Newb tire question...again Tire Pressure

[SilthDraeth]

Tirerack and BF Goodrich site, as well as tire sidewall lists Max cold PSI under load as 80psi.

I checked my tires pressure (just one, and I had them put on yesterday in 107 deg heat) and it was at 38 psi. My driver side front tire looks a little less inflated than the passenger front (the one I tested).

Did the tire guys not inflate my tires fully?

Should I inflate them to 60 psi, does cold mean at 40 degrees outside, or just that I have not been driving.

Thank you.

 

[MustISO]

They should be inflated to what it says on the sticker on your driver side door (or near there).

 

[SilthDraeth]

These are not the factory tires. But basically, if the sticker says 29 psi, and the tire is rated to 80, I should still only inflate to 29?

 

[yelo333]

Cold means you haven't been driving on them. IIRC, something like "have sat for at least 3 hours without being driven for a mile."

Max sidewall is the maximum safe inflation pressure, but is probably not anywhere near optimal from a wear or handling perspective. Inflate to what the door sticker says.

 

[fstime]

If the sticker says 29, do 29, 30 or 31 wont hurt.

Always check it in the morning so the tires dont have a chance to get any heat in them and throw off the reading.

 

[Zenmervolt]

38 PSI is pretty high for a family sedan, about right for a sportscar, and not too far off for a truck. As a general rule of thumb, for a passenger car 32 PSI is generally a good setting. Obviously, the settings recommended by your car's manufacturer will be a better starting point, but you have some (maybe up to +10 PSI) of play before you get into areas where you're causing wear problems for the tires.

Do NOT inflate the tires to 80, or even 60, PSI. Since the factory recommendation is 29 PSI, 38 PSI is about as high as I would recommend going.

ZV

 

[bruceb]

Personally, I run about 3 PSI more than what the sticker on the door says.
They always make it lower than it needs to be so the ride is soft. If you want
it to handle better add the 3 PSI and see the change it makes.

 

[Billb2]

Wait, what tires are you buying that go on a car with a tire pressure rating of 29psi, but the tires are rated for 80psi?????
What car?
What tire?

 

[LTC8K6]

http://www.bfgoodrichtires.com...terrain-t-a-ko/44.html

The tire mfg can also be a lot of help in deciding on inflation pressures.

 

[SilthDraeth]

Originally posted by: Billb2
Wait, what tires are you buying that go on a car with a tire pressure rating of 29psi, but the tires are rated for 80psi?????
What car?
What tire?

06 Toyota Tacoma, sticker says 29psi. Bf Goodrich AT/KO Max PSI under load 80 psi.

LT245/75R16/E 120S RWL 10243 6.5 - 8 9.8 on 7 30.5 16 682 3042@80


I think I finally get it. The sticker is the pressure for the tire cold. Naturally while driving, and during hot weather the PSI will increase, and also the more load you put on your vehicle.

So the Tire is rated to support 3000lbs at 80psi of pressure, and if you were to inflate it cold to 80 psi the tire would explode under driving and or load.

 

[mooseracing]

Originally posted by: SilthDraeth
So the Tire is rated to support 3000lbs at 80psi of pressure, and if you were to inflate it cold to 80 psi the tire would explode under driving and or load.

The tired aren't going to explode at 80psi if thats what is on the sidewall.


The best way to determine your needs, fill the tires up to normals specs for that vehicle. Chalk a section across the tire and drive on some flat cement. Read the tread chalk pattern that was left. If the center isn't touching enough inflate it, if the outsides aren't touching enough deflate. Add in measurements of the tread blocks across the tires as you put miles on.

And don't fucking sue someone if your tire blows out, thats why there is all this stupid confusion over it. Everyone is worried about being sued. The Explorer tire lawsuit was stupid for Ford to be named in it, a vehicle does not roll instanlty on tire blow outs.

 

[jagec]

Originally posted by: mooseracing

Originally posted by: SilthDraeth
So the Tire is rated to support 3000lbs at 80psi of pressure, and if you were to inflate it cold to 80 psi the tire would explode under driving and or load.

The tired aren't going to explode at 80psi if thats what is on the sidewall.


The best way to determine your needs, fill the tires up to normals specs for that vehicle. Chalk a section across the tire and drive on some flat cement. Read the tread chalk pattern that was left. If the center isn't touching enough inflate it, if the outsides aren't touching enough deflate. Add in measurements of the tread blocks across the tires as you put miles on.

And don't fucking sue someone if your tire blows out, thats why there is all this stupid confusion over it. Everyone is worried about being sued. The Explorer tire lawsuit was stupid for Ford to be named in it, a vehicle does not roll instanlty on tire blow outs.

It was also stupid for Firestone to be named in it, since there was nothing wrong with the tires.

 

[yelo333]

Originally posted by: mooseracing

The best way to determine your needs, fill the tires up to normals specs for that vehicle. Chalk a section across the tire and drive on some flat cement. Read the tread chalk pattern that was left. If the center isn't touching enough inflate it, if the outsides aren't touching enough deflate. Add in measurements of the tread blocks across the tires as you put miles on.

Wow, this sounds like a really cool idea. I'm going to have to try this. Thanks!

 

[Black88GTA]

Originally posted by: bruceb
Personally, I run about 3 PSI more than what the sticker on the door says.
They always make it lower than it needs to be so the ride is soft. If you want
it to handle better add the 3 PSI and see the change it makes.

Higher inflation pressure will help your mpg too...

