Fuel Type for RX 400h
Driver School Candidate
Joined: Mar 2016
Posts: 5
Likes: 0
From: Arkansas
Our 2006 RX400h AWD (135,000 miles) seems to get the same mileage ~26.4, on 87-93 octane. However, when using 91 Octane with no ethanol , it goes up to 27+ which is understandable since ETOH has less BTUs per volume. This is all with gentle driving. I expect the highest performance (acceleration) would come from 93 octane with 10% ETOH.
Lead Lap
Joined: May 2012
Posts: 441
Likes: 2
From: mo
You guys are going to shorten the life of your engine by not using the correct gas.
The gas grades combust differently.
28MPG is what you should be getting on the rx400h even without driving efficiently.
The gas grades combust differently.
28MPG is what you should be getting on the rx400h even without driving efficiently.
Last edited by theory816; Feb 12, 2017 at 01:21 PM.
Driver
Joined: Jun 2017
Posts: 74
Likes: 3
From: Arizona
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Driver School Candidate
Joined: Jul 2017
Posts: 17
Likes: 0
From: South Dakota
We've had our 2006 RX400h for about a month now, and didn't think much about fuel octane until recently. The manual says, "Select Octane Rating 87 or higher. For improved vehicle performance, the use of premium unleaded gasoline with an Octane Rating of 91 or higher is recommended." From that I figured 87 (10% ethanol blend) was ok, and was getting between 22-23 mpg mixed driving, but mostly around town, and babying it. I thought I'd try premium, and put 93 in it the last two times I tanked up; it's now averaging 25.6, even with some more "spirited" driving. I was always pretty skeptical whether octane made much difference, and have rarely seen much difference in other cars that I've owned, but apparently these things like the good stuff. I need to run some numbers to see if it's worth the extra 30-50 cents a gallon to get an extra 3 mpg.
Lead Lap
Joined: May 2012
Posts: 441
Likes: 2
From: mo
The gas cap says in large letters: PREMIUM FUEL ONLY.
Racer
Joined: Mar 2011
Posts: 1,817
Likes: 229
From: wa
Maybe they simply use door from RX350?