So, do we still change oil athe manufacturer’s published interval: 10,000 miles, or changearlier such as 7,500 miles?
What ever lets you sleep at night.
Saw a video from a mechanic who said their 10k oil change interval was too long.
To help them sell vehicles a little sooner?
(Our 2016 RX350 is at 362k with no discernible oil consumption.)
Toyota went from 5K intervals to 10K for oil changes after we picked up the 2010 Prius in July 2009, oil changes done every 5-6K at their suggestion, we’ve been following these guys lead for 30yrs now with no problems.
It was available in 2021. Lexus chose not to use it
I like your post. But this is the part that I don’t think is true. All that matters is keeping the oil flowing and below a certain maximum viscosity at low temperature. Minerial oil has a transition temperature where it transitions from the cold rating to the warm rating. During this time the temperature versus viscosity graph flattens out a bit. Synthetic would have less of a transition point. If someone using straight SAE 30 oil has a minimum starting temperature of 40F, and someone in a cold climate uses 5W30 and has a minimum temperature of -10F, the viscosity of 5W30 in the cold climate could be higher than the user of SAE 30 in the warm climate ever becomes. So the SAE 30 40F start can’t be worse than the 5W30 -10F start. Using 5W30 in a warm climate could still help reduce the time needed to for the engine to warm up and have full power though. The reduced ability of 5W30 to handle overheating and neglected oil changes just isn’t worth it though.
A good synthetic oil can probably handle that. But a 10k oil change in a city car that has an average speed of 15 MPH is 667 hours between oil changes, which is huge. What is the severe duty oil change interval for the vehicle that specifies 10k mile oil changes?
I don’t disagree with what you have said here, but I think I am seeing it from a different perspective. I was a kid of the 50’s and lived in Vermont. I wasn’t that interested in cars at that time. My dad worked construction and took his car to a mechanic.
My grandfather was a fireman and did all his own work on his cars and some of the maintenance on the fire trucks. I do remember him changing to 10w oil in the winter and 30w in the summer. In the spring and fall, he would sometimes use 20w. Back in those days, you did or had someone do an oil change and lube every 2 months or 1500 miles. Also oil was referred to as W or weight, not grade even though grade was technically correct.
In the 60’s I was a teenager living in Southern California. Dad used 30HD year round. My grandfather used 20HD in winter because he had a night shift job where it got colder than on the coast. We called it HD because it stood for high detergent, or at least thats what I thought. There was 30ND which stood for non detergent. So I know that in a climate that never goes below 40 degrees you can use 30w oil year round.
The multi weights were coming out about then, and as I got closer to getting my first car, I got a lot more interested in them. It was a log time before I found out that the w in 10w30 stood for winter and not weight. I was a little confused as to why the w was in the middle.
Keep in mind that while we used “straight weight” oils back then, most of those stone age engines were lucky to make 100k miles. I call them stone age motors because they were machined with various types of stones. Because of that, tolerances were harder to control.
Modern engines machined with carbide and diamonds have closer tolerances and while they may run on 30HD, a multi-weight (pardon me, grade) is much better and they will last longer on it. With oil change intervals as long as a year, switching grades between summer and winter is not practical anymore.
If you want 20 weight oil, buy 20W-50 is is a 20 weight oil and acts like one when cold , but has enough viscosity improvers in it that it is the same viscosity as 50 weight when at operating temperature.
Just found this: $76.99 at Walmart.com
Can you elaborate? My father was a machinist and tool and die maker from the late 40s to the early 90s. CNC machines were showing up in the shop in the late 60s where he worked. He often talked about the early days of CNC machines in the shops where the guys on manual engine lathes and mills had to fix the mistakes coming off those production lines. The only “stones” being used were for final honing operations and weren’t actually stones per se. Hones are still used today for final finishing even with modern CNC machines although often constructed using more modern formulations of abrasives.
Back in the day of manual machining in production environments, tolerances were checked with go/no go gauges. Even small shops today have some type of CMM.
But it’s NOT. And that’s the problem.
TOYOTA OWNERS! Please NEVER Do THIS to Your Toyota! - YouTube
I know certain Toyota engines, like the 4-cyl in the RAV4, used it for their 2019 models.
The Mobil1 site states that Honda, Lexus, and Toyota began specifying it for selected engines in 2018.
Thank you.
Our 2021 RX350 specifies 0W-20.
Walmart says not in store but I found 0W-16 on line.
For petes sake , just use what is called for .
He said it was serviced at the dealer at 10k miles. He said the dealers are known for using the cheapest oil they can get, which would be non synthetic 5W20 in this case. It breaks down in to 5 weight oil after about 5k miles and leaves sludge everywhere. Some oil passages were clogged. The oil rings were frozen. Factory fill is 5W20, but that’s break in oil that gets changed right away.
If it had been serviced with synthetic 0W20 or SAE 20 (non synthetic) at 10k miles this wouldn’t have happened. More frequent oil changes would still help though.
But 50 is not compatible with variable valve timing, and the fuel economy benefit of thin oil is lost. If oil changes are neglected, it will still break down in to sludge and clog oil passages whereas pure SAE 20 oil won’t.
My OCD (Oil Compulsive Disorder) does not allow that.
(Am using 0W-20)
![](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/thewonderful90s/48/29584_2.png)
be non synthetic 5W20 in this case. It breaks down in to 5 weight oil after about 5k miles and leaves sludge everywhere. Some oil passages were clogged. The oil rings were frozen. Factory fill is 5W20, but that’s break in oil that gets changed right away.
If it had been serviced with synthetic 0W20 or SAE 20 (non synthetic) at 10k miles this wouldn’t have happened. More frequent oil changes would still help though.
You know this how? As for using single weight non synthetic SAE 20, that’s NUTS, besides likely impossible. The only one I found was non detergent, meets ZERO specs for a modern car.
![](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/48/862_2.png)
As for using single weight non synthetic SAE 20, that’s NUTS, besides likely impossible.
Lucas seems to make it. https://lucasoil.com/pdf/TDS_SAE20Break-InOils.pdf
I would not recommend that racing break in oil for normal use.
![](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/thewonderful90s/48/29584_2.png)
Lucas seems to make it. https://lucasoil.com/pdf/TDS_SAE20Break-InOils.pdf
Unfortunately, it’s pretty clear where it states:
“Not recommended for passenger cars requiring API service oil.”