so the entire time ive had my car i have been using 5w30 (mobil 1) and today at work i looked it up and it said the tC's require 5w20... sow hat i want to know is, is 5w20 the oil we need to use or is 5w30 ok?

 

Either will do fine. There's been talk about 5w30 being a factor in sludging but I've only read posts that refer to it and not any actual research. 5w20 has become the standard motor oil for Toyota on '06 and up models (like the tC). There's a loooooong post somewhere in here on the subject.

All that being said, I'll be using up all of the 5w30 I've got laying around before I switch to 5w20. The fact that you pay enough attention to your car to know the difference puts you ahead of the general public as far as preventive maintenance goes.

 

There was a TSB that came out after the '06 release indicating to switch the '06s to the thinner oil. That TSB did not apply to '05s however. There are a couple of threads about this. I personally wouldn't want to switch to a thinner oil the way I push my car.

 

Personally, I would stick w a 0w30 or 5w30 oil. The viscosity @ 200F of a 20w oil is only 8 where the 30w oil is 10, which is the ideal viscosity for your engine to protect moving parts, keep oil pressure where it should be and keep the engine cooler via the high flowing oil moving heat out of the depths of the engine.

As long as you follow a regular interval for your oil changes, use name band oil (I am big on synthetics myself) and STICK WITH IT, I see no way a 30w is going to sludge more than a 20w. Lack of proper maintenance causes sludging, not weight

 

A little off topic, but the 08 xB manual calls for 0W-20 or 5W-20. It recommends 0W-20 for fuel efficiency and better cold flowing.

 

so going like.. 10k miles as apposed to 5k miles would cause sludge eventually.. i change mind a little before 5K.. geuss i get to aincous (how the f do you spell that damn word?)

 

Anxious.

I think that many enthusiasts change oil frequently, or even early, because they just enjoy doing it. I know I do. To me it isn't even a chore, it's fun.

 

its like.. it lets you know your car is doing good.. a visual knowing your car is well maintained

 

5W-20's show excellent used oil analyis' over at bobistheoilguy.com. You might want to switch over at the next change for the possible increase in fuel economy of the thinner oil. I personally am going to use 0W-20 which is recommended for the xB.

 

I'm running synthetic 5w-20 in my 06' tC.
Have 30k miles, everything is fine.

Castrol Syntec & Pennzoil Platinum are my favorites.