what is the correct pressure? On the tires it says 50psi max pres. Inside the door reads 34 rear 33 front?????? sensor lite comes on and no change in pressure.

 

50 psi MAX pressure... do NOT fill it with 50. read the door jamb.

 

Yes, follow the door jamb sticker.

On my SRT6 it's 36 psi front and rear. I presume you have a 2004 or a base or limited?

 

Thanks!!! I also put new caps on my wheels. Can this cause problems with the tps

 

As previously mention... Door jamb.

When I put new shoes on my ride I had the TPMS 'rebuilt' in each wheel - it's a kit which costs only a few bucks (it may only be rubber washers etc.) - available everywhere.

You don't say when the problem started - or if it's always been there. You may have a leak somewhere (or a radish - ha ha!!!).

Easy check - remove the wheel and submerge it in the bath (obviously with water in it) - rotate the wheel and see if there's any bubbles.

 

Interesting subject....

I followed the door jamb directions on my first set of PS2s that came on the car. It had only 700 miles when I purchased it and of course the tires looked new. At roughly 12K miles the tires were nearly 75% worn out. Yes, I had taken it to a few track days, but don't feel I was particulary hard on them.

I installed a set of Nitto Invo tires same as stock size on the front and bumped to 285/30/19 at rear. Unusual tread pattern and claimed quiet ride. I read a number of reviews where people complained about excess sidewall movement. At 36PSI all around on my SRT6, I did notice some sidewall flex on cornering and it was truly uncomfortable during spirited driving. A freind who had a similar situation on another car, suggested I add 4 lb. I increased all the tires to 40 PSI and the car now tracks as if on rails. Handling is extremely precise and the the Invos still provide a relatively smooth ride, actually smoother and quieter than the PS2s at 36 PSI.

I have only had the new tires on for about 1K miles so I can't say what effect if any it has (or will have) on treadwear.

 

take 10 Psi Out Of Each Tire An Re Inflate With Correct Psi In Front/rear Drive It Will Re-cal. Did This Np. If This Doesnt Work Mite Be Issue With Rim/tire No Seal/or Tpms O Ring.

 

captjoe did you change valve stem caps? You need the metal caps on to work. The metal caps are part of the transmitting antenna, so says the manual.

When I picked up my car there was one plastic stem cap on the right front, the TPM still worked though. Had it replaced at first service.

 

On the street I usually run 33ish psi in my tires (right now I am running 34psi front and 32psi rear). When I autox or do a trackday I run considerably higher psi to prevent tire roll and to maintain a consistant temprature across the entire tread of the tire. On my 350z that equated to 44psi front and 38psi rear (hot tempratures). On my Miata it was 41psi front and 42psi rear.

I use a infared thermomiter and measure the temprature on the outside shoulder, middle, and inside shoulder of the tire after each run. All temperatures should be as close to equal as possible. If the edges are hotter than the center...you need more psi. This also helps dial in camber and a proper alignment (outside shoulder is very hot and the rest of the tire is cooler, you need more camber, inside shoulder is the hot one then you need less camber).

I haven't gotten a chance to take my xfire out autocrossing yet so I can't say what the proper psi is yet to run when driving agressively, however on a daily commute follow the door jambs.

(BTW, there's a lot more variables than this in determining the proper psi and a lot more things a tire temprature guage can tell you, but this is the basics)

 

steel caps with aluminum tps not a good idea!

 

Did you do this on the stock 9" wide rear wheel or did you get aftermarket rims too?

 

Used the stock rims. No problems. The Invo actually protects the rim bead a little even on the front. The way the PS2 fit the rim was out further than the tire.

 

Your rim size is the reason the tires felt squirmy. The tire is too large to run on a 9" wheel, Nitto recomends a 10" wide wheel with a minimum wheel size of 9.5". What happens when you put a tire on a rim too small for it is you get tire deformation. The tire would look like this:

poor_tire_pic.jpg

The tire is pinched on the wheel and it rolls around. To make it feel more stable you increase the tire pressure and then it feels right. But you have reduced traction from what the tire is capable of and it will have irregular wear.

The only size Nitto Invo that fits our wheel is the 255/35/19...stock size. But there are other manufacturers that have wider tires that will fit our 9" wheel...one of the better choices (if you want a wide tire on the stock rim) are Toyo T1R's. Their 275/35/19 fits on a 9" wheel and even has a closer rolling diameter to stock than the Nitto Invo (stock is 787 revolutions per mile, Invo is 777 revs per mile and the T1R is 782 revolutions per mile).

