Tire Pressure?

[knik]

The door jamb of my ES300 has a plate that indicates proper tire pressure is 27 PSI. comments anyone? :huh:

[Lexusfreak]

That's too low for me.....I keep mine at 34 PSI.....I find that gives a pretty good balance of ride, handling, fuel economy & even tire wear. 27 PSI is too soft imo. :)

[Punk In Drublic]

Mine's at 34 as well.

[bostonsnowboarder]

That's too low for me.....I keep mine at 34 PSI.....I find that gives a pretty good balance of ride, handling, fuel economy & even tire wear. 27 PSI is too soft imo. :)

I suppose there is quite a bit of personal preference involved here.

I have an 05 ES330 with 17 inch rims and my door jam tire pressure is listed at 30.

However, I just realized (after 2 months of owning the car) that the dealership had set my tire pressures at 35. I am going to ask them the rationale for that.

At 35 PSI, I found that the handling was nice and taught (usually people complain about the lexus ES handling as the biggest complaint) but yet there was more road noise than I expected and going over the Boston potholes this spring was occasionally painful.

SO, I have dropped the pressure down to 30 and I like it better. The ride is smoother, quieter, and going over potholes is more comfortable. The handling is a bit worse but that's ok with me.

I would never drop my pressure LOWER than the door jam pressure though. They say that doing that can put you at risk of premature failure. But you can go higher a bit if you want (but of course dont exceed maximum listed pressure)

[Tyler121]

i try to keep mine at near 40...but then again im goin for pure gas mileage.

[bostonsnowboarder]

i try to keep mine at near 40...but then again im goin for pure gas mileage.

How much of a difference in gas mileage would it make going from say 30PSI to 40PSI?

At 35PSI i was getting about 18mpg city and 28mpg highway. I will now calculate it out at 30PSI for a while.

[Lexusfreak]

Let us know your findings at 30 PSI.

[mburnickas]

i try to keep mine at near 40...but then again im goin for pure gas mileage.

I have been doing the same. For me, the sticker on the door means jack <you know what>. THe sticker does not know what size tires you have.

[bostonsnowboarder]

i try to keep mine at near 40...but then again im goin for pure gas mileage.

I have been doing the same. For me, the sticker on the door means jack <you know what>. THe sticker does not know what size tires you have.

I'll check again but I think the sticker on the door specified that this pressure was for the 17inch option tire (P215 R17 Bridgestone Turanza). also, I believe the owners manual specifies recommended pressure for 16 and 17 inch but I will check again.

I emailed my local dealer about why they set my tires in the winter at 35 but now the tire that the replaced for me was set at 30 (so I had 3 tires at 35 and one at 40 until I discovered it):

"The tire pressures were probably set a bit higher because of the temp. fluctuations during the cold months and the cars sit on the lot. During colder months the tires psi decrease and the tire pressure warning system goes off. So, even though the recommended pressure is 30 psi we do set the pressures a bit higher."

[bostonsnowboarder]

Let us know your findings at 30 PSI.

with my bad back and all the pot holes we have in Boston in the spring, I like the softer ride at 30PSI better right now. The handling was more crisp at 35PSI but I can sacrifice that. Will report back on gas mileage at 30PSI after a few weeks! (just filled up my tank at $3.50/gallon - OUCH!!)

[Randy&Bonnie]

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[bostonsnowboarder]

The same size tires manufactured by different companies can have different Max PSI specifications. Tire pressure indicated on the door jam is most likely for the factory specific tires. I like my tires on the softer side, so I generally run them lower than specified. You can lose "power" through the tires (about 10 to 15%), so keeping them aired up is better for fuel mileage, but the trade-off is a rougher ride. However, with these UHP tires and softer compounds, I'm going to watch closely the wear factor and may alter the PSI based on how I see the tire wear patterns.

they might have different Max PSI specs, but do they have different minimum PSI specs?

[Tyler121]

well at my 40 psi I am averaging 22 mpg in the city. I have a 1994 so my data wont be to relevant.

[Randy&Bonnie]

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[Lexusfreak]

The same size tires manufactured by different companies can have different Max PSI specifications. Tire pressure indicated on the door jam is most likely for the factory specific tires. I like my tires on the softer side, so I generally run them lower than specified. You can lose "power" through the tires (about 10 to 15%), so keeping them aired up is better for fuel mileage, but the trade-off is a rougher ride. However, with these UHP tires and softer compounds, I'm going to watch closely the wear factor and may alter the PSI based on how I see the tire wear patterns.

You run your tires lower than what it says on the door jamb/owners manual?

