New Z Owners - Check your tire pressure
 

Hi All,

I took delivery of my new Z on Feb 12th. Today, I checked my tire pressure for the first time (while car was cold) and found it was ~45 psig on all four tires when the recommended pressure is 35 psig (sticker inside driver's door)!! I was surprised, so I checked again with a different guage - same results. The car has been driving fine and did not really notice or suspect a problem with tire pressure. I do notice some difference now in feel and ride quality now that dropped it to 35 psig.

Maybe, it is just a one time thing, but I wanted to bring this to everyone's attention in case others have same issue. Suggest you check the pressure of your tires.

Happy Z driving...:tup:

I was thinking about the same thing. I will check the pressure now. Thanks for sharing.

I had the same problem. At first, I thought it was just because it was cold, but now that it's in the 70s, and tire pressure alarm light was still up, so I went and checked it.

Same here—all four tires at about 47psi; spare tire was at about 50psi (10psi under). I checked them all the first day we had it.

Funny you mentioned this, as i checked my tires right when i got home from the dealer and all of them were around 45psi too. I'm not sure on Nissan's logic with this as they most certainly know the recommended PSI.

tires are usually over inflated during overseas shipping to help reduce the cars moving while on the boats

Quick question, How do I know if my tires were filled with air or Nitrogen? If they were Nitrogen, do I HAVE to put nitrogen? I have no clue where the nearest Nitrogen fill up center.

kinda hard to tell....do you have green or blue valve caps thats usually a giveaway. also if you have nitrogen your pressure shouldnt go up more than maybe 2psi under normal driving. where air would go up a bit more


no you dont have to have it

I hear its really expensive to have it filled with nitrogen. It's like 30 bucks per tire. That is crazy.
A local dealership in my area (sactown/Elk grove) has a nitro filling station. I wonder how much they would charge.

Nitrogen is just a bonus gas you can put into tires that lasts longer and can give better performance due to being lighter.

Most dealerships these days have nitrogen fill stations, and have some kind of plan if you buy a new car from them. I know that the dealership that I got my Z from has some deal where they give you a free nitrogen fill up each year if you purchase the Z or a set of OEM tires from them.

All my tires were at 36psi

Isn't air 78% Nitrogen anyhow? Does it actually make that much difference?

^^^ Correct. There's no reason to fill your tires with NO2. It's really pointless... Don't pay for it. That's like filling your tires with Helium. (Stupid and wasteful)

However, depending on if you got the sport package, the tires may be rated for 45PSI for normal driving (tread ware). Most vehicle manuals will say 35PSI to be on the safe side (as most tires are rated at 35PSI), but newer tires these days are rated much higher for daily use. For track days, it's good to air them down to about 30PSI. They're perfectly safe (and definitely going to have more life) at 45PSI if you're not tracking the car.

i will give you guys one proven advantage to nitrogen i can vouch for.

under hard driving the tire pressure stays very consistant even when the tires get EXTREMELY heated. my tires are about 29PSI cold and after beating on them at autoX or a track they are only up to maybe 32 or maybe 34 in the front under really hard driving.

with air your talking alot greater fluctuations in PSI with air i would be atleast 4-5 PSI higher

LOL - maybe Nitrous (N2O) would be good for performance :) I think you meant N2 :)

MC - good point. In racing having more precise control over your tire presure is very important. I know a lot of the Sprint car guys use bleed off valves to keep the presure consistant as the tire heats up...

I put helium in my tires, reduces unsprung weight.



Yes air is about 78% nitrogen, and unless the nitrogen filling place is flushing all the air out of your tires and replacing it, I doubt you would get more than 90% pure nitrogen in your tires. If that 12% is worth it to you then by all means do it, if not... then I don't think its really a big deal.

I'll probably get nitrogen in mine because the place I buy my tires from does free nitrogen inflation.

LOL! Yeah, N2. Thanks! :D

there's a small circular sticker on my windshield by the VIN that says my tires have nitrofill--purified nitrogen. I have heard on several occasions the advantage of filling with nitrogen (like MC said: pressure doesnt change as much). At the dealership i got the Z from, its free, so I will definitely always be filling with nitrogen if i need to. Also AK, there is no problem with mixing normal air with nitrogen.

I have just checked my tire pressure. All 4 wheels 39 PSI.

sports package tires here and the tires clearly say DO NOT EXCEDE 40 PSI. i hate to say it but i am going to listen to it.

front tires 37.5, rear 38 and 39. There all set to 35.5 now, it gets cold here lately so tonight they will be at 35, will put them at 35 even in summer time.

