Hi Everyone, first post here, hopefully my question hasn't been answered a million times already. I bought a used 2007 Honda Fit a couple months ago and the previous owner had just put new tires on. Today I finally got around to checking the PSI and they were all in the 25 range. The tires say the max PSI is 51, but I think on the door it says 33. I filled them up to ~45 thinking that the rating on the door is probably for tires that come with the car. So am I safe? I'm hoping to see an uptick in MPG! Thanks in advance everyone.

 

45 might make the ride a bit bouncier, I would go with recommended pressure on door.

 

When I run 32 PSI cold (door jamb pressure) I find the tires look flat. I run 40 warm so that's about 35 PSi cold and my tires look round and they have nice traction. The ride is a bit stiffer but I like it like that.

 

45psi is perfectly fine for around town and highway driving. Your handling will suffer slightly and your tire wear might be a tad uneven, but your gas mileage will improve slightly. I personally run 40psi and see no ill effects.

15 years of driving and 10 years of autoX.

 

I would run 32PSI (cold) as the door plaque requires. This is what the Honda engineers recommend for the vehicle.

In the event you are racing or want more performance you can raise the PSI. Over inflating the tire can cause the center tread to wear faster then the shoulders just as under inflation will wear the shoulders out before the center tread.

 

We run 35 F, 31 R for the street on the Fit. (Cold inflation)


Tire inflation pressure is a compromise between rolling resistance (MPG), steering response (more PSI = quicker) and ride comfort (More PSI = hard ride). YOU have to decide what criteria pleases you the most.

The Max Inflation Pressure molded into the sidewall is a safety warning, NOT a recommendation.

I found that Low Rolling Resistance tires required a few extra PSI to maintain the previous steering response when I installed them on our CR-V.

 

Thanks for all the info! Maybe I'll see how it feels the next week or so and go from there. If the tires wear out faster then I might not really be saving any money with the improved MPG.

 

On my 08 Standard Auto, I run 36 cold on the front end and 34 cold on the back end.
No tread wear issues, and the ride is not worse than running the recommended factory pressures.
Gregg

 

Many LLR tires have a softer tire casing. This tends to create a "spongy" or "loose" steering feel. I can see why adding a few extra PSI would help some of that feel.

 

I like running 35 PSI in the front and at least 32 in the back.

 

Modern radial tires are not as susceptible to center-tread wearout as traditional tires. The belt keep the tread flat.

Proper inflation helps tire longevity by reducing failures due to excessive flexing. (Ever broken a paper clip by bending it repeatedly?) With today's short sidewalls and big rims, proper inflation also minimize the chance of rim damage.

The best practice to maximize tire life is regular rotation. I do ours every 6 - 10K miles. That gives you a chance to look at the suspension and brakes when the tires are off, too.

 

New radials are susceptible to center if over inflated. This is why car manufactures recommend a specific PSI for the vehicle. 1 or 2 PSI will not greatly affect this but 5,6, or more will make a difference.

10K for a tire rotation is too long. Many car manufactures recommend as early as 5K. The industry (tire vendors) will typically call for 7500 mile rotations. I do mine at 5K which is the same time for my oil change.

 

The 51 psi is the maximum pressure recommended by the tire manufacturer cold; the 33 psig is the recommendation from Honda for the OEM size tires. If you change size the pressure recommendation will change. Of course if you want maximum mpg and cornering 5 psii greater than Honda recommendation is a good start. Honda, like most manufacturers choose tire pressures that are comfortable to soft butts.

 

I agree with everything you say, however, on my door tag, it says 32 PSI front and rear. I run 35 cold.

 

Again if you like the stiffer feel run the 35 cold psi you were doing. The flat look is a natural look radials have at OE recommendations. I wouldn't go higher then 35psi. With the higher psi you are going to have wear issues in the long term. If you're tracking the car just bump up the air on those days.

 

i've got a '07 1.5 but have 205/45/17 setup... i use my car purely as a daily driver. what tire pressure would be the best for longevity?

 

Which is a popular size upgrade for our fits.....


I run 40 all around warm (so it that 38 cold?). I'm happy with it.

I'd like to go 45 all around but with my swift springs and NYC/NJ roads the way they are I'd likely lose a filling or a crown

funny story: I picked up my fiance's grandmother at the airport and had her in the backseat coming back from JFK to Brooklyn......Good lord she almost died back there thinking I was aiming for the potholes (calling me "Matahueco" in spanish, which translates to "pothole-killer" ) and I hit a road repair (in nyc they look like speed bumps, but are on the highway) and she hit the ceiling!!!!

I guess the swifts in the rear are strong!

 

Depending on plenty of factors, I've read that the PSI increases in a warm tyre by 4 to 6 PSI so I inflate to 5 PSI over what I want to get the appropriate cold tyre pressure. The next morning, I'll doublecheck after the car has been sitting for the whole night to see if it's right.

I inflate to 35 PSI cold. Why are you guys inflating your rear tyres less? To help with understeer?

 

The manufacturer stated PSI is based on the vehicles GWVR. It's probably the best balance of MPG, handling, comfort, etc.

I personally go a couple PSI above since I think the Fit's 32 psi is conservative. But that's just me, and I have no proof to back this up.

 

wait, so what would be the ideal cold tire pressure for a 205/45 r17 setup?