Oil Viscosity
the dealership is probably lying about it because the still have a large amount of 5w-30 oil left instock.
I am running 5w-30 mobil1. I am sticking with it because here in the central valley it gets to about 110 and that will fry the engine oil when you are stuck in traffic. 5w-20 is great on start-up especially in cold part of the country. The oil will break down very fast in the summer heats like mine here.
I am running 5w-30 mobil1. I am sticking with it because here in the central valley it gets to about 110 and that will fry the engine oil when you are stuck in traffic. 5w-20 is great on start-up especially in cold part of the country. The oil will break down very fast in the summer heats like mine here.
Lead Lap
Joined: Apr 2007
Posts: 520
Likes: 0
From: Hawaii
Lead Lap
Joined: Apr 2007
Posts: 520
Likes: 0
From: Hawaii
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My problem? I don't have a problem. I'm not second guessing the engineers who set up all the clearances in the engine and designed it to run on 5w-20 oil. You feel better because you're running 40 weight oil, but it is robbing power, using more fuel, and running hotter (check your cylinder head temps, not your gauge - the gauge is worthless for anything but grossly overheating).
I've seen guys who do this lots of times, and their decisions are based on how they feel, not how the engine performs. Your engine doesn't appreciate thicker oil and it is no better protected by 40 weight than it is by 20 weight. If you're giving up 2 mpg, that's nearly 10% less fuel mileage. Doesn't that make you wonder how much horsepower you're losing as well? Why would you want to do that?
I've seen guys who do this lots of times, and their decisions are based on how they feel, not how the engine performs. Your engine doesn't appreciate thicker oil and it is no better protected by 40 weight than it is by 20 weight. If you're giving up 2 mpg, that's nearly 10% less fuel mileage. Doesn't that make you wonder how much horsepower you're losing as well? Why would you want to do that?
using thicker weight oil does NOT mean you have more engine protection....
Pole Position
Joined: Oct 2007
Posts: 234
Likes: 5
From: Vegas
Any suggestions for the HOT southwest area during the summer heat (115+)?
I just put in 5W-20 M1 EP when I bought the IS350 (with 7K miles on it at the time...have no idea what was in it, but better safe than sorry). However, when May rolls around and it starts to get hot as hell here, I'd be curious as to recommendations on weight for the summer months. Stick to the 5W-20 or what? Thanks all.
I just put in 5W-20 M1 EP when I bought the IS350 (with 7K miles on it at the time...have no idea what was in it, but better safe than sorry). However, when May rolls around and it starts to get hot as hell here, I'd be curious as to recommendations on weight for the summer months. Stick to the 5W-20 or what? Thanks all.
Any suggestions for the HOT southwest area during the summer heat (115+)?
I just put in 5W-20 M1 EP when I bought the IS350 (with 7K miles on it at the time...have no idea what was in it, but better safe than sorry). However, when May rolls around and it starts to get hot as hell here, I'd be curious as to recommendations on weight for the summer months. Stick to the 5W-20 or what? Thanks all.
I just put in 5W-20 M1 EP when I bought the IS350 (with 7K miles on it at the time...have no idea what was in it, but better safe than sorry). However, when May rolls around and it starts to get hot as hell here, I'd be curious as to recommendations on weight for the summer months. Stick to the 5W-20 or what? Thanks all.
If so I would switch to 5w-30 max. You are running synthetic
so you can get away with 5w-20 in the summer. Syn oils tend to break down slower (molecularly speaking) less then conventional oil. Thus the heavier weight in the summer months.Your good to go!
^^Lexus recommends 5w-20 under all conditions. The cooling system on the car is more than adequate to maintain normal operating temperatures under normal conditions. If you are tracking your car, you might want to run 5w-30 or 10w-30 Group IV or Group V synthetic since it needs no VI modifiers to meet the 10w-30 specs, but for street driving, the recommended oil is 5w-20 period.
OK, summarizing from posts above..
so, 5W-20 gives better MPG, quicker at startup, but worse for track racing?
5W-30 has better performance for track racing? it is heavier so slower at startup (maybe this is why the gauge is so slow to go up in cold start)
so, 5W-20 gives better MPG, quicker at startup, but worse for track racing?
5W-30 has better performance for track racing? it is heavier so slower at startup (maybe this is why the gauge is so slow to go up in cold start)