Just a quick question to those who had high tire pressure...were your tire pressure sensors going off?

It is always a good idea to check tire pressures immediately after taking delivery of a new car. I buy cars rather frequently and have learned not to trust the dealers and in most cases find the tires to be underinflated even on the high end vehicles like Mercedes. This 370Z is the first auto where I found them all to be overinflated.

http://i576.photobucket.com/albums/s...m/DSC01415.jpg

As you can see, the tire pressures are tire (19" Sports Package Tires) specific meaning Nissan didn't just put a generic tire pressure for all the Z trims. So, I changed all 4 tires pressure to 35 PSI. :tup:

They might overpressure at the dealer to prevent the rubber from deforming permanently when the car sits on the lot. The 'rounder' the tire is, the better off it will be. Plus, they don't know when they will touch the car, or for how long it will just sit there, so they probably overpressure it so that it doesn't go flat on the lot. My dad tends to overpressure the tires on our cars when we leave them. That and hook them to trickle chargers.

35PSI is always safe. That's what I run on my car too. They may say don't exceed 40PSI because they don't know where the tires are going to be (environment-wise) so that makes sense to me. Here in Los Angeles, people run 40+ all the time.

But 35 is better for performance anyway. You get slightly better traction with 35PSI.

I just checked mine. A perfect 36.5 all the way around. I say perfect because I tend to always prefer my tires 1-2 psi above the official recommendation. Mind you, it's probably just due to a 1.5 psi variance between my pressure gauge and the dealership's.

In my case no sensors were going off, no warnings, etc. I was just checking the pressure on my daughter's car and I checked my Z. Wow... 45 psi is high!

Sounds like several had high pressure and several did not. I will check next time I take delivery of a new car.

Just checked it and it was 41psi all around. Would there be any notable damages to my tire if I drove it around at this psi for over 2 months?

no not at all. if it was super over inflated then u will see uneven wear in the tire, plus run the risk of blowing out.

Hmm, what is considered "super overinflated?" I'm guessing somewhere near 50+psi?

Exceeding the max pressure printed on the sidewall.

I'm reminded of a time when some guys were fixing bikes in my Uni dorm. One guy kept blowing inner-tubes. After the second one I heard (from my room no less) I confronted him and asked what he pressurizing them to. He said he was following the 'normal' marking on the bike pump. I looked at it and 'normal' was between 60-100 psi according to the numbers underneath the writing. I told him he was crazy for going to 60psi for a bike, but he insisted that was 'normal' like the pump said. I then looked at the side of the pump and it had RACING in big letters. Apparently Wal-Mart mountain bike/run arounds are considered racing bike now :rofl2:

He stopped pumping tires and went to fixing inner tubes.

My tires were all over 41 and the alarm was on.

tire noise?
 

I had a toyota MR2 and the prevoius owner had the tires at 45psi...when i lowered the pressure I noticed that the tires seemed a little quieter, just a thought.
Also the advantages of Nitrogen for regular street drivers is that your pressure lights won't go off every time it gets a little colder outside...really annoying..
My father raced porsches for years and they all overinflated the tires on track and slalom days to increase the grip and response, maybe nissan is doing this to increase the handling for test drives... they ran as high as 50psi without tire damage, however the tires were deflated to normal for street or storage..

I lowered the tire pressure to 35 on all tires, went for a drive to reset the warning light, but it's still on. I drove about 5 miles, stopped and cut off the engine. When I started up the car, the warning light blinks for about a minute then stays on...just what the manual says if there is a problem with the system or sensor. Guess it'll be a trip to the dealership.

Anyone else having a problem with the warning light staying on?

checked mine tonight and all were at 45 psi.

Doesn't the nitro air will last a lot longer as well? But it's really expensive isn't it?

They pick 35 because that is the compromise number. The same tire on an Infiniti they would probably pick 33 to make it a little softer. On my Infiniti I would often go to 45 psi up front during auto-x to optimize grip with all the body roll. On the street I'm usually right around 36. If it's a wet auto-x you can deflate them some for a little more predictability.

Your tire isn't going to blow out at 45, but you would be more likely to break a belt if you hit a sharp object or a large pothole. It takes about 140 psi to make a tire explode.

Just checked - 36-37 all around on mine.

The light came on for me on the way to work yesterday. Stopped and checked pressure on warmed up tires. All at 42. When I left work the light was off. Got back in later and it came off again.

Going to check pressure when cold and set to 35. If the light stays on I guess its to the dealer for me too.

LenZ - did you have to go into the dealer? Any word on what was up?