I like the link.
Occasionally I’ll see a kid with the newest fad, suspension extremely lowered with the wheels sticking out the wells and extreme negative camber. And I mean EXTREME. I always scratch my head wondering of they know what they’re doing to the car and the tires. Like you, I kow it’s none of my business and say nothing. I have to tell you, though, if I were doing a safety inspection there is no way I’d pass that.
@thesamemountainbike
I believe my colleagues don’t understand that they’re ruining tires by drastically overinflating them.
When I see tires like in that picture, they get replaced. And they’ll be fine until they hit a curb or get overinflated again . . .
People will do what people will do. One cannot help those who won’t be helped.
db, I did not suggest drastically over inflating the tires. I typically inflate to about 35 psi and reinflate when they get down to around 30 psi. So far I get about 100k per set of tires and the tread wears perfectly flat.
Put near maximum air in the tires, drive 55MPH, pray to your deity it will make it, and check if air filter is clean.
@andrewRA “put near maximum air in the tires” . . . ?
What the heck does that mean?
Not very specific . . .
@db4690 the maxium air I meant as maximum air pressure listed on the sidewall of the tire. This pressure is what correlates required amount for max. load capacity of the tire.
@andrewRA Question?
Are you aware that the maximum allowable pressure on the sidewall is often significantly higher than the maximum allowable pressure on the vehicle’s door jamb?
I don’t think running 5 or so PSI over the recommended inflation pressure is that big a deal and can help fuel mileage.
However, I agree that some get a bit carried away with it. Some comments by hyper-milers refer to inflating tires to 60 or so PSI to obtain better fuel economy and that’s insane IMO.
My memory is hazy on this but I seem to remember a hyper-miler stating once that he inflated all of his tires to 80 PSI. Whether he’s still alive is unknown… 
@ok4450 I certainly hope the maximum allowable pressure on the tire sidewall wasn’t 40psi
I’m not recommending tacking on 5 over the maximum sidewall pressure. In the number you provided I would not make it 45 for example.
If the tire pressure is 28 or 30, etc then bumping it up to 33 or 35 should not be an issue.
Some people will routinely inflate tires until they “look good” . . . at which point they may be extremely overinflated.
And I also know people that will inflate every single tire to the maximum allowable tire pressure on the sidewall. They will never look at the sticker on the doorjamb.
I have to disagree with andrew on the tire pressure stated on the sidewall. My understanding of this is that pressure is only listed for the tire changer. It is the maximum pressure that can be used to get the tire to seat on the bead. If the tire seats above this pressure, the momentum from seating could cause the tire to disintegrate, and under those conditions, it has known to be fatal to anyone in the area.
If the tire doesn’t seat by that pressure, the tire must be dismounted and inspected. If no defect is found, then the rim and the bead on the tire are re-lubed and inflated again. Failure to seat a second time means that the tire is defective and must be rejected. It has nothing to do with operating pressure of the tire.
The placard is the guide to use, but going 3 psi over the value on the placard is OK in most cases. In fact it is good as tires lose a little pressure over time, so that if the tires are checked every three to six months, the average tire pressure over that time will be about what is stated on the placard.
The Explorer is one of the exceptions. During the NHSTA investigation of the rollover problem, it was discovered that Ford intentionally understated the pressure in order to give the Explorer a smoother ride. A vehicle of that weight with the size tire that came on it should have been between 29 and 32 psi, but Ford recommended 26 psi. Running 32 to 35 psi for a road trip is just fine. Running 44 psi just because that is on the sidewall is NOT acceptable.
???
@keith and others…
I was under the impression that the “doorjamb” pressure was a “manufacturer’s recommendation” and NOT a limitation
(I.e. exceeding GVWR is “busting a limit” and thus illegal, but going with a different psi in the tires was not busting a limit, unless exceeding the max rating on the tire.)
I thought the “max psi” on the tire WAS for operational use, as evidenced by “max loading 4400 lbs at 42 MAX psi” (or similar.)
I’m not saying one should disregard the doorjam without due deliberation, but I never understood it to be a binding limitation.
@meanjoe75fan, consider this. The tire can be mounted to any of one hundred or more vehicles, including cars and trucks. The tire manufacturer builds the one tire for all these conditions, but only knows for certain the max design limit of the tire. The vehicle manufacturer knows the suspension, design weight, max loading, and handling characteristics of the vehicle. The placard pressure is set to ensure the tire is loaded properly and gives the best footprint and most even tire wear. It also provides for the safest operation.
@BustedKnuckles: All well and good, which is why I said, “don’t disregard without due deliberation.”
That said, at times, one’s “operational parameters” are outside of the “one size fits all” doorjam recommendation. (An excellent example would be traversing loose snow, where single-digit PSIs are typically used.)
Just saying that AFAIK, doorjam is NOT a limitation, legal or otherwise, contrary to what has been previously stated in this thread.
@meanjoe75fan, talking tire pressures on this site is very similar to talking oil changes. This topic always creates a mega-thread of so many opinions.