Tyres over-inflated on new vehIcle

Hedley Wright

Hedley Wright

VIP Member
Messages
189
Location
Ely
Vehicle
T6.1 Ocean 204 4 motion
Naively I assumed the tyres on my brand new Cali Ocean would be at more or less correct pressures. I have Bridgestone Weather Control A005 235/55/R17 103H XL fitted, the recommended pressure for these (full load) is 45psi front and rear.

I picked up a puncture and when I checked the tyres after having the replacement tyre fitted the other front tyre was 56psi, the rears 46.5 and 45 psi.

Don’t assume, as I stupidly did, that VW inflate to the right pressures or that they are checked by the dealer at PDI.

My ride is now more comfortable (never had a Cali before so nothing to compare with) though no doubt my excellent fuel consumption to date will rise a bit.
 
Were the tyres cold when you checked?
 
You could always get anal about it and check hot temps then adjust for cold. Pounding down a French autoroute in 38 deg will certainly produce a different pressure than static in your driveway mid December.
Measure at hot, adjust to what it should be then re check after tyres have cooled to ambient after the journey. This way you know your cold temps to set for hot conditions.

I know someone who does this! :rolleyes:
 
Measure at hot, adjust to what it should be then re check after tyres have cooled to ambient after the journey. This way you know your cold temps to set for hot conditions.
No No NO !

The pressures given in the book / on the B pillar are for Cold.

You shouldn't be adjusting them when hot as they will then be under inflated when they cool down.
 
I picked up a puncture and when I checked the tyres after having the replacement tyre fitted the other front tyre was 56psi, the rears 46.5 and 45 psi.
You could find that when cold (ambient temp typically 10 to 20 deg) 2 of those could be under inflated.
As other replies mention, check them when they are cold.
 
No No NO !

The pressures given in the book / on the B pillar are for Cold.

You shouldn't be adjusting them when hot as they will then be under inflated when they cool down.
Easy tiger, no need to have a coronary! Perfectly acceptable to adjust pressure for temperature. Basic physics.
 
You could find that when cold (ambient temp typically 10 to 20 deg) 2 of those could be under inflated.
As other replies mention, check them when they are cold.
They were checked at 9.30 a.m. I had driven about a mile and then they had stood for 45 minutes. For the purposes of checking I would consider that to be “cold”.
 
Perfectly acceptable to adjust pressure for temperature. Basic physics.

Answer is still no, the pressures given when cold take into account that the pressure is going to increase as the tyres get hot.

Basic common sense.
 
A "cold" tyre will vary in pressure by approx 10 per cent between a winter morning (0C) and a summer day (20C). And another 10-15% difference between shade and direct sunlight, independently of outside air temperature.

Personally I don't get too excited by a few psi here or there, it's going to vary anyway with time of day, season and type of journey. It's a van, we're not trying to beat lap times on the Ring.
 
A "cold" tyre will vary in pressure by approx 10 per cent between a winter morning (0C) and a summer day (20C). And another 10-15% difference between shade and direct sunlight, independently of outside air temperature.

Personally I don't get too excited by a few psi here or there, it's going to vary anyway with time of day, season and type of journey. It's a van, we're not trying to beat lap times on the Ring.
I wouldn’t get too excited by a few psi either, but that front tyre was 25% over the recommend pressure, straight from the dealer. My puncture on the other front tyre was a blowout, caused by a large flint. I have no way of knowing what the tyre pressure was but if it was similar to the other then that may have been a contributory factor. All I am saying is that it would be wise to check tyre pressures on new cars and not assume they will be correct.
 
For the past 7 +yrs with my tyres I set at 44 psi all round, during winter with ambient temperature 0-5c.
Thereafter, when I check them I ensure they are equal all round , by measuring pressures in all 4 and then setting them all to the highest pressure measured. So far they have all remained at the same pressure which varies with ambient temperature.
 
