Originally Posted by LexsCTJill

This is a long debate.

I only have personal experience with the 4.7 engines. Our past LX470 required premium fuel whereas our 4Runner with the identical 4.7 (Tahara built) V8 stated regular fuel is fine, but for optimal performance, use premium. We have two failed cats on our 4.7 4Runner at just 110K.

The engine might be the same, but the exhaust system and 4WD are a bit different. The weights are different as well. The LX is at the very top of end of weight and put the most stress on the 5.7 for sure. I do not think the Toyota 5.7 is rated for SAE J2807spec numbers. For example, my 04 4Runner was not rated at the SAE spec, while the 06 4Runner was. So the 381hp for all Toyota models is a bit misleading IMO.

I can't imagine the Toyota engineers made a mistake and put the premium fuel disclaimer in the manual.

Here is an interesting POV from IH8MUD:

Originally Posted by AJT123

Thanks, Jill, for all of this. Those are fair points, but even at 6k lbs plus I don't think the V8 is overtaxed, at all. The last gen LX was, but not this one. I've seen 0-60 times as fast as 6.5 seconds for the 570, and people on here have told me that with regular driving the truck just loafs during regular driving not working/revving hard bc 90% of torque is available at 2200 RPM.

I don't see how the exhaust and 4X4 would have anything to do with it.

Originally Posted by AJT123

Thanks, Jill, for all of this. Those are fair points, but even at 6k lbs plus I don't think the V8 is overtaxed, at all. The last gen LX was, but not this one. I've seen 0-60 times as fast as 6.5 seconds for the 570, and people on here have told me that with regular driving the truck just loafs during regular driving not working/revving hard bc 90% of torque is available at 2200 RPM.

I don't see how the exhaust and 4X4 would have anything to do with it.

Originally Posted by AJT123

Actually it's a $90,000 vehicle.

And no, I won't be using it just to get groceries. I'm buying it for the solidity, reliability, the luxury, and the capability to get through any blizzard on my regular trips to upstate New York to see inlaws. It can get bad fast when you're in bmfk Ohio or Penn and bad winter weather hits.

I will also be off-roading the hell out of it, as long as I won't damage the paint. There are tons of places to go mudding/off roading around here.

And yes, it's a waste of money using premium, I'm pretty sure. Lexus wouldn't sell a vehicle made for regular gas, it would throw off the "premium brand" pretense. The motor is completely identical.

Originally Posted by coolsaber

As they say to each his/her own. If you own a vehicle in warranty, then yes, KISS and just put in premium. However if your buying used with or without warranty, or you really dont mind the going back and fourth to prove that the gas tier caused them to deny your warranty claim, then by all means.

This thread topic pops up in every forum, and both sides bring out expert witnesses to the fact, but at the end of the day, do whats best for you, and deal with the benefits or consequences lol.

Originally Posted by cb1111

That's so true - with one minor exception. Here, you have the comparison to a nearly identical vehicle/engine that the same manufacturer says requires regular.

I'd opine that the majority of the posters on all of the forums that this comes up in pull up to the "Regular" pump when it comes to their wallets.

That doesn't mean that there isn't a place for premium gas and there are plenty of cars that require (or run better) on premium - I don't think this is one of them.

Originally Posted by AJT123

Agreed. My LS430 feels a bit sluggish without premium. You can tell a difference, although I still don't think it's doing any damage.

Originally Posted by cb1111

It is unlikely that you're doing any damage unless you have continual pinging.

Originally Posted by LexsCTJill

You can always hear engine knock. And the idea that Toyota engineers are wrong to require it or the idea that it is a marketing thing is just absurd

Originally Posted by hankinid

I have yet to hear knock on neither the '01 LX nor the '13 200 series. Knock sensors feel the beginnings of knock and retard timing accordingly.

Originally Posted by cb1111

It is unlikely that you're doing any damage unless you have continual pinging.

Originally Posted by AJT123

Never have heard a knock. I think it runs just fine on regular, but you can tell a difference in response when you boot the gas..

Originally Posted by LexsCTJill

That is because you are not putting premium. My 4Runner 4.7 has a bit more power and feels like it has more torque with. Premium. Manual even says for optimal results use premium.