bam

On the '12 450h, it says to set it to 33 cold psi for the 19" tires. We had ours at 37 and we were getting 29.7 mpg. We recently took our car in for the 5k mile check up and I requested to pay for an oil change on my own dime. I did confirm that they changed the oil with synthetic 0w-20 but it seems that the cold psi was adjsuted down by about 3 psi. After the oil change, I reset all mpg trackers on the car and now it says that we're only managing to get 28.4.

Frankly, I'm a little surprised that Lexus Corp says that the cold psi should be 33. I really can't imagine anybody acheiving their 32 city/28 hwy mpg with 33 cold psi. We were already working to get 29.7 with 37 psi. If anybody is getting 30 mpg combined with 33 cold psi, you must be a magician.

sweetboy02

Me too, I got average ~ 24-25MPH when the tire 36-39 and only 21-22MPH when the tires 32. Always keep them higher to gain to extra miles. Also i feel the car lighter (roll easier with less press on the pedal.

Marqevans

Have their been studies that say raising your tire pressure above recommended has a significant increase in gas mileage? I used to keep my 2010 RX 350 near 35 psi. On my 2012 I'm following recomended 32 psi, but I only have 1,000 miles on it so it's too early to tell.

bam

Although I don't have any specific studies to cite, I would venture to say that it's a known fact that raising the psi increases your mpg. I just didn't think it affected the 450h so easily.

Of course, other factors must be taken into acct when review your mpg but then general understanding is increasing the psi will increase your mpg. Some other things to keep in mind are the type of tires on your car. Nowadays, many tire manufacturers are introducing low rolling resistance tires so there will help. You'll also need to consider what your'e carrying in your car too. The more stuff/weight, the less mpg because that's just more weight the engine has to move.

UCSB

I've been running my 450h FWD in the 33 to 34 range and getting 30 MPG (sometimes higher). But, it is primarily city / suburban driving in town. I don't commute, so no traffic situations. I am considering lowering pressure to improve ride quality. I am using the Dunlops on 19" wheels. I would expect higher tire pressures to be very helpful for gas mileage on the 450h and I may also try higher pressure to see effect on ride quality (I would expect it to deteriorate). My primary concern is ride quality and noise.

EDIT: The 30 MPG is with reasonably hybrid friendly driving. Some work is involved! If I just go with traffic flow, drive in the fast lane and use the car in a normal manner, mileage will definitely drop to 28 MPG (freeway speeds can easily reach 75 around here). On the other hand if I pull all of my hypermiler tricks together, I have seen 34 MPG, 36 MPG and 44 MPG on short trips.

kitlz

I have my tire pressure set at 34 per my SA's advise. She is experiencing excessive tire wear on her RX with Michelins. She liked the Pirelli Scorpion Verdes I have on now so much that she will probably get them for herself.

I can't comment on mileage yet because this is the first time driving the Pirellis in warm weather. They are low rolling resistance tires. One of the claims is increased mileage. But they're also about two pounds heavier than the Dunlops I replaced. Might be a wash.

Cruiter

33PSI cold, 19" Michelin's. Tank to tank now is a tick over 31 but I'm capable of getting better if I keep my foot out of it .

markrivers

Sweet spot of 35psi.
Return is a combined 24mpg on an RX350.u

UCSB

I would be interested in how the Pirellis perform relative to the Dunlops on gas mileage, road noise and ride comfort. I am considering just swapping my Dunlops out for the Pirellis.

Paul B

UCSB, I swapped the Dunlops out when the RX 350 had 300 miles on it and it now has 1225 miles, so I can only give you limited anecdotal evidence on the swap. Basically the Tire Rack folks told me I would double the expected tire life, and I feel the ride is better and the interior noise is reduced. It was apparent to me right after I made the swap.

During the winter months, my wife goes skiing 2-3 days a week and I wanted All-Season tires that would perform good in the snow, although obviously not as well as dedicated snows. The Tire Rack survey of end users for the Pirelli tires rates the snow performance as very good, and the wet performance, which we have some experience with here in Seattle, to be quite good also.

I don't like to compromise on safety, so I made the switch. They are supposed to be a "green" tire and use less material in their make-up as well as being more round and get better gas mileage. I can't comment on that.

kitlz

I hit almost 34 MPG two weeks ago on the drive to work and it probably would have gone higher if I kept going. That's with hills too. Never managed to do that with the Dunlops. Mileage is staying in the 27+ area with eco mode on. I don't take it easy on the gas pedal especially going up the sinewy road near home Handling is superb and more confident. Road noise, well I like my music, couldn't tell you about that Tire pressure stays consistent, no more adding air twice a month. And I do feel a little higher than before. I have about 1,500 miles on them now.

2011RX350

35. It is safer, more economical and avoids low pressure alarms on cool mornings. Gives a little cushion time too if you have one or two with slow air seepage.

Sevn86

Currently set to 32. Want to set to 34 but I'm scared i might start to see uneven thread wear.

MEP7557

I keep mine set at 30-32 psi and I do not have a wear problem.I do have the Michelin's. My RX350 AWD gets what they stated on the sticker. Since the day I took delivery I have never reset the overall mpg and it is at 20 mpg. I do about 33% or less highway driving.

wa3cuj

I use to run my Dunlaps at 2 psi over recommended. As they got more mileage on them the tire noise picked up so I went back to the recommended psi and the tire noise has gone away. In the summer I generally run around 29-30 mpg with my best tank being 32.9.

I saw a greater difference in mpg at highway speeds using the higher inflation.

I will start tire shopping before this winter get here.