Hey guys,

I drive a black 99 GS400 which I picked up 4 months ago. I just wanted a show of hands to see if anyone is putting synthetic oil in their cars and using 91 octane?

Some feedback would really help.

 

91 octane is recommended for our car. I dont know anyone that doesn't use at least 91 octane.

I'm using synthetic oil right now.

 

I use Mobile 1 synthetic 5-30wt with K&N filter and 91-92 octane gas only.

 

had mine for only 3mo. 91 octane only, and use castrol regular blend 5w-30

 

Premium gas only all the time. Synthetic oil I use during the cold winter months

 

I have only used 91 octane..

And no, i use regular penzoil 5w30.. Changed every 3-5k, its just fine.

 

I have used premium fuel since new and Mobil 1 SYN since 5,000 miles. The car has 184,000 miles and runs like new. Although I believe you could use a mid grade with VVTI, I would not bother.

 

Mobil 1 10W30 (it gets hot here, else I'd use 5W30) and only 91 octane (or better, depending on area - in Texas, she got 93)

 

Always running 93 octane, except for the 2 weeks or so I couldn't afford it and I use Castrol non-synthetic 5w30.

 

Any conventional 10W-30 for me. I dont think any gas station around me has over 91 Oct

 

I use the cheapest gas possible. And regular pennzoil 5w30 every 3000 miles. 01 GS300 and still going strong.[/I]

 

2008 RX. I use premium gas and synthetic penzoil 5w30. Works great, especially in winter where it can get down to -35F...

 

Why do use the cheapest gas possible? If you meant regular instead of premium then you are actually cheaping out and costing yourself more money..... our engines are high compression engines so they actually need that higher burning fuel since it burns slower etc.... so when running regular you are getting worse
gas mileage

 

that is very true!

if you do the math, and supposing you drive 15000 miles a year and your car averages 20 mpg, the difference between regular and premium gas will only cost you $150...

now, there is no set way to tell how much better gas mileage your car will get by using premium over regular, just know that it will get better mileage... lets say its just 1 mpg better... now, you are at 21 mpg... you just saved yourself 35 gallons in fuel over a years time (still assuming 15k per year)... 35 gallons at $2.50 a gallon is $87.50... so, you have saved somewhere around $63 by running the cheap stuff, over the course of a year...

now, by all means, if a vehicle does not call for better gas, then damn, don't use it, but, if your car requires premium, you are doing it a disservice... plus, if you were to go back to premium, reset the ecu, good chance you'll gain 10-20 horsepower...

 

Though not 10-20 HP.
Only 4 and a bit more torque.Still worth it.
You'll never convince the 87 users.
They spend big $$$ and buy a Lexus and then skimp on octane.
They know more than the engineers.
You can use 87 but to get the best performance and MPG,premium is the choice.