Tyre pressure: how high can you go?

[jpk]

How high can you inflate the tyres above the recommended 2.6 bar without triggering an alarm? Or can you set a higher pressure, say 2.8 bar, and zero it out so the car now treats that as its nominal value?

 

[fnegroni]

You can’t set the new pressure as the new ‘standard’ pressure.
The limits are fixed

 

[MoDolph]

I have mine at 2.9 bar and there is no alarm

 

[Ian Key]

The low pressure warning limit is fixed but the is no alarm for high pressure. I run my tyres at 2.6 bar

 

[jpk]

Thanks all. I'm a little surprised the system can't be reinitialised when changing the pressures but it's good to know I won't be getting bonged when I raise it to 2.8 bar ?

 

[tsedge]

Thanks all. I'm a little surprised the system can't be reinitialised when changing the pressures but it's good to know I won't be getting bonged when I raise it to 2.8 bar ?

I expect it can be changed with the right ODB2 tool, but there's certainly no user-friendly way.

 

[crl84]

I had a front-right puncture repaired a few months ago (old school push some scrap rubber into the hole and pull tool out), and the guy inflated it to 3.1 bar.
No alarms and been fine ever since, it was at 3.0 in cold weather.
All the other tyres are at 2.7/2.8.

I should probably deflate the front-right to 2.8 too, but haven't been bothered yet.

 

[MartinSEsr]

I have an SE and noticed the range (and more specifically the miles/KWh) drop as soon as it got cold. The tyre pressures also dropped, they'd been 2.6 before in the autumn, and they dropped to 2.4 when it was cold at about 5C.

After reinflating to about 2.65 bar when cold, the miles/KWh went back up almost to summer range.

I wonder how much of the reduced winter range is due to tyre pressures dropping in the cold, rather than the battery being cold? The rest of it can be explained by the heater, that uses far more power than the a/c does in the summer.

 

[Rolfe]

I have an SE and noticed the range (and more specifically the miles/KWh) drop as soon as it got cold. The tyre pressures also dropped, they'd been 2.6 before in the autumn, and they dropped to 2.4 when it was cold at about 5C.

After reinflating to about 2.65 bar when cold, the miles/KWh went back up almost to summer range.

I wonder how much of the reduced winter range is due to tyre pressures dropping in the cold, rather than the battery being cold? The rest of it can be explained by the heater, that uses far more power than the a/c does in the summer.

That's an interesting thought. I had the garage inflate all the tyres to 2.5 when they fitted the all-weather tyres in October, and I've been getting intermittent low-pressure warnings in cold weather, with one or both rear tyres showing up as 2.3.

I'm slightly tempted to try it.

 

[tsedge]

I once received a new Nissan Qashqai with the front right tyre misinflated to 5 bar. It drove fine including at motorway speeds before I checked it and corrected it.

Never had problem afterwards with the tyre and it lasted a good 25,000 miles.

 

[Ian Key]

I once received a new Nissan Qashqai with the front right tyre misinflated to 5 bar. It drove fine including at motorway speeds before I checked it and corrected it.

Never had problem afterwards with the tyre and it lasted a good 25,000 miles.

That's lorry tyre pressure.

Many years ago I was waiting to use the free air (yes it was that long ago) at my local garage and was wondering why the woman in front was taking so long to inflate her tyres so I went to see if I could help. She said the machine was only working at low pressure and she couldn't get enough air pressure into her tyre.
I had a look and she had mistaken bar for psi and was trying to inflate it to 28 bars.

 

[GarRo247]

I inflated mine to about 2.7 (on the gauge to allow for leakage taking the connector off) on one of the coldest days to get rid of the low pressure warnings. Straight away I was up to 2.8 the next day. It's been running fine at that. Anecdotal but range does seem much better. It went up as high as 3.1 on one of the warmer days so I brought it down to 2.8 ish. Now I'm between 2.6-3.0 depending on the weather. No issues so far and I'm getting over 350km if I drive carefully in urban areas with minimal heating in the SR.

 

[pmknowles]

I inflated mine to about 2.7 (on the gauge to allow for leakage taking the connector off) on one of the coldest days to get rid of the low pressure warnings. Straight away I was up to 2.8 the next day. It's been running fine at that. Anecdotal but range does seem much better. It went up as high as 3.1 on one of the warmer days so I brought it down to 2.8 ish. Now I'm between 2.6-3.0 depending on the weather. No issues so far and I'm getting over 350km if I drive carefully in urban areas with minimal heating in the SR.

The amount of air coming out when you disconnect won't affect the pressure - it takes quite a while to reduce the pressure by 0.1bar.
Driving with too high a pressure causes tyre wear in the centre of the tread which is precisely where most of the traction comes from (or grip when trying to brake). My MG4 often gives me a low pressure warning but when I check with an accurate gauge it's not.