On top of that the T1R has been a spec tire for many racing classes (it's been proven), so you know it can hold up to the abuse of agressive track driving without blistering or seperating.

And if you increase your rear tire size you should really increase the fronts to maintain the balance the car was designed to have. A lot more traction in the rear due to (proper fitting) larger tires and then stock sized tires up front will yield more understeer. Unfortunately the only Nitto Invo that will fit our cars front is 225/40/18, again the stock size. You could go to the 245/45/18, it would fit, but the tire would be too tall and throw the traction control into fits (you are looking for a rolling diameter of 818 revs per mile up front). That Invo front has a rolling diameter of 778 revs per mile...WAY to tall. The Toyo T1R front selection however is no better than the Nitto Invo, there are wider tires that will fit, but they will be too tall.

So in the end you are left with only really the stock sizes that will work on our cars up front. (I have been looking for appropriate autox tires for the xfire for the past 3 weeks, so I have all this data at my fingertips). I have seriously looked at over 20 manufacturers and what I have seen is our front rim really limits our tire choices (on street tires).

Autox tires look a little better with Hoosier making a matching set for our car (these are full slicks however, track driving only) at 235/40/18 and 265/35/19. They comply with width and rolling diameter, and should maintain great ballance, good grip and not throw the ESP system into a fit.

All of this is completely thrown out the window however when you open yourself up to changing wheel sizes, which is why I asked.

Another thing to consider is weight, everyone thinks about lightweight wheels but nobody thinks about the weight of their tires...T1R's are widely considered the defacto standard for lightweight street tires, and our stock rear tire from them weighs 26lbs (that's heavy!!). Nitto doesn't list their weights, nor do most other manufacturers because you would be supprizingly disgusted. BF Goodwrinch g-Force™ T/AŽ KDWI is a very good tire, but probably one of the heaviest you will encounter. I know the Falken Aziena's are another great tire that will claim to be lightweight, but even they are usually several pounds heavier than the Toyo's in the same sizes.

 

Looks like I need to host that pic somewhere better....give me an hour or so and it'll be visible.

EDIT

Pic moved to photobucket for reliable hosting...

 

You don't want Hoosiers on the front for autocross (at least not in 245/35 in D stock)...cord city. Where have you seen a 235/40R18 Hoosier? I see the new 265/35R19 in the 2008 catalog (and may try it), but not that 18" size.

 

I've got to find that 235, but it was on a website and if I remember right it said "discontinued"... So I'm hoping and praying that they have it listed still because they have some left in stock... That's why I didn't list any hard numbers on that tire because I couldn't find them at the time of my post.

 

Just found this on the Hoosier site:


And I must have been smoking crack with that 235/40/18 hoosier A6...I checked all my favorites and I couldn't find the website that listed it. And I know I would have marked that site as a favorite.

 

I don't doubt anything you are saying, however with the added pressure, the car has never been more stable. To leave my neighborhood you have to get into traffic making a sharp left or right turn and stand on it. There is no signal the speed limit is 45 but most are traveling at 60-75. With my PS2s at the recommended 36, the traction control would jump in and I would have a short panic time as cars came barreling down at me. Since I put the extra 4 in the Nittos, the traction control almost never kicks in and I am up to traffic speed almost instantly.

I will check for wear regularly and if it does seem excessive I guess I will just have to get a new set of wheels. Awwww I can hear it now, "...honey I don't have a choice, I HAVE to get them..." LOL

BTW the actual amount of the tires bowing in is very little, less than 1/2" on each side. when looking at the Invos they actually look more truly straight than the PS2s did. Thos tires almost looke narrower at the tread than where the rim met (almost as if they were exactly the opposite of your drawing).

 

Hi folks; I'm new 05 Crossfire owner & Forum member appreciate the helpful info and suggestions. Am having issues w/ tire pressure sensor icon staying on. I checked pressures the are as per door pillar sticker 33# & 34#. Dealer replaced tires w/ orig sizes as part of purchase agreement now icon stays on am goin back to them tomorrow to see if the can resolve. I never thought about valve stem caps but they are all metal. will repost as soon as i know what they found out. Tony 65 yr old central Floridian and happy owner of a ride that can go around a corner, and again thanks for being there

 

question for all regarding tire pressure...

Assuming that you are putting stock tires on aftermarket rims, would the factory recommended tire pressure still applies? what about if rim size is different from stock?

someone told me it would be different... are they full of [blank]?