Toyota recommended tire pressure vs. tire max. pressure

I understand your question, but I don't understand why you would disregard the oem recommended pressure.

If there is stated spec of torque on a bolt, would you use the max torque rated on the wrench, or the oem torque spec?

Do a little research on the Firestone/Explorer debacle.

Personally, I look at it this way... the folks that designed the vehicle doesn't have a clue what tires are going to be on it, or their recommended pressures which could range from 30 to 80PSI. I *ALWAYS* run the pressure that is on the side of the tire....max load at XX psi. In the case of the Dueler APTs that are on my Tundra, they say

44psi...so thats where I run them. It makes for better handling, better fuel economy, and more even tire wear.

Its your money, you can *DO* whatever you want.

Within reason, higher pressures won't damage your suspension. Begin by using Toyota's recommendation. Change the pressure if:

1) You have handling problems with the tires (hydroplaning, bad traction in snow). Raise pressure 2 lbs and judge the results. Don't go beyond 38-ish. If these issues continue, you have the wrong tires. 2) Uneven tire wear. Ask your mechanic if this happens. It's NOT always due to alignment problems.

Tire pressure will not damage the suspension, hill jumping in San Francisco will, crashing through the bushes with excessive speed isn't a real good thing either. Like I said before, the auto manufacturers don't have a clue what brand, size, or type of tire is going to be on the vehicle. The tire manufacturers design the tires for a specific purpose, with specific pressures, and load ratings.

Don't go beyond "38ish" even if the tires are rated at 80psi?? Wrong tires?? on a truck?? Take a close look at LT type tires... 80psi, as opposed to the passenger car tires at 32 - 44psi that most light trucks come off the showroom floor with?? WTF??? Off road tires and monster mudders run different pressures too, and so do racing tires.

Maybe your blanket tire pressure statement needs to be ammended??

Uneven tire wear could be caused by a dozen different problems.... shocks, tie rods, steering, ball joints, CV joints, bushings, bearings, oh and running the wrong tire pressures...or any combination of the above.

You are absolutely right. But, based on the messages in this, and similar newsgroups, people who ask questions here don't have a real mechanic. They have a service writer (aka "fiction writer"), or a criminal. So, in your list of things that could affect tire wear, it's a matter of luck if people here get the right thing fixed.

I have actualy inflated the tires to the OEM recommended pressure and have been using them that way, just to be safe until I determine the optimum pressure, but have been reading conflicting articles, some of which say to stick with the OEM recommendations and others which say to inflate to a higher pressure, and some which say to inflae to the max. pressure. I am just trying to get clarification.

My concerns are:

1) I want to be sure I am not under-inflating my new tires, thereby causing premature wear, and 2) The max. load on both the OEM and new tires is 2337 lbs. at the max. rated pressure. Since the OEM tires had a max. rated pressure of 35 psi, the recommended pressure of 32 psi was 91% of max. rated. The new tires have a max. rated pressure of 44 psi so by adhering to the recomended tire presure of 32 psi I am only at 73% of the max. That being the case, how will the 'actual' load capacity of the new tires be effected and will they be safe at 32 psi ? Thanks, Steve

I once got information directly from Michelin, and it differed by 2-3 pounds from what Toyota recommended. Call the tire manufacturer directly. Nobody here can give you the information you need. We can only talk in generalities.

"Steve Carr" didst type:

Maximum pressure ratings are for maximum load. My Tundra is roughly 5,000 lbs. unloaded with a payload capacity of 1,635 lbs. (4x4) so maximum load is around 6,635 lbs. Divide by four (yeah, yeah, not all wheels carry an equivalent load but this is an approximation, eh?) and you get something just shy of 1,7000 lbs.

The Revo max specs for the 265/70SR17's I run are 2,535 lbs. @ 44 psi. so even at the Tundra's maximum load capacity, the Revo's are only loaded at

75% of their maximum rating. I run 32/34 psi front/rear for comfy ride and may pressure up to 40/42 psi on long highway trips for a tad better mileage.

When running loaded with gear and pulling the trailer, I'll pressure up some too for road travel. Once the pavement ends, I'll air down to the high 20s so I don't poke a sidewall in the rocks when getting back to the campsite. Once back to the road, its back up to 32/34/38/42/whatever. I carry a 3.5 gallon tank @ 130 psi that will give me about +12 psi per tire to air back up.

Run your Revos at the OEM pressure guidelines found on the driver's side sticker with confidence and vary to taste/load with confidence.

