Doublebase

I run mine at 39, I'm a bit of a hypermiller. Trust me you don't want to be stuck behind me...glacier pace. My goal is to glide all the way to work (80 miles), haven't been able to do it yet, but I've come close

mckellyb

I'm just saying, I know I have a suspension problem, and it defaults to full-on "race mode", and that's likely it.

Mind you, I'm pretty okay with it being as stiff as it can be...kinda wish it were a bit stiffer, as I plan to autocross this yacht, eventually.

SW17LS

Just to other people reading the thread down the line and searching for PSI...the PSI has a huge impact on the ride comfort.

Autocrossing a LWB Lexus LS...whatever floats your boat lol

Junglequac

Amen. I just cannot get over how much of a difference it truly makes. When it was set at 40, the ride quality was downright stiff. My only justification is after having the LS430 Ultra Luxury with air shocks, I just chalked it up to the conventional suspension being more "sporty"

Bear in mind that I have not had the car that long and almost 2 weeks of which was spent getting that terrible dent fixed on the trunk followed by well over another week for a replacement brake actuator. (actually 2)

With all these issues ironed out, all that remains is for the car to be professionally detailed to at least mitigate the swirl marks endemic it seems to Obsidian Black 460's. While much better after hours of hand applying Maguire's Number 7, still not all the way there. While I have a 7 inch rotary buffer sitting there making me feel guilty and some experience on a buffer, I would feel safer in the hands of a professional as it needs to be buffed down with rubbing compound and then waxed and so forth.

SW17LS

Yeah, with the tires aired right it really rides similarly to the LS430

sapstar66

I see it a different way... my 2 gauges show me 33 while the dashboard shows 36, yes... but I see the sensors as 4 different gauges, and yet they all agree on 36. Maybe it's a different way to measure the pressure...

SW17LS

I would always trust a manual gauge over a vehicle readout. It's like hand calculating your fuel economy vs the readout, the hand calculation is more accurate.

Lexuslsguy

I always ran about 34 pounds on my 430 (17"). I run about the same on my A8 (19"). I do understand wanting a little less pressure with bigger rims to help absorb rough road. I would just say that owners should be careful to avoid over or under inflation as this will cause premature wear issue or blowing out a tire. I would not run less then 30 psi.

SW17LS

I've been running these pressures for 20k miles on the current tires and have no accelerated or unusual wear.

Even if I did, I bought this car for its ride and I want it to ride the best it can, even if it means replacing tires more often.

jmcraney

Your comment is very astute and that is the basis for my certainty that the TPMS in the LS460 displays pressures that are as accurate or more accurate than any handheld tire pressure gauge. It would not be possible to set all 5 tires to the same pressure with one handheld tire gauge and then have all five sensors report the same pressure as each other, but possibly different from the handheld gauge, without the sensors being accurate. You can extend this reasoning by considering that you can buy and introduce new sensors into the system and they will still all read the same when the tires are all set to the same pressure with an independent gauge. The only way to make this happen is accurate sensors. I have an expensive tire gauge that has 0.1 PSI resolution. I've check several LS460s and found the TPMS pressure displays to be as accurate as a 1.0 PSI-resolution display can be. The TPMS sensors are enclosed in the pressurized tire and are virtually unaffected by ambient atmospheric pressure. The TPMS design convention, which established the rules, concluded that the sensors would be affected less than 5% for any altitude variation extremes that could be encountered and decided that it would be unwise and unnecessary for the system to have atmospheric pressure compensation.

SW17LS

Here's the question for you, do the sensors read and interpret the pressure individually or do they all send data to the car's computer which then interprets that data and displays a pressure? That would explain why the pressures are even, just reporting high. The data is uniform, the computers interpretation of that data is whats at issue.

By your logic you also can't explain why two different handheld gauges also reported the same pressures, both of which are 3PSI low from the car's sensors. Two different handheld gauges that are defective in exactly the same way? Not likely.

jmcraney

Well, I'm sure the sensors measure the pressure independently and they encode it, but not encrypt it, and broadcast it, asynchronosly, via radio signal (433 MHz) to a receiver in the car which decodes it and send it to one of the cars computers which formats it and sends it to the display. Just let 5 PSI out of one of your tires, using your handheld gauge, and see what you get on the display. Did only one of the pressures change? Did one of the pressures drop 5 PSI? Because of resolution and quantization uncertainty the change could be 4 or 6 PSI instead of 5 PSI.

As to your comparison of 2 handheld gauges to one car: the comparison is 5 independent gauges in the car to 2 handheld gauges - that is a score of 5:2 in favor of the car.

Lexuslsguy

The sensors on the wheels should be quite accurate with a 1 psi range in error.

213374U

hahaha, please get someone to take video and share here. Hell, you're liable to get a good number of hits with the right title and description/keywords on YouTube as you might just be the first to do so.

roadfrog

I want to see this. I'll make some popcorn and watch it on my 75" flat screen.,