fastnoypi

The downside is that it can be too thin and/or shear down too quick compared to a 30 weight and you spin a bearing.

hypervish

I've used 0W-20 (during the winter) in my RX and my ES. Engine ran just as smooth and quiet as 5W-30. I could not see an mpg improvement, but this may have been due to winter blend fuel.

pilot2

Do you still run 0W20 in winter? What do you run in the summer, 5W20 or...? What brand oil and change interval are you using? THANKS.

RamAirRckt

My friend who works for a Lexus dealer (mechanic since 1989, the first Lexus mechanic in the state) uses 0W20 in his own 98 ES2.

hypervish

Yeah, I've been using QSUD or PP 0W-20 in the winter since December of 2012. OCI depending on how much fuel dilution. Usually ends up being around 3k miles.

Anything other than winter I run PP 5W-30 and now PP w/ PP 5W-30 and change every 4500-5000 miles.

salimshah

As long as the spread in weight covers the specified ambient temperature [printed in owner's manual], you will be good.

Then it boils down to "are the ratings correct?". Personally I prefer smaller spread in weight like 10-30 over 5-40 and shift (higher number in summer and lower number in winter) as needed.

Then there are other equally important factors like Synthetic (which handles the wider range better), cleansing property, price, availability etc.

Salim

pilot2

Forgive me for asking newbe questions, BUT, I assume QSUD is a Quaker State oil, but what is "PP" ? When you say your OCI is dependent on how much fuel dilution--are you having oil analysis done to determine fuel dilution or...? If oil analysis, will you share those reports? Am I reading your message correctly that you have more fuel dilution with 0W20 ? Thanks.

pilot2

Does he use it year-around or winter only?

hypervish

Sorry, I'm used to Bob Is The Oil Guy Forum when it comes to talking about Oil that I start using acronyms.

QSUD- Quaker State Ultimate Durability
PP - Pennzoil Platinum
PP w/PP - Pennzoil Platinum with Pure Plus Technology

I can estimate how much fuel dilution in terms of how many cold starts with short trips. I end up with a lot more fuel dilution in the winter because I tend to warm up the car a long time which is just throwing fuel into the oil, and sometimes the trips are less than 1 mile which isn't enough to burn off the fuel.

I've done a UOA(universal oil analysis) once but decided it wasn't worth the money each time for something that isn't necessary.

pilot2

My manual has no ambient temperature references to when 5w20 or 0w20 would be acceptable--it promotes 5w30. As 0w20 and 5w20 have a smaller spread than the recommended 5w30, then I assume that is a good thing so long as the ratings are correct.

Ratings being equal, It all leaves me wondering, what does manual recommended 5w30 bring to the engine protection party that 5w20 does not?

Salim, what oils and weights are you using?

salimshah

Dont get confused by the spread.
5W30 means any number is valid for this oil as long at it greater and equal to 5 and less than or equal to 30. So this oil will work in all ranges that 5, 10, 15, 20, 25 and 30 would work.

Salim

fastnoypi

Salim, the way this is expressed may cause some confusion and be potentially damaging, IMO.

The number preceding the "W" in an oil weight is the cold temperature tested flow behavior. The number right of the "W" is tested viscosity at full operating temperature (generally accepted at 210*F)

Depending on your individual car's blowby, you can fuel dilute your oil well below acceptable protection and you will need to do more frequent oil changes to maintain protection than an oil with a higher SAE operating temp value. IE. a 5w20 or 0w20 oil will potentially shear down to a 5w10/ 0w10 equivalent over time.

A few more mpg is not worth potential accelerated wear or more frequent oil changes IMO. Stick with what the manual recommends or go slightly heavier, not lighter.

pilot2

Interesting OIL WEAR TEST RESULTS REPORT here that places PENNZOIL ULTRA at the top of the "outstanding protection" list of oils. As an aside, it can be bought for $25.00 for a 5-quart jug--which includes shipping as noted here; is PP or PPw/PP better than Ultra?

salimshah

Thank you for the explanation. It seems my simple understanding of multi-weight oils was wrong.

Salim

fastnoypi

Salim, here is a pretty well written article that might be of interest to you. http://www.upmpg.com/tech_articles/motoroil_viscosity/

For those using a 20 weight oil to attempt to get more mpg, i highly suggest on your personal vehicles to run a baseline oil analysis with the 5w30 stated in the manual and another analysis on your 0w20/5w20 oil if you choose to go that route.
Inform yourselves of any indicated wear and fuel dilution expectancy. Hopefully no red flags of high metal content will surprise you.