BobsGX

I was just looking at a TSIB that Lexus says they will be installing 5W-20 oil in the engines at the factory and that it is approved for all 2006 vehicles with the GR, JZ, MZ, UZ and VZ engines. The GX uses the UZ engine. I plan to stick with the 5W-30 oil as is printed on the oil fill cap. They made the changeover in February 06. Has anyone here with a March or April built GX noticed if it says 5W-20 oil on the oil fill cap? Just wondering.

flipside909

wow interesting find. 5w20 for the JZ and MZ series? For the MZ series...that's a little scary to me esp. here in CA climates. I use 10w30 for my 1MZ-FE V6 Solara all the time and 5w-30 for my 2JZ-GE IS300.

TunedRX300

I have been using Mobil 1 0w20 (discontinued) and 5w20 for one and half years and 25834 miles in my 1mzfe RX300. The 20 weight oil holds up well considering 1mzfe is known to chew oil up.
The 5w20 I used for 8200 miles is changed this weekend, it is clean and not thickened. I am sending a sample of M1 5w20 to get an oil analysis report and expect to have a good result in term of TBN and low iron, copper and lead particles counts.

5w20 is introduced by other automakers for CAFE mainly for an average of 0.5% mpg gain, however, there is no sacrifice for engine reliability. In many cases, thinner oil extends engine life more than thick oil does because 1) higher flow lubricates engine better at startup, when most engine wear occur 2) higher oil flow cools engine better at operating temperature
At operating temperature 100º C, viscosity of M1 5w20 is 8.8 cst, a mere 1.2 cst difference to the ideal viscosity of 10 cst for lubrication. However, at startup temperature of 40º C, the difference between 5w20's 48.3 cst and 5w30's 64.8 is 16.5 cst. Both are two thick to lubricates engine well but 5w20 is better than 5w30.
http://www.mobiloil.com/USA-English/...bil1_5W-30.asp
http://www.mobil.com/USA-English/Lub...il_1_5W-20.asp
The difference is even bigger when one uses 10w30 and starting temperature <40º C.

Just FIY, Formula 1 cars that run at 15,000 RPM and higher use straight 5 and 10 weight oils

mkool

So do you know when does 5w-20 commin out to ratail store?

rxdriver

5W-20 is out there in stores. I know that Honda has been using it for a while now.

TunedRX300

Honda made the change around 2001. Similiar to what Toyota is doing now, Acura/Honda did not make a single change in powertrain design but made 5w20 as the official recommended oil. For example, 2000 Acura TL calls for 5w30 but Acura changed to 5w20 for the 2001 model, even though the new model has the same J32A1 engine and 5 speed sequential shift auto transmission.
There is a laundry list of automakers already made the change, such as Honda and Ford. I believe if your cooling system is good enough for your driving style, there is no reason to be concerned about reliability.

Lexmex

Castrol has a German blend that is a 20 and a lot of tuning friends seem to like this stuff when they can get their hands on it. Does not surprise me one bit that some manufacturers are using this stuff with their newer models instead of a 30.

Mobil 1 is still tops with me for engine oil.

BobsGX

Ford has also been using 5W-20 since 2001. When I had my 2003 Mustang SVT Cobra, it called for 5W-20 oil. Pennzoil, Quaker State, Castrol, Valvoline, Mobil 1, Amsoil and Redline are some of the companies making 5W-20 oil.

TunedRX300

I found this interesting oil analysis report posted back in 2002.
http://theoildrop.server101.com/cgi/...c;f=3;t=000141
The guy who owns a Toyota 3.0 V6, most likely a 1mzfe, did a virgin oil analysis of Toyota bulk oil and compare it to two used oil analysis reports in his engine after 200 and 1500 miles.
It turns out Toyota's mineral based 5w30 oil thins out to a 20 weight oil before the first tank of gas is used up. I believe synthetic 5w30 will hold up its viscosity better but looks like owner who change oil at Toyota/Lexus have been driving around mostly on 20 weight oil anyway.

Pheonix

Guys keep in mind, Lexus/Toyota/Scion oil comes from ExxonMobil in Mexico.
AFA the v6's go; mobil1, across the board against similar oil, kills about everything when it comes to breakdown / engine wear / UAO's left. Which is also why Wall-mart Super-tech has been doing so well despite being cheap. Along with Toyota oils in Toyota's - It's all ExxonMobil!


Anywho: I haven't been able to tell any differance on my engine running 5 quarts of 5w-20, but whatever. LoL!



A discussion we had about the swapover a good while back on loc
http://us.lexusownersclub.com/forums...&gopid=200099&

dshahs420

[QUOTE=TunedRX300]I have been using Mobil 1 0w20 (discontinued)


The 0w20 is back in the market because all the hybrids are calling for it so mobil knew that there is money to be made with 0w20 so they re-released it and seeing the VOA on this oil its an awesome oil to use!

TunedRX300

[QUOTE=dshahs420]Could you link me to a VOA of the new 0w20? 0w20 I used was a GF-3 oil, Mobil web lists it as a GF-4 but I have not seen it in store yet.

koolaidman

some1 said 0w20 is discontinued. honda in some aplications use it. ie to fix a problem.
honda/acura and ford have been using 5w20 since 2001. and if some1 can give me the tsb number id like to check that out

dshahs420

0w20 is not a discontinued oil, its the in-thing. Its the fad now. With escalating gas price and popular demand for hybrids, they all spec for 0w20 oil to meet the CAFE numbers and improved gas mileage. I personally would use 0w20 since all the UOA's on 0w20 oils especially mobil 1 are really good!

dshahs420

[QUOTE=TunedRX300]Sorry, I have not seen VOA's of the new gf-4 rated 0w20 mobil 1 oil online. My friend had an analysis done and he shared with me and it looked good....good anti-wear additive numbers, high calcium and sodium but the moly went down, presuming to meet the SM requirements.