ja1

Mobil 1 and Amsoil have products that are guaranteed for 20-25k. So why the heck does Lexus recommend 5k oil changes?
According to Consumer Report's chief mechanic, you should go by what the car manufacturer says, and nothing else.
My 2011 ES calls for the common 5k oil change. Lexus still stands by that, but say that engines taking 0w20 have been approved for 10k mile oil changes. Every other car I have is much older than my Lexus, and can do 10k oil changes no problem.

So why? I think part of the reason is that the only fully synthetic motor oil Toyota makes is 0w20. How could they recommend a longer oil change if they do not sell the synthetic that can last for that interval? But the flaw with this argument is that they also say "Engines that recommend 5w-20 or 5w-30 mineral oil, but allow the optional use of 0w-20 synthetic oil will CONTINUE to require 5,000-mile/6-month (whichever comes first) oil change intervals if the 0w-20 is used." WHY?????? Are certain Toyota engines more likely to contaminate and degrade oil? I can not think of any other explanation.

I think it would be interesting, if there is anyone out there that does extended interval oil changes, if they did a lab analysis like the $28 dollar Blackstone Labs test, and posted their results. This guy on youtube ( ) gradually increased his oil change intervals to 35k using Amsoil in his VW, and he says he got to that interval by doing lab tests on the oil and slowly doing longer and longer intervals each time the oil was still fine. Not saying you should do 35k intervals, but 5k just seems so low for a modern car.

ArmyofOne

I change mine in my 02 with Synthetic every 5k regardless. But the 4th gens were slugde prone...so cheap insurance IMO.

GunnyFitz

Amsoil Preferred Member for LIFE!
Use it throughout entire Powertrain in every vehicle I own. No way I'll be dropping my own oil every 5k at my own cost.

ja1

So what interval DO you use GunnyFitz, and which Amsoil line? Have you experimented with different intervals? Oil tests?

GunnyFitz

Since I only have 4900 miles on my RCF I have yet to begin Amsoil treatment on that car. - but have every intention on going with this Signature Line Series at10k
Signature Line

Been using this on my wifes 2017 RX350 since hitting 10k. Now on my Ram 2500 Cummins, that's a different story. Ive been running Amsoil for years and obtained Lab / Oil Tests on for its purity (for lack of a better term) and each time I did it - the reports all come back stating its good to go at 10K Mile Oil Change Intervals. That's using an Extended Interval Oil Filter too. Wish I could lay claim to its use in the RCF, but I just don't drive the car as a Primary. I laughed when they started sending me Lexus Oil Change Reminders for the 10K Mile Service!

RA40

iTrader: (6)

My suggestion would be to have an oil analysis done at varying mileages to determine how well the additive package is performing for that given interval. This will be specific for your car and driving scenario so that you can determine what is comfortable for you. I've done analysis from 4K to 14K miles and selected an interval is reasonable for ours. 5K is the safe margin though for some they may feel that it is a less effective yield for the $ at that interval. YMMV

4g63Rules

My girl's 2011 IS250 has 158k miles on it and changes the oil every 7,500miles - 10,000miles full synthetic 10w30. The car performs flawlessly. It is all highway miles, so I would think it all really depends on driving conditions, stop/go or highway, etc.

Htony

No service reminder for oil change? I just follow service reminder on my car.

abefromansausag

I usually use German Castrol and change around 6k miles or so. Blackstone showed it had plenty of life left but it's more habit than anything now