprised, but these newer engines do have closer tolerances where thinner oil is sufficient, and has less parasytic drag than higher weight oils at warmed-up engine temps. in my '93 expo with the older 2.4L, i used 10w-40 in winter, and 20w-50 in summer, with regular use of engine flush for at least every other oil change, which was done regularly at around 3,000 miles or at least four times a year. i still own that car and it still runs strong with no oil burning, and passed 250,000 miles. but hey, if mitsu recommends 20 weight, and they're honoring their high mileage guarantee, who am i to disagree?

 

your right, I just mis-stated what I was trying to say.
The new outies manual just says 5-20, no specification for synthetic.

 

use what the engineers recommend. You probably do not know more about it than they do.


'nuff said.