Tire pressures on SUV

[eldirector]

There is a chalk line test you can do to get a real test on it.

Highly recommend that. Chalked my little Jeep to get it to 25 PSI (oversized tires on a light-weight Jeep). On the flip side, my 3/4-ton truck calls for 60 PSI front and 70 PSI rear in Load E tires.

But, if you are running stock size and type tires, just use the recommended pressure. Easy peasy.

 

[WebSnyper]

Highly recommend that. Chalked my little Jeep to get it to 25 PSI (oversized tires on a light-weight Jeep). On the flip side, my 3/4-ton truck calls for 60 PSI front and 70 PSI rear in Load E tires.

But, if you are running stock size and type tires, just use the recommended pressure. Easy peasy.

Agreed. I should have said way too much on your average SUV.
on a big truck built for load, that would be a different story.

Oh and Discount tire will air tires and rotate (but not balance) and patch a tire if needed for free as well, even if you did not buy them there.

 

[hoosierdoc]

I saw a patient last week who had a car tire explode while airing it up. She had rubber tattooed into her face and an eye injury. Makes me nervous

 

[Old Dog]

I saw a patient last week who had a car tire explode while airing it up. She had rubber tattooed into her face and an eye injury. Makes me nervous

Wonder what PSI pressure it took to blow that tire to that extent? Would like to know if the tire was bad or more than 5 years old too. She probably had ear troubles after that also, as I expect the bang was earth shattering. Hope she will be ok.

 

[Leo]

I saw a patient last week who had a car tire explode while airing it up. She had rubber tattooed into her face and an eye injury. Makes me nervous

Tires are some thing that we would never think about a potential danger. I knew a mechanic in Lansing who lost part of his forehead and skull while airing up a wheelbarrow tire. The rim split and literally cut the top of his head off.

 

[Leo]

I had been around small capacity school buses ( I know short bus jokes ) They have high pressure tires, but I had never seen them on private SUV type cars. Evidently high pressure tires are not uncommon.

Tires 101 on Air Pressure :: Souza's Tire Service

 

[eldirector]

We had a car trailer tire blow once. It was low, so we pulled up at a truck stop. Made the mistake of using the tractor/trailer air hose. Went from 25 PSI to BOOM! in a couple of seconds. I'm guessing it had a defect, which was why it was low in the first place. Either way, scary as hell. Swear it made the trailer jump... with a vehicle ON the trailer.

I worked with a tire machine back in the day. Was taught to keep the tire/rim retained and keep your hands/face AWAY from the tire when applying air. Most folks have no idea the power behind a few PSI.

I've also reseated a tire bead with ether... so yeah, I'm that guy....

 

[femurphy77]

I've always based tire pressures on the load the tire had to support. 35ish should have been plenty for her vehicle, that's why I was asking here.

Matt

Be sure and use the proper rating tire and the proper tire pressures per the vehicle manufacturers specs. Remember back in the 90's and the rollover explorers? That was a result of dealers lowering the tire pressures on the vehicles because they rode rough with the recommended tire pressures. Under inflated tires overheat and eventually explode causing all kinds of bad things to happen directly proportional to the vehicle speed when said explosion occurs. I worked at a Goodyear plant where many of these tires came from so this is stand up advice. Or not.

 

[russc2542]

The door sticker is the #1 place to look for tire info. I wouldn't feel bad going a few psi over that but don't suggest more than +5psi without a good reason.

So the deal with the OPs situation is tire construction. As touched on before: Regular P-rated tires are half as heavy and weaker (but still more than strong enough for what's needed) but also ride a whole lot better. LT-rated tires (load range C, D, E, etc or 6, 8, 10-ply) are MUCH stronger built for heavy loads (with matching pressures!) with very stiff sidewalls, even if you lower the air pressure they'll ride a lot harsher.

Some people that think they know better than the engineers making compromises to fit the 95th percent (myself included) will sometimes choose to do otherwise to better suit their preferences or use of a vehicle based on evidence (or whimsy). Unless you you better (or think you do) your best bet when deciding on tires is to see if the vehicle calls for over 50 psi, if not, don't get LT tires. If the vehicle calls for a pressure, make sure the tires are rated for it.

Be sure and use the proper rating tire and the proper tire pressures per the vehicle manufacturers specs. Remember back in the 90's and the rollover explorers? That was a result of dealers lowering the tire pressures on the vehicles because they rode rough with the recommended tire pressures. Under inflated tires overheat and eventually explode causing all kinds of bad things to happen directly proportional to the vehicle speed when said explosion occurs. I worked at a Goodyear plant where many of these tires came from so this is stand up advice. Or not.

Yup, there were a few other things too though: the tire construction was changed at the last minute (which firestone communicated, though the communication got lost somewhere between getting to ford and trucks going out the door) and the ford engineers compromised on the design (safety vs comfort) toward comfort something like 27-28psi IIRC). AT the suggested pressure they were just barely OK with no safety margin. lose any pressure (like dealerships lowering it for comfort) and they're dangerously low.

As for tires exploding while being inflated, that tire's already been damaged somehow or is mounted wrong. The pressure on the sidewall includes working margins (inflating in the cold of winter then driving to mexico where it's 90f) or shock loads of a 6k lb SUV hitting speed bumps in the mall at 40 mph and Darwinian aspiration margins (derp thinks he'll get an extra 5mpg with 80psi in his tires...you think I'm joking but google hypermiling). Ag tires are different (FAR FAR less safety margin and construction method) and only designed for 10-15 psi.