And never run your tires near the max PSI it says on the sidewall (which I agree are different depending on the tire maker)......it's just asking for problems.

[Randy&Bonnie]

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[bostonsnowboarder]

The same size tires manufactured by different companies can have different Max PSI specifications. Tire pressure indicated on the door jam is most likely for the factory specific tires. I like my tires on the softer side, so I generally run them lower than specified. You can lose "power" through the tires (about 10 to 15%), so keeping them aired up is better for fuel mileage, but the trade-off is a rougher ride. However, with these UHP tires and softer compounds, I'm going to watch closely the wear factor and may alter the PSI based on how I see the tire wear patterns.

they might have different Max PSI specs, but do they have different minimum PSI specs?

Great question. Don't know. I don't recall ever seeing "minimum inflation PSI numbers". There may be some kind of weight front and rear, that is used in conjunction with the manufacturer's weight spec that the car manufacturers come up with for a PSI number for front and rear tires. B)

My understanding has been that the numbers on the door jam/owner's manual is their recommended pressure, but some also consider this number to be the MINIMUM pressure for cold inflation. Keep in mind you should always check your tire pressure cold (first thing in the morning or at least 3 hours after driving). When you drive, the pressure goes up at least 3-4 PSI.

SO, I have tended to keep my tires inflated (on any of my cars) at or slightly above the door jam PSI, and would not want to go much below it. They say that risk of premature tire failure dramatically increases if you go much below. On the other hand, I would agree that it is not a great idea to go right up to the max listed pressure on the tire side. I dont know if the max listed pressure on the tire represents a cold pressure. dont forget if you do inflate a cold pressure of the maximum number, it goes even higher when you drive!

My 05 ES330 has a door jam sticker that specifies the pressure for the 17 inch tire (P215 R17) EOM tire, which is what I have (bridgestone turanza EL42). The 05 ES came with two options, a 16 inch bridgestone or a 17 inch stock bridgestone (which is what I have). The owners manual has a seperate section for the 16 inch vs 17 inch stock tire and the recommended pressures are different. I dont know what happens if you buy another tire later.

[Lexusfreak]

My 05 ES330 has a door jam sticker that specifies the pressure for the 17 inch tire (P215 R17) EOM tire, which is what I have (bridgestone turanza EL42). The 05 ES came with two options, a 16 inch bridgestone or a 17 inch stock bridgestone (which is what I have). The owners manual has a seperate section for the 16 inch vs 17 inch stock tire and the recommended pressures are different. I dont know what happens if you buy another tire later.

I have new tires on order (New ES 350 alloys are in my basement) & will be selling my OE alloys & the Bridgestone Turanza EL42's......I will continue to keep the new rubber at the same 34 - 35 PSI (most tires in our stock 215 55 17 size have a max pressure of around 44 - 51 PSI). I have the adjustable suspension (AVS) option on my 05 ES so I can keep a good balance or ride, handling & fuel economy.

[bostonsnowboarder]

My 05 ES330 has a door jam sticker that specifies the pressure for the 17 inch tire (P215 R17) EOM tire, which is what I have (bridgestone turanza EL42). The 05 ES came with two options, a 16 inch bridgestone or a 17 inch stock bridgestone (which is what I have). The owners manual has a seperate section for the 16 inch vs 17 inch stock tire and the recommended pressures are different. I dont know what happens if you buy another tire later.

I have new tires on order (New ES 350 alloys are in my basement) & will be selling my OE alloys & the Bridgestone Turanza EL42's......I will continue to keep the new rubber at the same 34 - 35 PSI (most tires in our stock 215 55 17 size have a max pressure of around 44 - 51 PSI). I have the adjustable suspension (AVS) option on my 05 ES so I can keep a good balance or ride, handling & fuel economy.

I wish I had the AVS. Since I dont, I'll just adjust my tire pressure up and down until I get it perfect!

[bostonsnowboarder]

UPDATE:

I have monitored my fuel economy for a while with tires at both 30 PSI when cold and 35 PSI when cold. THere's only a slight difference in overall fuel economy, about 1 MPG better at 35 PSI (about 19 MPG vs 18 MPG). It is possible that if someone drove mostly highway miles the difference would be more, but I dont know as I dont get many highway miles.

However, I like the softer ride and better ride over potholes with 30 PSI. SO, I have compromised with keeping them about 32 PSI.

-BostonSnowboarder

[bmack]

I had the service shop set the tires on my 95 es300 at 32 PSI. It wasn't "cold inflation", so I guess they're actually around 29, which is slightly higher than recommended.