PDA

View Full Version : Is 42 psi right for the tires?



kinmanc
10-16-2013, 06:03 PM
I was playing with mobile app on my iPhone, and am surprised to find that 3 tires has 42 psi, and one 41 psi. Are they kinda high? My other car has only 32 psi on all tires. I just got the 500e last Saturday and those pressures were set by the dealer. What is the recommended pressure for the tires?

Tweak
10-16-2013, 07:46 PM
Welcome to the forum.

The cars ship with higher than you'd drive pressures and should but are not always adjusted by the dealer. With my Abarth it is likely different than your e so the best thing is to check the door of your driver side for the proper pressures. I have different pressures for the front and rear and since your rear tires and front tires differ slightly I suspect the same might be true of your cars requirements.

2Cool
10-16-2013, 07:59 PM
Open the driver side door, look on the rear pillar area for a sticker. It will show front and rear recommended tire pressures. For the Abarth it is 38psi front, 32 rear. The e may be different, so check first.

rcboosted
10-17-2013, 12:44 AM
I went through the same, mine was at 44psi when I checked. It should be 35psi all around. Make sure to check it when it's cold out, I did late in the evening before I went to bed. The included pump seems to read 1 PSI too high.

kinmanc
10-17-2013, 10:24 AM
I went through the same, mine was at 44psi when I checked. It should be 35psi all around. Make sure to check it when it's cold out, I did late in the evening before I went to bed. The included pump seems to read 1 PSI too high.

What included pump? You mean the tirefit kit?

Anyway, I measured pressure last night with a tire gauge, and it said 39 psi. So the reading from Fiat is a little higher. I lowered the pressure to 36 for all tires, but the reading this morning is still 42. Maybe I'll try again when the car moves.

streetsurfer
10-17-2013, 10:33 AM
Yes, it takes some time but it will reset the current pressures after the wheels have been turning.

rnddude
10-17-2013, 10:53 AM
rcboosted is correct, recommended is 35 front and rear. However, if you want to be a mpge geek, you can run them as high as 45, but the ride quality will suffer, as will the cornering grip.

Tweak
10-17-2013, 11:37 AM
Yes, it takes some time but it will reset the current pressures after the wheels have been turning.

Correct, according to the manual about 20 minutes of driving should reset things. :)

Andree
10-17-2013, 04:07 PM
Correct, according to the manual about 20 minutes of driving should reset things. :)

hahahahaha, I rarely drive for 20 minutes continuously. I bet that's why I had such problems with my tire pressure in my former car. I must have finally driven it enough for it to reset.

Andree
10-17-2013, 04:12 PM
rcboosted is correct, recommended is 35 front and rear. However, if you want to be a mpge geek, you can run them as high as 45, but the ride quality will suffer, as will the cornering grip.

Are there any hazards associated running the tires high? And shouldn't the dealer be responsible to set the tire pressure prior to selling?

rcboosted
10-17-2013, 04:30 PM
Are there any hazards associated running the tires high? And shouldn't the dealer be responsible to set the tire pressure prior to selling?

The tires are rated 44psi max(from the side wall), so I'm guessing it might be over the max when it's hot. The hazards I see are less grippy tires, (wet or dry) more wear in the center of the tire. I'm no expert, this is just some common issues with over inflated tires.

streetsurfer
10-17-2013, 04:46 PM
Wouldn't they also contribute to more easily bent (alloy) wheels when potholes or heaved joints cant be avoided? Less sidewall give transfers more energy to the wheel I suppose. You would probably have accelerated wear in the event any alignment was a bit off. Maybe some cupping on the rears from more jarring/bouncing in the ride might be a factor. Any of the suspension components would now take some of the shock that lesser inflated tires would have absorbed. Seems like that stands to reason. Correct me if I'm wrong. On the plus side, an increase in tire pressure (within reason I suppose) does help stave off hydroplaning to a degree.

kinmanc
10-17-2013, 06:19 PM
Wouldn't high pressure contributes to better mileage and range, because there is less friction on the tires?

rcboosted
10-17-2013, 06:22 PM
Wouldn't high pressure contributes to better mileage and range, because there is less friction on the tires?

yes. at the expense of traction and uneven wire wear.

