Hello, I wanted to know if it would be a good idea to switch from the recommended 5w30 motor oil to 5w20. My car is a 06 tC and I know it's recommended to use 5w30 but I wanted to know if I could possibly get some small gains in fuel economy and maybe even hp by switching to 5w20. Right now I use Amsoil 5w30 fully synthetic but I've seen dyno test videos of cars that used eneos and gained hp. I dont wannt to use Eneos's 5w30 oil because it's a synthetic blend. Should I do the switch or should I just keep using the 5w30. The car also has 120000+ miles on it.

 

you could switch. you wont gain fuel economy or hp...the 20 and 30 are just different viscosity ratings. just stick with whatever your engine/user manual says to use.

 

There's a TSB out that all 2AZ-FE engines should now be using 5w20. I think you can find the thread over in tech.

 

5w20 is the recommended oil. . Id switch.

 

05-06 have a different recommended oil than 07+ i think...

 

for the 05-06 motors they did reccomend 5w-30 but now the new toyota standard is 5w-20 so basically if u went to the dealer for an oil change they will be putting 5w-20, which means you are safe to do so

 

i have a 06 tc also and i had to go to the dealer for something and i got and oil change and they put in 5w-20..i would normally do it myself but it wasnt weather permitting....

 

ok thanks for the info guys, I just wanted to be sure before put the 5w20 in. Ill take a look at that TSB in tech too.

 

yup the oil changed for the 06 models, 05's still use 5w30 but the 06 and up changed to 5w20 idk y but wouldn't hurt.

 

I think there was some heavy discussion about how 5w30 produced more sludge than 5w20, but I never saw any solid data on that. The TSB should point you in the right direction, and the fact that you're paying attention means you're well ahead of the curve in my book.

 

IMHO I wouldnt put 5w20 in any car ever, 5w20 might as well be water

 

^ damn i guess this means all tC motors are gonna blow up now!

 

Here's the TSB

http://www.greenhybrid.com/discuss/a..._tsb071002.pdf

If you read carefully it clearly states this:

"The recommended viscosity grade for this oil differs according to vehicle model.
Use the recommended grade specified on the oil filler cap or in the Repair Manual
or Owner’s Manual for each vehicle."

It also lists which 2AZ-FE engines can use 0W20, and the tc isn't among them.

 

for a dd 5w20 is probably fine, but for any kind of agressive driving id never use it, put a bottle in the sun for a few hours on a hot day and feel the viscosity, thats why ill never use it

 

Its seriously not that big of a difference. 5w20 supposedly gives slightly better gas mileage, but it isnt gonna be very noticeable. Dnt knw about HP...If you wanna switch, then just switch....one is thicker than the other, and one burns slower...big deal

 

Hey thanks for the TSB SFTifoso