Tyre Pressure - How High Can (or Should) I Go?

[hanf]

Hi experts.

 

I drive a 7 seater Kodiaq that always has quite a lot of ‘stuff’ in it due to being a mother and also a part time childminder (think 3 / 4 baby carseats / boosters,   plus the usual wellies, waterproofs, jump leads, electric tyre pump, first aid kid, water, buggy, hat/gloves/caps, golf umbrellas, etc, etc plus of course the toddlers / tweenagers themselves.

 

Sometimes the buggy and car seats get removed but more often they stay in and are just removed for family holidays (in order to be replaced by luggage).

 

www.tyre-pressures.com says 2.4 BAR / 35 PSI for my current tyres (235/50R19 99V).    (The tyre itself says max 51 PSI)

 

Behind the fuel flap it ranges from 2.4 to 3.1 BAR from my tyre size.  3.1 is about 45 PSI?

 

I  hadn't checked the tyres since collecting 2 weeks ago so just went to check they were all on 35 as recommended but they were in fact far higher - between 37 - 40 (although obviously my digital tyre pump may not be 100% accurate).

 

So for now I’ve removed air from them all and just put them all at a 'safer' 36 PSI but I'm thinking that if it's ok to go higher I would rather do that for fuel efficiency, especially since my car is quite 'heavy' with stuff (the ride has been fine at that pressure).

But is this ok?

 

Looking at the fuel flap, I'm thinking now that I could go for a mid range 2.7 BAR / 40 PSI for all tyres?

 

This is new to me as I've always just stuck with the recommended PSI as per the door sticker for cars in the past. 

 

Any thoughts?

 

Thank you

Edited 9 April, 2022 by hanf

[hanf]

In the fuel flap picture I've just noticed that the middle section is the same as the first but just has ECO. So if this for if you are driving your car in ECO mode?

 

I'd say I'm more ECO than Sports mode these days for sure

[SurreyJohn]

Assuming you have summer tyres, there will be 3 readings on the tyre pressures chart : lightly loaded, lots of luggage and an eco setting

 

The chart is based on adults of about 70kg and something like 15kg per suitcase.  So Fully loaded with 5 adults and luggage adding about 300-400kg.   However 5 children will be about half of this so I would suggest going midway between the normal and loaded setting.

 

There really isn’t any advantage to going higher, what (very) marginal fuel saving will be more than offset in costs of maintaining the tyres because you won’t wear the tread 100% evenly if over inflated.  
 

Remember for a big heavy vehicle like this you need to be swapping the tyres front-back at intervals (the handbook suggests something like every 9000 miles), but in practice anything upto about every 14000 that fits in with when you have chance to do it (or when it is being serviced).

 

Of course if you are driving other peoples children around for a living, using summer tyres in winter is very bad idea, so just get the tyres moved when you do seasonal changes.   (Modern eco summer tyres are not designed to work in cold rain, frost, sleet, snow etc). You will either need a set of winter wheels & tyres, or dump the tyres the car came with and buy set of all season tyres, or do nothing and expect to skid or crash in winter weather.

 

Edited 9 April, 2022 by SurreyJohn

[hanf]

13 minutes ago, SurreyJohn said:

Assuming you have summer tyres, there will be 3 readings on the tyre pressures chart : lightly loaded, lots of luggage and an eco setting

 

The chart is based on adults of about 70kg and something like 15kg per suitcase.  So Fully loaded with 5 adults and luggage adding about 300-400kg.   However 5 children will be about half of this so I would suggest going midway between the normal and loaded setting.

 

There really isn’t any advantage to going higher, what (very) marginal fuel saving will be more than offset in costs of maintaining the tyres because you won’t wear the tread 100% evenly if over inflated.  
 

Remember for a big heavy vehicle like this you need to be swapping the tyres front-back at intervals (the handbook suggests something like every 9000 miles), but in practice anything upto about every 14000 that fits in with when you have chance to do it (or when it is being serviced).

 

Of course if you are driving other peoples children around for a living, using summer tyres in winter is very bad idea, so just get the tyres moved when you do seasonal changes.   (Modern eco summer tyres are not designed to work in cold rain, frost, sleet, snow etc). You will either need a set of winter wheels & tyres, or dump the tyres the car came with and buy set of all season tyres, or do nothing and expect to skid or crash in winter weather.

 

Thanks very much. I think I'll stick with the 2.4 BAR setting. Possibly going up to the 2.7 ECO option just to see if I feel any difference.

 

And thanks for the reminder about swapping the tyres over. Something my Dad always recommended.

