why would tire shop put 90+ psi into one of my tires?

[vash]

had a slow leak (worktruck)..i took the truck home and put the spare on. at lunch, i dropped of the tire for a patch.

that TPMS light is annoying on a chevy..it sometimes flashes, sometimes it just stays on. i get a prompt on the info screen. the shop called and i rushed down to pick it up..at the least, i figured i could put the tire in the bed JUST TO TURN OFF the tpms..

nope..i got flashing lights..and a prompt to pull over and check tire. i got home, put my gauge on it..and phrrrpp! maxed out the gauge!! wtf? i had to let out alot of air to get it down to the psi noted on the door jam.

why? this is the second time..same shop. last time all 4 new tires were ballooned to 90 psi..why?

and this shop has the low bid contract i have to use..

[Noah930]

They're idiots? It's beyond laziness. There's actually danger involved in pumping up a tire to 90 psi. To the tire guy. To whomever drives the vehicle. To the general public.

[HardDrive]

Dude...come on.....like....be cool. When I took this job, I was totally, like, told there would be no math. But this whole tire pressure thing is like mind boggling! There are like all these numbers and stuff.

[GWN7]

Call, ask manager why they are trying to kill you......

[slodave]

Don't they over inflate when putting a tire on, then back it down? Probably forgot the last step.

[mikesride]

My F250 tires run at 86lbs all the time, factory spec.

[mikester]

Maybe their gauge is broken.

[kaisen]

Originally Posted by vash

last time all 4 new tires were ballooned to 90 psi..why?

Is it a 3/4 ton or 1-ton truck? E-load range tires? Then 90 psi is okay

[EarlyPorsche]

Originally Posted by kaisen

Is it a 3/4 ton or 1-ton truck? E-load range tires? Then 90 psi is okay

No E-Load maxes out at 80psi. F load goes to 95psi.

[stomachmonkey]

So now you know to check before you leave.

Still sucks that they are stupid but you now have the knowledge to guard against it.

[vash]

Half ton truck. Tires are e rated.

[kaisen]

There are very, very few half ton trucks with factory E-load range tires. Like, 1% of all sold. So it's more likely that the heavier duty tires were added after the fact and weren't factory equipment. Therefore, the suggested pressures on the door jamb aren't going to be correct. The shop likely looked at the sidewalls and filled them to the max listed pressure in a CYA move.

[bivenator]

[
nope..i got flashing lights..and a prompt to pull over and check tire. i got home, put my gauge on it..and phrrrpp! maxed out the gauge!! wtf? i had to let out alot of air to get it down to the psi noted on the door jam.
..[/QUOTE]

Not much to add except vash's use of phrrrrp! was perfect.

[Joeaksa]

Originally Posted by mikesride

My F250 tires run at 86lbs all the time, factory spec.

Same here. Thats normal pressure for TRUCK tires...

[widgeon13]

Have you ever spent any time talking to the people that mount tires?

[lm6y]

Check the TIRE sidewall, and see what the max inflation is. If they've changed to heavier duty tires, the sticker on the door jamb will be useless. If they have changed tires, you'll be just AS dangerous by running them under inflated. Let alone fuel mileage being horrible.

[masraum]

Don't they over inflate when putting a tire on, then back it down? Probably forgot the last step.

Yep, they over inflate them initially to set the bead. I think most of the places that I've seen dip it with no valve in the valve stem. Then they*put a valve in and inflate top the proper psi. My guess is that they aren't letting the air out. I'ddefinitely call and talk to a manager, but in a nice way.

[masraum]

Check the TIRE sidewall, and see what the max inflation is. If they've changed to heavier duty tires, the sticker on the door jamb will be useless. If they have changed tires, you'll be just AS dangerous by running them under inflated. Let alone fuel mileage being horrible.

You aren't recommending setting the pressure to the max, are you. Almost every tire I've ever had on a car hashad a max up around
50 psi, but I've never run anything even remotely that high.

[Joeaksa]

Originally Posted by masraum

Yep, they over inflate them initially to set the bead. I think most of the places that I've seen dip it with no valve in the valve stem. Then they*put a valve in and inflate top the proper psi. My guess is that they aren't letting the air out. I'ddefinitely call and talk to a manager, but in a nice way.

If the vehicle has 10 ply TRUCK tires on it, any discussion with the manager will end in a difficult way. This is the NORMAL tire pressure on TRUCK tires.

[lm6y]

You aren't recommending setting the pressure to the max, are you. Almost every tire I've ever had on a car hashad a max up around
50 psi, but I've never run anything even remotely that high.

In a way, kind of. On our duallys at work we run them up to the max because they are almost always carrying a full weight load. On my personal vehicles, it's almost way over the recommendations on the vehicle placard. On the Jeep I go offroad in, it has range E tires with a max psi of 50 psi. If I were to inflate them at the 32 psi recommendation, the outside of the tires wear from underinflation, and it handles sloppy to say the least. Plus, I lose about 5 mpg. About 46 psi is the "sweet spot" for these tires, and vehicle weight. On my Grand Cherokee the tire maufacturer say a max of 44 psi, and the vehicle placard says 32 psi. 42 psi front, and around 40psi in the rear seems to be the sweet spot to keep the tires wearing evenly, and keep the mpg up. any higher, and the tires wear out the middle of the tread, and any lower, mpg goes in the tank, and the tires wear on the outside from under inflation. More and more tire companies are designing tires with higher inflation ratings to keep up with mpg demands. Most of that Firestone / Ford Explorer debacle was from under inflated tires. This is one of the BIG reasons we now have TPMS on new cars.