5W-20 or 0W-20 Back-Spec
#1
Lexus Test Driver
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Have any of you tried a 0W-20 or 5W-20? I've seen the chart below, posted a few times over at Bob Is OIl Guy and am wondering if it's legit. Is the RX300 really back-speced for it?
#2
Pole Position
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I used 0-30 Castrol Oil like Lex Mex has and it worked great in my RX300.....I dont see any reason not to use the 0-20 and see if your fuel economy improves....
#3
Lead Lap
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I'm using 0w20 in my '08 IS250 now, I notice a big difference between 0w20 and 0w30 I was previously using. Car has more power, it definitely feels like it takes less work for the engine to get the car moving. I did see an increase in my avg. MPG's. I went from about 330 - 340 till the gas light came on to 390 - 400 miles to a tank now. For me definitely worth it!
#4
Lexus Test Driver
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I'm wondering if it's too thin for the 1MZ-FE though. I've ran 0W-30 but that's really no different from a 5 weight, the only difference is at startup and then the 0W becomes a 5W anyways.
#5
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Look at the chart, I interpret the three dots and representing the three different RX's at the top of the chart. The RX 300 is the RED dot, the 330 is the BLUE dot, and the 350 is the GREEN dot. Thus, it does say the 300 CAN run with 5-20w or 5-30w. I've run the 0-30w in winter, but mostly run the 5-30w. I have an 04 Acura 3.5 6cyl that requires the 5-20w. My thinking about the 30w vs the 20w would center on the heat in the geographic region the RX300 would be running in? I'd likely run the 5-20w in the winter, then the 5-30w in the summer months. Anyway, the chart looks like a range for the different year models or RX. What do you guys think?
#6
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Look at the chart, I interpret the three dots and representing the three different RX's at the top of the chart. The RX 300 is the RED dot, the 330 is the BLUE dot, and the 350 is the GREEN dot. Thus, it does say the 300 CAN run with 5-20w or 5-30w. I've run the 0-30w in winter, but mostly run the 5-30w. I have an 04 Acura 3.5 6cyl that requires the 5-20w. My thinking about the 30w vs the 20w would center on the heat in the geographic region the RX300 would be running in? I'd likely run the 5-20w in the winter, then the 5-30w in the summer months. Anyway, the chart looks like a range for the different year models or RX. What do you guys think?
Last edited by artbuc; 02-21-12 at 02:51 AM.
#7
Lexus Test Driver
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Don't think so. I interpret the chart as showing all 3 RX models in the same group. If one of the RX models needed a different spec it would be in a different column. Look at the GS group which has 5 models. Really no connection between number/color of dots and particular model in the header.
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#9
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I've seen a similar chart before, might have been from Europe, but also remember reading about 1MZFE motors and using a W20. I remember seeing this when hearing about W20 and the 2UZFE 4.7L V8 in our 2006 4Runner. I have run W30 and W20 in that vehicle and can run it out to 10K, but the vehicle still has just over 50K miles on it, still young.
I'd still run a 5W30 or 0W30 (like Castrol Syntec).
If I were going to try a 0W20 or 5W20 I'd look at Amsoil, Redline or Royal Purple, very good in my opinion on those weights. Even Mobil 1 does a very good job here, too.
However, I'd keep an eye on the mileage.
I'd still run a 5W30 or 0W30 (like Castrol Syntec).
If I were going to try a 0W20 or 5W20 I'd look at Amsoil, Redline or Royal Purple, very good in my opinion on those weights. Even Mobil 1 does a very good job here, too.
However, I'd keep an eye on the mileage.
#10
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Talked to a friend who has worked for Lexus since 1989 and he hasn't heard of this document. I have him digging to find any authenticity on it. I am curious....
I did switch to 5W20, and have seen some mpg improvement. I can't complain so far.
I did switch to 5W20, and have seen some mpg improvement. I can't complain so far.
#11
Lexus Test Driver
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Let us know what he says. I still haven't tried the 20 weight yet. lol
#12
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This is what he says, but I send him the document to look at and see if he can figure out the authenticity of it
Originally Posted by Lex
I know of NO such document. I searched and don't come up with one. I have been using 0W20 Synthetic in my 98 ES300 for 3 years now. My car has 212,000 miles on it and runs like it is brand new. It also gets 32.2 MPG on the Expressway at 68 MPH.
#13
Lexus Test Driver
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Hopefully he can put an end to the debate of whether or not this is authentic.
#14
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My GS400 does and it works perfectly fine. My mpg did bump up an average of 1.5-2, I have to calculate it to be sure, but so far it as been noticeable over the last 3000 miles, never once getting down to 5W30 mpg levels.
I won't go back....
I won't go back....
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#15
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I recently purchased a low mileage RX300 and was provided all the prior service records. I noticed Lexus was using GTMO 5W20 for the oil changes. Anyone tried 0W20 --what could be the downside to its use?