 

And especially thanks for the tip about tyres. I thought they were all season ones but I'll check this as I certainly want to be safe. 

[Avocet]

I think SurreyJohn has covered most of it.

 

To answer your earlier question, yes 3.1 Bar is 45 PSI:

https://www.onlineconversion.com/pressure.htm

 

I would agree with John, running them harder is probably going to be a false economy because they're likely to wear out the centre of the tyre before they wear the rest of the tread area, so you'll be throwing them away earlier, and they ain't cheap!

Is yours a 4x4 version?  If so, swapping the tyres round to even out the wear is even more important.

We made (a pretty painful!) investment in a set of Winter tyres and I bought another set of second hand rims over a period of time on eBay, so we can swap them from one season to the other.  I can certainly vouch for the improvement in cold weather grip - not just snow and ice, but even just in the wet as the temperature drops below about 3 or4  degree, I can feel an improvement in stopping and cornering ability.  Supposedly, they start showing an improvement below about 7 degrees, but I can't say I've noticed it at those temperatures.  We'll swap back to the "summer" ones at the end of this month.  Beware, there's a lot of half-truth and misinformation about "winter" tyres.  Some manufacturers sell "mud-and-snow" tyres, which are NOT the same thing!  A true winter tyre will have a three-peaked mountain symbol with a snowflake in it:


if they don't have that, they don't meet the legal requirements to be a winter tyre - regardless of what's written on the sidewall!  Some all-season tyres can just about meet the winter tyre requirements, so they qualify for the symbol, others can't, so it's worth checking, and don't be fobbed off with any spiel about "mud & snow"!  (That really only refers to the tread pattern).

 

Lastly, don't be worried about tyres "bursting" if you run them at a higher pressure (obviously, within the limit marked on the sidewall)!  under-inflated tyres are at greater risk of that.  It's really only uneven wear that will be a problem. 
 

[hanf]

6 minutes ago, Avocet said:

I think SurreyJohn has covered most of it.

 

To answer your earlier question, yes 3.1 Bar is 45 PSI:

https://www.onlineconversion.com/pressure.htm

 

I would agree with John, running them harder is probably going to be a false economy because they're likely to wear out the centre of the tyre before they wear the rest of the tread area, so you'll be throwing them away earlier, and they ain't cheap!

Is yours a 4x4 version?  If so, swapping the tyres round to even out the wear is even more important.

We made (a pretty painful!) investment in a set of Winter tyres and I bought another set of second hand rims over a period of time on eBay, so we can swap them from one season to the other.  I can certainly vouch for the improvement in cold weather grip - not just snow and ice, but even just in the wet as the temperature drops below about 3 or4  degree, I can feel an improvement in stopping and cornering ability.  Supposedly, they start showing an improvement below about 7 degrees, but I can't say I've noticed it at those temperatures.  We'll swap back to the "summer" ones at the end of this month.  Beware, there's a lot of half-truth and misinformation about "winter" tyres.  Some manufacturers sell "mud-and-snow" tyres, which are NOT the same thing!  A true winter tyre will have a three-peaked mountain symbol with a snowflake in it:


if they don't have that, they don't meet the legal requirements to be a winter tyre - regardless of what's written on the sidewall!  Some all-season tyres can just about meet the winter tyre requirements, so they qualify for the symbol, others can't, so it's worth checking, and don't be fobbed off with any spiel about "mud & snow"!  (That really only refers to the tread pattern).

 

Lastly, don't be worried about tyres "bursting" if you run them at a higher pressure (obviously, within the limit marked on the sidewall)!  under-inflated tyres are at greater risk of that.  It's really only uneven wear that will be a problem. 
 

Thank you. Again, some super helpful information to act on.

In terms of swapping the tyres over. My dad was always around in the past to help me do this but sadly no more.

Is this something that a garage would do included as part of the annual service if I ask nicely? Or do I have to pay extra for this? 

[Avocet]

I'm sure they could, if you asked them!  It's a bit difficult on your own, unless you have axle stands, (or a second jack) because you need two wheels off the ground at once, really.  Also, be careful, because some tyres are directional (they'll have an arrow moulded into the sidewall saying "rotation" and showing which way they're supposed to rotate when going forwards), which means that you can swap them front-to-rear and vice-versa, but only on the same side of the car.  If you put a "left" one on the right hand side of the car, it'll be turning the wrong way.

[Yogi-Bear]

Just to add to this… I looked inside the fuel flap on mine when checking the tyres today, and there are now only 2 sets of pressures listed, one for light/normal load and one for heavy load. There is no middle ‘ECO’ option.

