P Rock

....my tire pressure light is on (which I expected). I ordered new tires in the proper sizes to alleviate this problem but the new tires are backordered and I'll have to wait a few days. I've read that driving like this can damage the diff since it constantly thinks there's low pressure. Is there anything I can disconnect that disables the tire pressure monitors? ...or anything else that temporarily makes it ok to drive this way just for a few days. It's only temporary and I'm afraid to drive it this way in fear of damages. Any help appreciated, thanks.

BamaIS

iTrader: (3)

You aren't going to hurt anything driving it with the light on other than the annoyance from it. Did you keep your stock sensors or are you running sensors from the car the wheels came off of? If you are running different sensors you just need to go to a reputable tire store and they will have equipment to get your car to relearn the sensors.

P Rock

I assume I'm running the sensors that came with the 18's since nobody removed the sensors during the swap. The light is annoying but I'd much rather live with that than any damages to the differential.

BTW: Your cars looks great with the G 19's.

BamaIS

iTrader: (3)

You just need to have the sensors programmed. If not, when you put the new tires on you will still have a light on. Most good tire dealers can do it or you can take it to your dealership. I've heard of people getting this done at no charge at the dealership, but I've also heard of people that had to pay.

Thanks.

P Rock

So basically, it won't harm anything to run the original IS350 sizes for now? I read on here via search that it could damage the differential. Just wanted to make sure..
https://www.clublexus.com/forums/is-...-and-tmps.html

I plan to switch to 255/35/18 anyways because I don't like the bubbly look of the original 40 series on the rear.

my95tsi

iTrader: (2)

LOL...damage the differential?

Where did you hear that?

It's just a notification system that tells you your tire is low, there is no link to the differential at all. They are wireless sensors that's it, nothing magical.

If you run different sized wheels from front to rear that can damage your differential but you are running stock 18's so your fine.

my95tsi

iTrader: (2)

The other thread states this...

"Old TPMS will work fine but I wouldn't drive the car until you fix the tire size issue.

Basically your center diff thinks one set of wheels is always slipping and trying to adjust for it... good way to ruin a diff. Which on a Lexus is I'm sure a really stupid amount of money."

I think you need to read into the issue the other member was having a bit more. They are running different sized tires from front to rear to one is actually has a bigger diamter. Compeltely unrelated to the TPMS.

100degrees

iTrader: (1)

You are running different size tires and they could be ran that way only if the rolling diameter is same or very close. I ran staggered tires with the same rolling diameter on my G35X and it was ok.

P Rock

The diameters are different from frot to rear... I'm running stock sized tires for the IS350 18's which would mean the diameters from front to rear are different. Fronts are 18x8 with 225/40 and rears are 18x8.5 with 255/40. I've read I need to run 35 sidewalls in the rear to make the diameters equal to the fronts.

laobo979

iTrader: (5)

True on the tire size 255-35-18 what you need in the rear. 255-40 is not recommend on the awd cause the diameter is out of the 1% range. But the sensor warning light is nothing to worry about.

Kurtz

iTrader: (1)

To be clear- there are two totally different issues at work here:

Running different overall diameter wheel/tire combos front to back will ruin the AWD system (one can argue over how long this'll take, and how big a difference it takes, but that's quibbling- don't run significantly different diameters at all is my advice. I've seen a diff fail from a mere 50 miles of this, albeit a much older one than comes in these cars)

The TPMS is you need to get the sensors in the new wheels programmed to the car- hopefully your dealer can scan them, otherwise he'll have to remove the tires to physically read the IDs first. This part doesn't "hurt" anything though

P Rock

I guess I'm more concerned with ruining the AWD and thought the TPS light was related. Sorry for the confusion... I can deal with the light but I don't wanna deal with ruining my AWD.

Black04IS

Hey kurtz , I ve been contemplating on if i should run staggered on my AWD and I figured i would give it a try once i get correct tires. Since you seem to be one of the most knowledgeable people on here I wanted to ask for your opinion on the issue if you get the correct size. Im looking at a difference of +0.08% in the rear

Phresh2010

iTrader: (3)

i am currently running all the same tire size on my staggered is350 wheels, 225/40/18 on all four wheels, i was told this keeps the rolling diameter the same, rear tire is stretched a little bit but nothing crazy

P Rock

Phresh2010: how stretched are we talking? Do you have pics?