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Is it just me being old fashioned, or do recommended tyre pressures seem to be going up and up? When I used to drive old bangers I was always having to pump up tyres due to using rubbish remoulds or kerbed wheels - and most of the time you could have a guess at 28 psi as the regular pressure for most wheels and not be far off.

More recently I am seeing recommendations for 35, 38 even 40 and 42 psi for tyre pressures on MrsDibnah's Disco and my Audi.

Am I suffering some form of senile dementia or are those really high pressures in comparison to years gone by? I assume newer tyre tech, lower profiles, wider wheels etc mean that we need these sort of pressure levels - but the old air pumps at the garage forecourts still seem to default to 28-30 psi as a start range so you have to go up, up, up on the + button to get to these high numbers.
 

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The Xsara VTS I had between 2004 and 2012 used 38psi (converted from the stated bars Keithy) at the front but it had a 2.0litre lump of an engine under the bonnet. So it would seem the higher pressures have been in use for, at least, the best part of twenty years possibly because of FWD where all the mechanical gubbins is concentrated over the front wheels as well as changes in tyre design. I suspect the old less than 30psi could relate to crossply (remember them) tyres.

Just remembered; even the little 1.1 Saxo on 70 profile tyres uses 33 front and 30 rear and it is 20 years old this year
 

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Suggested pressures vary a lot depending on the car and the load (fully laden higher obvs).
I've noticed tyre fitters always seem to inflate to 33psi, so I'm guessing this is a good "safe average".
 

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39 psi for the Spider's fronts. That has to be the highest in any car I've owned.
 

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according to the handbook my 156 with 205/55/r16 should be 2.4bar (35psi) front and back with reduced load(2 occupants), 2.6 bar (38psi) front and back full load.
How many of you adjust tyre pressure when you pick up an extra passenger? :geek:

My old 7 seater Merc asks for 32 at the front and 45psi at the back with full load. I tried this once and lost a filling in my tooth.o_O
 

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according to the handbook my 156 with 205/55/r16 should be 2.4bar (35psi) front and back with reduced load(2 occupants), 2.6 bar (38psi) front and back full load.
How many of you adjust tyre pressure when you pick up an extra passenger? :geek:

My old 7 seater Merc asks for 32 at the front and 45psi at the back with full load. I tried this once and lost a filling in my tooth.o_O
:D
 

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It is down to cars getting heavier.

Also cars with run flat tyres often have very high pressures. The rear of my BMW 335i were specified at 2.9 bar. (about 43psi)
 

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2.3 bar ( i have no idea howmutch psi that is ) all around on my 159, i dont put more in the backtires.
Our 939 Spider and my old Brera, 18" and 19" wheels respectively have 2.5 rear and 2.7 bar front, as is in the hand book.
 

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So, on the sbject of tyre pressures, you put, say, 2.5bar into your tyres on a cloud covered summer day with temp of 22 C. You check the tyres in winter and the temp is 5 C, the pressures are 2.3 bar. Do you top them up to 2.5 bar? Call me old fashioned, please, but summer pressures cannot be the same as winter pressures, one is going to be wrong, and the pressures in a mild British summer will be lower that when you get to Italy with temps at 34C.
 

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So, on the sbject of tyre pressures, you put, say, 2.5bar into your tyres on a cloud covered summer day with temp of 22 C. You check the tyres in winter and the temp is 5 C, the pressures are 2.3 bar. Do you top them up to 2.5 bar? Call me old fashioned, please, but summer pressures cannot be the same as winter pressures, one is going to be wrong, and the pressures in a mild British summer will be lower that when you get to Italy with temps at 34C.
I do top mine up in winter. In fact I check the pressure every 3 to 4 months and get them bang on.
This reminds me, I need to do it the nest time I get petrol.
 

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So, on the sbject of tyre pressures, you put, say, 2.5bar into your tyres on a cloud covered summer day with temp of 22 C. You check the tyres in winter and the temp is 5 C, the pressures are 2.3 bar. Do you top them up to 2.5 bar? Call me old fashioned, please, but summer pressures cannot be the same as winter pressures, one is going to be wrong, and the pressures in a mild British summer will be lower that when you get to Italy with temps at 34C.

Yes you should adjust pressures throughout the year.
 

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I do check mine regularly…..but they will be different from one day to the next so I don't worry about it too much. Even the side parked facing the sun will have higher pressures than the other after an hour or so parked there. The pressure the factory or tyre manufacturer choses for the car is a compromise to allow for these variations. 2.5 bar all round for my 159 2.0 JTDm on factory sized 225/50-17....which is what it says the handbook. Wear and handling seem about right at that.
 

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Everytime i fill the car up with gass i fill my tires, i do it regular because of the air that escapes.
Be less hassle to just get your slow puncture(s) fixed, surely?
 
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