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Without going into a rant, can someone give me an explanation as to why tyre shops pump the tyres to some ridiculous 40+psi?
In short, I checked the pressures of my new tyres and they were 46psi warm, and 45psi cold.

I've gone through big names like Bob Jane & Beaurepaires, and smaller, private shops, and they have, almost all, done the same. The only exception being one small shop near my place, well-known to REALLY know what they are doing.

The only reasoning I can think of is that they do it because it enhances the difference between old and new.
Any other suggestions?

Cos they're slack. They like to pump them up to 40 to make sure the bead seats fully on the rim then they should back off the pressure to what suits the car, but they don't.

I've got a very seedy looking tyre shop at Moruya. Grant has done two sets for me there and they've all come back at exactly 30psi. I was shocked, I hadn't even asked him.

Ah ok, so they pump it up high so the tyre stretches and conforms to the wheel as much as possible, and they can't be f%#ked checking the pressure after the car has been dropped?
Gotcha, makes sense. Thanks Phil.

yeah they just forget sometimes.
depends on the tyre also, as prefences of the fitter will mean they put in extra psi.

I dont think I have ever had anywhere near the correct pressure in my tyres after I've had a new set fitted. They are always over inflated and quite often over the maximum pressure stamped on the tyre.

And you'll probably find the wheel nuts are on to 900000 Nm as well, as they cant be bothered torquing them properly and just rattle them on using the shop rattle gun

i'm currently in the process of having my tyre shop on. was not happy with the tyres, and with their service. got a telephone call from the tyrepower general manager of NSW yesterday, telling me he'll get to the bottom of things. so i know how you feel

I must be lucky
Over the years I have had a number of tyres fitted to a range of vehicles.
Most are supplied with between 32 to 34psi or the tyre fitter will ask what pressure I want and sets it accordingly.
Wheel nuts are a bit of hit and miss, some use a rattle gun, some use a brace and I have actually seen one use a torque wrench

If I notice they use a rattle gun to tighten the nuts, I'll ask the fitter to tighten mine with a brace.

The tyre dealer I currently use is happy to comply with my requests, therefore I will continue to use him whenever I can.

Another thing is they don't tend to use a guage in the first place, just inflate until full.

phaedo wrote:Another thing is they don't tend to use a guage in the first place, just inflate until full.

Most tyre mounting machines have the inflation hose and gauge as an integral part of the machine.

I've never had this issue.

Had my new wheels put on the other day and yep, 40psi i got them back at, plus one wheel has 70 grams of weight that are about 6 inches long!

I also now have massive vibration on the highway which has me wondering if they balanced the tyres correctly or its because they rotated them, or even worse my new wheel/s are not quite round.

Im also lacking hub centric rings which ive now ordered in the hope of making things better.

It´s done to ensure that the tyre fully seats on the rim.
If you check you´ll probably see that your manual recommends checking tyre every day or at least each week.
In any case it´s a no brainer, chck your tyre pressures with your own, reliable guage regularly and especially after anyone has fitted tyres or serviced your car, Most use inaccurate guages or dont give a rats arse

de Bounce wrote:I must be lucky
Over the years I have had a number of tyres fitted to a range of vehicles.
Most are supplied with between 32 to 34psi or the tyre fitter will ask what pressure I want and sets it accordingly.
Wheel nuts are a bit of hit and miss, some use a rattle gun, some use a brace and I have actually seen one use a torque wrench

If I notice they use a rattle gun to tighten the nuts, I'll ask the fitter to tighten mine with a brace.

The tyre dealer I currently use is happy to comply with my requests, therefore I will continue to use him whenever I can.

I have seen them use torque wrenches before....after using the rattle gun to do the nuts up. So they rattle them up tight and *click* goes the torque wrench. They assume because it has gone click that the torque is correct when in fact it is way over.

My local Bob Jane and Ian Diffen have both treated me well with service and price and done things correctly.

Besides poor education or laziness there is another reason for over tightening things and over inflating tyres. How many 'normal' motorists do you know that go and check their wheel nuts and tyre pressure once a week? Once a month? Once a year? Some people are dense enough to never check these things and then go back to the last workshop they used full of complaints when their tyres look a bit flat in 6 months or they lost a wheel after not checking for 2 years.

Talking of stupid people. Last summer I was on the freeway when a Mazda 3 overtook me.......on a space saver!! Of course a short distance later the tyre failed in spectacular fashion, I should imagine it was only pure luck or the cars inbuilt electronic aids that kept the car on the road. I am amazed that someone could be stupid enough to ignore the warnings on the wheel, tyre, handbook etc and drive a distance on the freeway at a speed far higher than the tyre is rated for.

True to form, my new set of Adrenalins were at 46psi when I got home from the tyre shop . The ride quality was aweful. Dropped them all down to 28psi. Much better!