 

[OUCaptain]

Mooseracing has it right on the money if you are unsure. Tire size in relation to vehicle weight has everything to do with proper inflation. In my case on my wrangler, when I went up to 33s, I had to drop the pressure from 35 down to 25 to get the right contact patch. I'm guessing you didn't make a significant size change so I'd go with what your sticker says. And btw, 80psi is the MAX, as in damn near ready to blow. Besides, go much above 5psi more than whats correct and you'll have a bald strip down the middle within two months.

 

[radioouman]

It sounds like you put LT tires on this truck. They can handle a larger load under higher pressure, as you've already found out. But I believe that they are generally harder tires and the ride is worse.

 

[SilthDraeth]

Originally posted by: radioouman
It sounds like you put LT tires on this truck. They can handle a larger load under higher pressure, as you've already found out. But I believe that they are generally harder tires and the ride is worse.

Yes. I thought LT meant Light Truck.

 

[Zenmervolt]

Originally posted by: SilthDraeth
06 Toyota Tacoma, sticker says 29psi. Bf Goodrich AT/KO Max PSI under load 80 psi.

LT245/75R16/E 120S RWL 10243 6.5 - 8 9.8 on 7 30.5 16 682 3042@80


I think I finally get it. The sticker is the pressure for the tire cold. Naturally while driving, and during hot weather the PSI will increase, and also the more load you put on your vehicle.

So the Tire is rated to support 3000lbs at 80psi of pressure, and if you were to inflate it cold to 80 psi the tire would explode under driving and or load.

No.

The sticker pressure is for cold, up to the vehicle max capacity weight.

The pressure on the sidewall of the tire is max COLD pressure and will allow the highest load capacity of the tire. That pressure will not cause the tire to explode when driving or when under load. In fact, it will make the tire able to carry a higher load.

Blow-outs happen because of low tire pressure and resultant overheating. Tires will heat up less if you inflate them to higher pressures.

Since the tires are LT tires, they are designed to be able to be used on pickups and work vans. Work vans often inflate tires to 60 PSI or more to handle the loads they carry. Most of us aren't hauling an extra 3,000 pounds of payload every day and thus don't need tires inflated to 60-80 PSI, but LT tires are designed to handle those pressures for the specific applications that demand it.

ZV

 

[SilthDraeth]

Thank you Zen. So the standard 29 PSI is acceptable for Max pickup load, the tires are just rated to be able to handle a higher load than my truck is capable of. Thank you.

 

[Zenmervolt]

Originally posted by: SilthDraeth
Thank you Zen. So the standard 29 PSI is acceptable for Max pickup load, the tires are just rated to be able to handle a higher load than my truck is capable of. Thank you.

Just double-check your owner's manual regarding tire pressures. Sometimes a car/truck company will specify a different pressure to use when towing or hauling.

ZV

 

[Elstupido]

As a general rule you inflate the tires according to the load you will haul. the more the load the higher the inflation pressure you want to accommodate the high load, I have had good handling and wear inflating my Goodyears to around 48 psi... 55psi max for general driving with loads varying all the time.

Don't be afraid to inflate those babies to around 50psi, if rated for up to 80psi. The ride will be fine, gas mileage better, wear bettr, than if inflated to the lowest psi of around 30. Way to low, wear will be on the outside tread.

 

[Zenmervolt]

Originally posted by: Elstupido
As a general rule you inflate the tires according to the load you will haul. the more the load the higher the inflation pressure you want to accommodate the high load, I have had good handling and wear inflating my Goodyears to around 48 psi... 55psi max for general driving with loads varying all the time.

Don't be afraid to inflate those babies to around 50psi, if rated for up to 80psi. The ride will be fine, gas mileage better, wear bettr, than if inflated to the lowest psi of around 30. Way to low, wear will be on the outside tread.

*sigh*

On most cars at 50 PSI the tires will not wear better, and the ride will be awful. If you want it to ride like a delivery van and want to wear out the center of the tread, go ahead and inflate them to 20 PSI over manufacturer's recommendation.

The pressure listed in the owner's manual and on the door sticker is emphatically NOT "way to [sic] low" assuming that the OP is abiding by the load limits listed in the owner's manual.

ZV

 

[TitanDiddly]

http://www.carbibles.com/tyre_bible_pg2.html

 

[Elstupido]

OK, I think we are talking about tires under load, for which a pickup is vastly different from a passenger car. The more load you have the higher you want the inflation. That is why the 80 psi tire is rated 3000lb per tire at 80psi.. This is obviously a 6 or 8 ply tire rated for very heavy loads, which to my thinking is 12000lb gvw.

As far as I know the inflation numbers on the door are intended for the tires the vehicle came with, not all tires you may put on after.. My half ton 4x4 93 Chevy came with Goodyear Wrangler TD's and the recommended pressure on the door is 40 psi. I stuck with the TD's on my 89, 2 sets, and my 93, 4 sets. I have gotten around 35k on each set and could have run more out of them if I wasn't so dead set about not running tires into the ground.

I noticed absolutely perfect wear out them with no sings of center tread overinflation. Otherwise I would have adjusted to psi to conform with the wear. I normally have a bit of weight in the bed with my toolbox and parts bin, i woulsd say at least 600lbs. Occasionally i would load it up with 1500 to 2000lbs of copper wire or firewood. If I had 80psi tires I would pump at least 60psi into them for this kind of load. Try a 2000lb load at 29psi, and see what it drives like. On that note at 48psi I really don't notice much of a difference in ride. This is a pickup after all and not a touring sedan.

To conclude, don't believe me, but ask any qualified tire shop for proper inflation at different load conditions. Depends on your tire rating and load for a particular tire, not nec. what is on your door for a particular brand your vehicle came with new.

Don't believe

 

[Throckmorton]

Fill up to whatever the sticker says, or slightly more.