tire pressure??

[Poseymvp]

Hi,

I read on this forum for best mileage, we should pump the tires to 39 PSI.. but will that wear out the tires faster? I'm leasing the car for 3 years/36K.. wondering if i can make the original tires last that long.. What's the optimal tire setting with best mileage is really my question..

thanks..

 

[markcmann]

Hi,

I read on this forum for best mileage, we should pump the tires to 39 PSI.. but will that wear out the tires faster? I'm leasing the car for 3 years/36K.. wondering if i can make the original tires last that long.. What's the optimal tire setting with best mileage is really my question..

thanks..

I originally had the tire pressure set to 35psi (as noted in the manual and on the car sticker) and recently increased the pressure to 39psi but honestly haven't noticed a difference in range. 4 extra pounds of pressure should not affect the wear on the tires. It was worth a try but really nothing to show for it...

 

[ecilopaveht]

I run mine at 39PSI,

The best day I have had was 6.2 Miles per kWh.

 

[iletric]

At 39 psi they heat up to about 41 in warm weather, well below max of 44 psi. The only thing happens if you overinflated is that the center tread goes out faster than the edges. You would have to be constantly at 46 psi or over for it to happen.

And yes, mileage is significanly better at 39 than 35. I see it particularly with the Leaf. ANd every time car goes to the dealer I tell them not to touch my psi. And what do they do? Bring it down to manufacturer specs. I think it's now 36 for Leaf and 35 for Spark.

 

[drchocotaco]

I've been running at 39 based on the suggestion that it improves gas mileage as well. Noticed it gets up to 42 when the weather is hot, so I've recently bumped it down to 38 just in case. Seems like my mileage has gotten a tad better, though I have also been driving slower when possible and turning off the daytime running lights and A/C when they aren't necessary. My estimated average is about 100 miles (112 to 92 spread) more or less.

 

[iletric]

My estimated average is about 100 miles (112 to 92 spread) more or less.

Very impressive. Don't worry about 42 psi in hot weather. Tires are made to take it. 38 is just fine. It's not much of a difference anyway. Try running them at 35. Then you will notice the difference in range.

Paradoxically, tires heat up more in lower psi to a point of overheating. This is particularly apparent when they're flat, like at 20 psi. You may also recall the Ford Explorer vs. Firestone tires fiasco of yesteryear as case in point.

 

[Pegasus]

Yes, the number printed on the sidewall is cold pressure, i.e. after sitting at rest for at least a couple of hours on a moderate day (70 degrees I think,) not in the sun. That number takes into account heating due to motion so you're safe to inflate to that. I check my tire pressure in the morning after they've sat overnight and it's cool outside.

I have been inflating the tires on my Prius to max spec (44 PSI in front, 42 in back) for years with no ill effects other than somewhat decreased wet grip when the tread gets low. The tread wears evenly and more slowly to boot!

 

[iletric]

I have been inflating the tires on my Prius to max spec (44 PSI in front, 42 in back) for years with no ill effects

I've done that years ago and my center tread started to wear out faster so I toned it down. Plus the lower grip is not all that pleasant.

 

[Anonymous]

I work for a heavy cargo transportation company and we are advised to make it from 40 to 42. Not to go higher to avoid risks, and not to go lower to avoid losing in speed.

 

[drchocotaco]

My estimated average is about 100 miles (112 to 92 spread) more or less.

Very impressive. Don't worry about 42 psi in hot weather. Tires are made to take it. 38 is just fine. It's not much of a difference anyway. Try running them at 35. Then you will notice the difference in range.

Paradoxically, tires heat up more in lower psi to a point of overheating. This is particularly apparent when they're flat, like at 20 psi. You may also recall the Ford Explorer vs. Firestone tires fiasco of yesteryear as case in point.

Good to know, thanks for the clarification!

I've noticed my range take a small hit the last few days, max range is now closer to 100, I'm guessing it's because I've been driving more highway miles, the efficiency takes a hit when you go over 55 mph+ from what I've read. I've also be using as a small SUV lugging building materials around, lol

 

[sspeedracer]

Set to 46 cold getting less tramlining but tends to wonder more. All expected. TPS shows as much as 49 psi on 90 degree days at 70 mph. Noticing a very mild improvement for sub 50mph trips. No noticeable miles/kw change at higher speeds. Probably not worth sacrificing performance for efficiency and lower pressure soon.

 

[buickanddeere]

Excessive pressure will tend to wear the center of the tire's tread. A greater chance of a blowout should a pothole be hit.
Run the tires at the pressure the manufacture stamped on the door sticker.

 

[sspeedracer]

Excessive pressure will tend to wear the center of the tire's tread. A greater chance of a blowout should a pothole be hit.
Run the tires at the pressure the manufacture stamped on the door sticker.

No thanks for the unsolicited advice. Do you know everything or is your life really that boring?

 

[tigger19687]

Wow, that was fresh.

I would never OVER inflate a tire for that reason and many others.

Put in what it is stated on the door.

There is talk of another Tire that works better on this Spark EV. I would look that up.

 

[iletric]

Ford Explorer/Firestone fiasco was based on the PSI door recommendation. We all, or some of us at least, remember where that ended up. (courtroom)

I run all of my tires at 5 psi below stated max for optimal mpg/mpkW. I never wear out tire treads unevenly.

 

[buickanddeere]

Excessive pressure will tend to wear the center of the tire's tread. A greater chance of a blowout should a pothole be hit.
Run the tires at the pressure the manufacture stamped on the door sticker.

No thanks for the unsolicited advice. Do you know everything or is your life really that boring?

I am probably the most boring person you will ever meet.

 

[nozferatu]

Probably +/- 2 to 3 PSI is OK...I run mine at 37 cold.