SeaDawg
10-17-2013, 10:07 PM
Are there any hazards associated running the tires high? And shouldn't the dealer be responsible to set the tire pressure prior to selling?

You'd think so, but even back in May 2011 when I bought my Sport, the next morning when I checked them with my gage, they were all at 41 psi and I had wondered why the car was so squirrely on the interstate on the way home (3 hour trip). From the multitude of comments on this, it must apparently NOT be on the PDI checklist, something I, personally, find ridiculous.

SeaDawg
10-17-2013, 10:10 PM
The tires are rated 44psi max(from the side wall), so I'm guessing it might be over the max when it's hot. The hazards I see are less grippy tires, (wet or dry) more wear in the center of the tire. I'm no expert, this is just some common issues with over inflated tires.

Max inflation pressure listed on the tire sidewall is max COLD inflation pressure.

Fiat500USA
10-18-2013, 12:33 AM
You'd think so, but even back in May 2011 when I bought my Sport, the next morning when I checked them with my gage, they were all at 41 psi and I had wondered why the car was so squirrely on the interstate on the way home (3 hour trip). From the multitude of comments on this, it must apparently NOT be on the PDI checklist, something I, personally, find ridiculous.

It is on the check list; however I can see maybe why there could be a problem. The checklist consists of what to do when the car goes into lot storage and when getting the car ready for delivery. For lot storage, the tires are to be inflated to maximum sidewall pressure. When the car is delivered the pressures are to be adjusted as per the door placard. If the mechanic doesn't go down to the end of the page, he may miss this. I had to page down myself to find it as it wasn't obvious and the "Inflate tire pressure to maximum side wall pressure..." took me by surprise until I kept looking. I will mention this to someone in case people are actually missing this by accident.

Then again, sloppiness is probably the culprit in most of this.

Andree
10-18-2013, 04:05 AM
It is on the check list; however I can see maybe why there could be a problem. The checklist consists of what to do when the car goes into lot storage and when getting the car ready for delivery. For lot storage, the tires are to be inflated to maximum sidewall pressure. When the car is delivered the pressures are to be adjusted as per the door placard. If the mechanic doesn't go down to the end of the page, he may miss this. I had to page down myself to find it as it wasn't obvious and the "Inflate tire pressure to maximum side wall pressure..." took me by surprise until I kept looking. I will mention this to someone in case people are actually missing this by accident.

Then again, sloppiness is probably the culprit in most of this.

At that many dealerships? Mine was not set, and is still not set to correct driving pressure, it's still at lot storage pressure. I didn't even realize it wasn't the right pressure until one of the posts on this forum. I simply assumed the dealership was selling me a car that was as it was supposed to be. Fool that I am.

2Cool
10-18-2013, 07:23 AM
For shipment the tires start at lower than normal pressure, then after they are strapped down in the container/boat/whatever the pressure is increased to apply preload to the straps. The dealer is supposed to PDI the car before sale and set to recommended pressure. Most do not. The worst I had was when I drove my new in '04 Pontiac GTO home, it was squirrelly as hell on the interstate. Turns out it still had 60psi in every tire.

Too high of a pressure reduces handling, reduces the contact patch of the tire on the road, and creates rapid wear of the center. It also decreases ride comfort as you lose the cushion of flexing sidewalls. So don't do it. Put it to what Fiat recommends +/- 2-3psi and drive the car.

Fiat500USA
10-18-2013, 08:09 AM
It is a Federal law that there is a tire pressure placard label on the car. They are usually located inside the driver’s side doorframe or doorpost. It may also be affixed to the edge of the driver’s door or the inside of the glove-box door, trunk lid or fuel lid. depending on the year of the car and what standard was in place at the time.

Not checking the pressure at a dealership is often a sign of an inexperienced tech. Many so called easy jobs at a dealership are given out to the least experienced people so the veterans can work on the more dificult problems.

kinmanc
10-18-2013, 11:16 AM
Talking about quality of service: When I checked the tire pressure, I found out that 2 pressure valve caps were missing. It doesn't take much to replace them, but still ...