Rx400h Battery Recharge?

[zoomjay]

My wife and I just purchased an 07 Lexus RX400h with about 65,000 miles. This is not the first Lexus we have ever owned although it is the first hybrid. Car runs great (although we are not thrilled with the premium gas required - a little "oopsie" after the fact). Question is on the "hybrid" or drive battery.

When we are driving the car the battery NEVER shows beyond 3/4 charged - no matter what sort of driving you do. I also understand that the battery pack is warrantied for 100K miles OR 8 years (just expired: darned). Is a 3/4 charge the most we can hope for or are we likely to be looking at bad cells?

Thanks

[zoomjay]

btw, in case I am not clear... I am talking about the large HV battery in the back of the car - not the 12V battery under the hood.

[RX400h]

Are you sure you have to use premium? We can use any grade in our 2006. You lose a small amount of power but for many the gain is not worth the cost.

Regarding the batteries: We find that the display shows fully charged after heading down a hill that is a couple of miles or more. During normal driving, the charge is not full. (especially when I see an X5 or Cayenne!)

[zoomjay]

Our book (and gas label) pretty clearly calls for 91 octane - which around here is premium (choice of 87, 89 or 93). I think my wife "cheats" a bit and goes medium grade some of the time.

[lenore]

The battery indicator as said above is usually not showing completely charged, unless going down hill. As for the fuel, just as the RX330 and RX300 requires premium, however over the years many have posted that they used regular. The engine is computer controlled and will change timing to account for the regular fuel. On the old RX300 many experienced pre-detonation when putting under heavy load. I would be concerned more about the knock sensors. But quite frankly you will probably be fine.

[texanboy24]

I just bought a 2008 lexus rx 400. I am so happy!!! I want to know how long have you heard of these SUV's lasting? I also want to know whether I should get the warranty.

[katzjamr]

Lexus developed the main traction battery to last the life of the vehicle. That meant keeping the charge of the battery never too full, or letting it go too low, that is why you rarely see all the full bars on the meter that is normal, and it is normal for it to start charging itself with its own generator if you go to two bars, only when the ignition is on of course. Premium gas gives you more power but also more mpg so the extra cost is covered by the increased gas mileage and the engine in your model was designed for premium. It takes two or three tanks of premium to consistently produce the best mileage, driving, ac use and the ambient temperature all factor in to this. Since the main battery is more efficient in warm weather there is better mpg on all grades of gas in the summer rather than the winter. I have had mine new since 2005 and it is the best vehicle I have ever owned.

[texanboy24]

Have you had any problems with the vehicle? How many miles do you have on it now?

[RX400h]

Our 2006's owner's manual states:

Select Octane Rating 87 (Research Octane Number 91) or higher. For improved performance, the use of premium unleaded gasoline with an Octane Rating of 91 (Research Octane Number 96) or higher is recommended.

Pump gas octane is (Research Octane number + Motor Octane Number)/2

Obviously, Research octane is a number that is higher than pump gas octane, so our RX400h does NOT require high octane. We've been running either regular (colder months) or mid-grade (warmer months) for more than 10 years and have never had any pinging, whatsoever. Ambient temperature does make a difference. Cooler = more power.

Texanboy,

We have almost 100,000 miles on our RX400h and have never had any issues of significance. I had to inject some powdered graphite in the ignition key hole, but that's it. Our water pump gasket needed replacement at 92,000 miles or so, but that is more maintenance than a reliability deficit. 12V batteries last 5-7 years here in southern CA. We are very glad we selected this vehicle - the most reliable we have ever had.

And over the years, we have saved many thousands of dollars in fuel cost with our average fuel consumption of 25-27 MPG.

[katzjamr]

137,000 miles oil changes every 4 to 5K, very reliable, brakes last longer, had the dealer do all maintenance but we have a good one south of seattle, we talk about what is really needed and what is 'extra'. only failures were radiator, water pump and front right wheel bearing all covered under warranty or extended warranty. best vehicle I have ever owned.

[texanboy24]

How much did it cost to fix that?

[dbuckius]

The horizontal bars on the battery sometimes showed light green, instead of blue.  What does it mean.

 

thanks

[pj8708-old]

On 7/16/2015 at 9:09 PM, zoomjay said:

Our book (and gas label) pretty clearly calls for 91 octane - which around here is premium (choice of 87, 89 or 93). I think my wife "cheats" a bit and goes medium grade some of the time.

Hi there!

This question comes up more times than the morning Sun. As Lenor has said, It used to be a requirment that only Premium,(91 octane) was approved for purposes of warranty coverage. Since around 2013 the Owners Manual indicated that the use of regular (87 octane) was approved, and you could choose either products without any difficulty. When we bought our 2013 ES 350 and our 2013 RX 350, I decided to try using only 91 octane. That has been about 2 1/2 years. No problems, no ping.

 

Now with Petrol so cheap, I've changed to 87 octane with no problems and still with-in the warranty demands. I don't notice any difference with the two, but I don't do much highway driving so it is difficult to judge any difference in mpg.