Tyre clearly under inflated, what would you do?

Caporegime
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During the iPod install today the dealer also gave my car a small inspection check and pointed out to me the tyre threads.

Front twos

5-6-5

Rear twos

6-7-6

Same for both, indicating 2 things.

1 - my tyres are under inflated
2 - they are well balanced and wearing evenly on all 4 lol (silver lining)

I had put all 4 tyres to 30psi about 2 months ago (new tyres was put on back in June), I remember the manual ask for 30psi for the front and 29 for the rear so i did that. or it could be the other way round but i did what the manual ask for.

So should now I inflate it to 31psi to compensate to even out the tyres for the next couple of months? Obviously will ask them to rotate them too at the next service.

This is all new to me hence i am asking :)
 
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?? forgive me here, how are they under inflated? Its normal for front tyres to wear quicker than the rears,
If anything the wear rates point to a slight over inflation
 
?? forgive me here, how are they under inflated? Its normal for front tyres to wear quicker than the rears,
If anything the wear rates point to a slight over inflation

5-6-5 (the outer wearing quicker than inner)

over inflation would mean the middle of the tyre gets most contact = less treads which would mean 5-4-5.
 
5-6-5 (the outer wearing quicker than inner)

over inflation would mean the middle of the tyre gets most contact = less treads which would mean 5-4-5.

Ah yeah, that makes perfect sense (thankyou mr 1664 :p) :o for some reason i was seeing it the other way around

Its not a massive difference and certainly nothing worth worrying about :)
 
what car and where are you pumping up? try some were else or buy a foot pump. it sould not do that with correct pressures
 
Aren't you supposed to inflate tyres when they are cold and not been driven on for a good few hours? inflating a warm tyre to the correct pressure will end up in a lower psi when it's cold. (that's my knowledge anyway :p)

Also, try checking your pressures every week or two at most, 2 months is pushing it I think!
 
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Aren't you supposed to inflate tyres when they are cold and not been driven on for a good few hours? inflating a warm tyre to the correct pressure will end up in a lower psi when it's cold. (that's my knowledge anyway :p)

Also, try checking your pressures every week or two at most, 2 months is pushing it I think!

I drove 1 mile to Sainsbury, not down the M40. lol
 
Toyota Yaris

205/45/17R

I pumped it up at Sainsbury petrol station. Preset the PSI and it stops on its own.
there is your problem, they need calibrating every now and then which never happens. same amount of wear on both tyres on the same axle proves this
 
Get a digital pressure gauge from halfords, its quite surprising how inaccurate those machines, and indeed most cheaper foot pumps are.

Those pressures seem about right for a light little car, can't remember what pressures my Yaris needs retty sure it was 30 all around and i only serviced it 2 weeks ago! Mine is a mk1 so they might be different to yours.

Plus tyres do tend to wear out slightly quicker on the outsides as they take the brunt of the cornering.
 
5-6-5 (the outer wearing quicker than inner)

over inflation would mean the middle of the tyre gets most contact = less treads which would mean 5-4-5.

Were the measurements taken from just one place on the tyre or are they an average?
There is also likely to an error of 0.5mm so your tyres could be worse or better than the figures suggest.

Personally I wouldn't worry about it. I only give my tyres a visual (pressure) check when I'm filling up with petrol. If they look under pressure I'll get out my guage and pump when it's convenient.
 
Even on a big car, my v70 is supposed to be about 30psi unlaiden, and about 34 when loaded with people luggage. You can really feel the difference at 34 if its unlaiden.

I generally have it at 32, as I prefer the feel.

what you are feeling is better pick up due to the reduced deformation of the side wall this is a trade off with braking and cornering as the tyre can not mould it self to the road serface

when I service I put inbetween unladen and laden in your case 32psi as I dont know what the owner is going to do with the car, even for the spare I would put the middle of the front and rear laden and unladen 2psi is not much to lose sleep over
 
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