Blah

4Runner | to replace the OEM Bridgestone Dueler H/T's. The recommended tire pressure | on the nameplate on the door of the vehicle is 32 psi. The max. cold | inflation pressure of the OEM tires was 35 psi, however, for the Revo's it | is 44 psi. I had read a Consumer Reports article which advised to stick with | the car manufacturer's recommendations for tire pressure, regardless of the | tire. I am not sure what the optimum pressure should be and I don't want to | damage my vehicle's suspension or effect its load rating. Any advice would | be appreciated. | | Thanks, | Steve | |

I read some time ago that the correct pressure is the one that gives proper contact with the pavement. I.E., too much pressure and the tire will wear out center of the tread. (Exactly what the tires were doing on the '99 Taco I bought last year) Too little and the tire will wear out the outside of the tread first. If you have to run a very low pressure to achieve the proper footprint then you need another tire sized for the weight/size of your truck.

One of the ways mentioned to determine if you have the right pressure, is to run your truck slowly through a wet spot in a straight line. Then see what the footprint looks like on the other side. Putting chalk marks across the tread is another method that has been suggested. The marks should wear off evenly when driven in a straight line.

Here is a link with pictures showing tread wear due to improper inflation:

BTW, the nameplate on my '99 Taco says 29psi for the rear and 26psi for the front. But, it also says for 225X15 tires. The truck was sold with

10.50X15 Bridgestone Duellers on it. I am running 30psi front and 28psi rear (no load) to obtain the proper footprint.

-- Jarhead

Ignore Noon-Air, he's being an ass. If you want to be truly accurate, you want to inflate the tires to the TIRE MAKER's recommended pressure for a certain load, which usually agree with the car maker's recommended pressure - but not always, see Ford Explorer debacle.

(Ford deliberately told owners to underinflate their tires to get a better ride quality, with the usual disastrous results when the tires overheated and came apart - and people got killed. IMHO, a few Ford executives and senior engineers should be serving prison sentences over that mess.)

And blindly running the Maximum Pressure on the sidewall will get you into big trouble if one end of the vehicle is lightly loaded - which is the rear tires on most front-drive small sedans, and the rarer Beetles, Porsches, Corvairs with a heavy rear bias...

A: Find out what the pressures are supposed to be B: Find out how much load is on the tires C: Adjust the pressures, then watch the tire wear

First, go to your tire dealer, and have them look up the tires you have in the catalog. There will be a Load/Pressure chart in the book for that /exact/ size, model and load-range tire.

There's also a Rubber Manufacturers Association 'generic' chart that the tire shop should have - but I've never been able to find this info online. Copy the information down, or make a photocopy of the page.

Second, go to a truck scale with the vehicle loaded as you normally drive it. Get at a minimum the axle weights at each end - you don't need individual wheel weights unless you suspect big side-to-side imbalances.

(Motorhomes get this a lot, when all the fuel & water tanks and cabinets are on one side, and the beds and dinette are on the other. Try moving the Cast Iron cookware to a cabinet on the light side.)

If you don't need a "Certified Weigh Slip" most scales will let you get the axle weights for free - or go to the Recycling Center with a load of cans and bottles, and on the way out you go over the scales slowly enough to get the axle weights going on (front) and off (rear) the scale.

Then it's a simple matter of seeing what the L/P chart says for that weight. When in doubt, go up a pound or two. Tire Pressures never leak up over time, they always leak down...

The inflation will tell over time if you have it right - if the center of the tread wears first, it's too high. Shoulders, too low.

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The MAX PRESSURE that is stamped on the tire is the max capacity of the tire in the most demanding set of operating conditions. The recommended pressure that Toyota prints on the door jamb sticker is the pressure that will give the best wear and most comfort. The two numbers have no bearing on one another.

Your tyres wearing okay? When you change em is there equal tread across the width of the tyre?

110Ks sound excessive for two and half sets. You should be getting 50Kmin each set no worries.

You will be underinflating your tires if you use the car manufacture's recommendation. That recommendation ONLY applies to tires that have the same maximum load rating (you mentioned) at 35 psi. You are corrrect in that the load rating vs tire pressure is different than for your Bridgestone tires. Either contact the tire manufacture or use the percent from maximum to calculate the correct tire pressure.

I am not sure what the optimum pressure should be and I don't want to

The reason that the Revos are stamped 44 PSI is a recent rule change for tire manufacturers. Generally, load carrying capacity increases with pressure, but tire manufacturers are permitted to mark 44 PSI inflation with the 35 PSI load. These days most tires are stamped with the 35 PSI load and 44 PSI inflation.

If you haven't changed the tire size you should stick with the placard tire pressure.