For me as a side.
However much you check them or religiously do it when they are undriven cold.
The biggest difference a few psi makes is reducing premature wear rather than safety or comfort.
My wallet doesn’t enjoy replacing tyres due to a worn strip especially if I couldn’t be bothered to check at least once a month.
I find this very worthwhile on the Cali what with the ad blue tank, fuel tank, water tanks and kitchen all on one side.
 
Last edited:
Answer is still no, the pressures given when cold take into account that the pressure is going to increase as the tyres get hot.

Basic common sense.
Agree mine rise by .4 bar at the rear and .3 bar front after about 15/20 miles in this heat and set when cold. Tried the deflation bit when hot but sets the warning symbol to activate as under inflated next day.
 
Agree mine rise by .4 bar at the rear and .3 bar front after about 15/20 miles in this heat and set when cold. Tried the deflation bit when hot but sets the warning symbol to activate as under inflated next day.
Yes the increase in pressure once run up (3-5 psi is indeed typical) is taken account of in the manufacturer's recommended cold pressure.

So,,, if after a motorway run on a hot day over the Spanish plains your tyre shows 50psi, the next morning on an early start up in the Pyrenees you might see it as low as 40psi and might well notice a bit less grip for the first few miles.

Physics, or common sense, I dunno. Except that obvs. in above scenario you won't be at risk of aquaplaning, because (All together now...)
 
We drive our 235/55/17 (Conti All Seasons) at 4.0bar // 58psi cold. I thought it was quite high, but the dealer told us it is normal. Even at long drives (which increases the temperature) and high temperatures we have no issues, although seeing 4.0bar seems over-inflated...
 
I have Tyrepal sensors fitted and pressures rise by 4psi after approx 5mls. Cold pressures vary with altitude and high and low weather barometric pressures. 3psi variation typically.
 
Picked my new Cali up last week and noticed on the TOMS that the tyres are slightly overinflated, with each tyre being different. I’m putting it down to the exceptionally hot weather we’re been having to cause this irregularity, especially if one tyre sits in full sun and the other in shade. I will check and adjust them again when when cold when the heatwave is over.
 
I had the opposite problem when collecting my T6 in March 2016. I had booked it in to get windows tinted a couple of days later and on the way a low tyre pressure warning light came on. On arrival I let the tinter know. After doing my windows he then checked all the tyres and informed me on collection that they were all at different pressures…
Not a very good PDI / safety check from dealer in my view.
 
Naively I assumed the tyres on my brand new Cali Ocean would be at more or less correct pressures. I have Bridgestone Weather Control A005 235/55/R17 103H XL fitted, the recommended pressure for these (full load) is 45psi front and rear.

I picked up a puncture and when I checked the tyres after having the replacement tyre fitted the other front tyre was 56psi, the rears 46.5 and 45 psi.

Don’t assume, as I stupidly did, that VW inflate to the right pressures or that they are checked by the dealer at PDI.

My ride is now more comfortable (never had a Cali before so nothing to compare with) though no doubt my excellent fuel consumption to date will rise a bit.
I am rapidly coming to the conclusion VW people are so unaware of practied on any vehicle they know nowt. I am thus very wary when my 6.1. is recalled because of door locks and freezing plus then they add a software update. The reality is none of them know owt. They learn on the job. Quite a worry really in reality. (I live in reality!)
 
I am rapidly coming to the conclusion VW people are so unaware or practiced on any vehicle they know nowt. I am thus very wary when my 6.1. is recalled because of door locks and freezing plus then they add a software update. The reality is none of them know owt. They learn on the job. Quite a worry really in reality. (I live in reality!)
 
I need to check back, but I had the same issue picking mine up from a commercial be dealer.

The issue I recall- two tyre types…. Garage set at a van tyre pressure, not that stated for a cali…. I can’t remember where I found this info, but was overinflated same kind of numbers and the car bounced, quite dangerously….
 
Back
Top