 

But I still pumped them up to 2.7 bar / 39 psi as I always have done on this and the previous Kodiaq. #stuckinmyways #creatureofhabit

[hanf]

1 hour ago, Yogi-Bear said:

Just to add to this… I looked inside the fuel flap on mine when checking the tyres today, and there are now only 2 sets of pressures listed, one for light/normal load and one for heavy load. There is no middle ‘ECO’ option.

 

But I still pumped them up to 2.7 bar / 39 psi as I always have done on this and the previous Kodiaq. #stuckinmyways #creatureofhabit

Thank you. That's interesting. Yes I think I'm going to stick with the 2.7 bar / 39 psi next time I pump/check the tyres. I did 2.6 / 38 psi this time and it feels fine to drive.

[SurreyJohn]

7 hours ago, hanf said:

Thank you. Again, some super helpful information to act on.

In terms of swapping the tyres over. My dad was always around in the past to help me do this but sadly no more.

Is this something that a garage would do included as part of the annual service if I ask nicely? Or do I have to pay extra for this? 

If you don’t want to swap them yourself, easiest way is either to get a garage to do it (especially if they have it for service at same time), most will charge about £20-30, but may be free if doing a job that involves taking the wheels off anyway.

 

Any tyre centre will also do swaps, and check the pressures, similar price, and if you go at quiet times they will usually do it straight away whilst you wait (the only problem with this is you have to load the tyres into the boot before you go there.

 

If picking up wheels (which can be dirty and bit bulky so not easy to carry) isn’t your thing (or you don’t have a garage or similar to store them) then find a local tyre centre that houses your seasonal tyres (they have a storage room).   Alternatively get all season tyres which can be left on all year.

 

 

[silver1011]

I tow a caravan with our Kodiaq and so increase the pressures to the maximum according to the data inside the fuel flap. Whilst towing it's fine, but when I return home and remove the caravan I'm very quickly reminded to reduce the pressures again. The car is noticeably harder on the suspension, banging in and out of the potholes and over the poor road surfaces where we live. Softening the tyres back down to normal makes a very noticeable difference to ride comfort.

[Yogi-Bear]

5 hours ago, silver1011 said:

I tow a caravan with our Kodiaq

 

Out of curiosity, how do you find towing with the 1.4TSi? I never had issues with the last bear (with same engine) when fully loaded, but my eyebrow always raises slightly when towing caravans and stuff is mentioned!

 

5 hours ago, silver1011 said:

The car is noticeably harder on the suspension, banging in and out of the potholes and over the poor road surfaces where we live. Softening the tyres back down to normal makes a very noticeable difference to ride comfort.

 

Is the suspension raised on the Scout? I never felt like it made all that much difference in the Edition.

[silver1011]

It's a difficult one, it really depends on what as an individual you deem acceptable. There are plenty of 2.0 190PS TDI and TSI owners that would like more power, and they're the type of drivers who would almost certainly find the 1.4 or 1.5 TSI lacking, even without towing.

 

Admittedly when we bought the Kodiaq I had no intention of towing, let alone a caravan, the factory towbar was simply for a bike rack. But, it tows really well. The only time it noticeably struggles is on longer motorway inclines, more so with a strong headwind, quite often a downchange to 5th is required. Other than that it performs well. I'm sure the torque of a diesel and the effortlessness of DSG would make for a better combination, but we probabaly cover less than 3,000 miles a year towing, so (at least for us) the advantages of diesel don't offset the many advantages of petrol. I've always been a fan of VAG's 1.4 150PS TSI, it's a peach of an engine and proven itself to be pretty robust too. But it definately won't suit everyone. I am a more sedate driver, no point hooning around with the kids in the car or a caravan on the back.

 

Skoda UK promoted the Scout as having increased ride height ahead of the Kodiaq's launch, but I'm not convinced it is. If it is the difference is tiny.

[Teir]

46 minutes ago, silver1011 said:

Skoda UK promoted the Scout as having increased ride height ahead of the Kodiaq's launch, but I'm not convinced it is. If it is the difference is tiny.

Apparently it has a whole 6mm of extra ground clearance! (194mm Vs 188mm). Probably not going to make too much difference going through Rufford Ford 😁

[KenONeill]

20 minutes ago, Teir said:

make too much difference going through Rufford Ford

Quote

One, two, three, another one bites the dust,...

 

[Yogi-Bear]

11 hours ago, silver1011 said:

I've always been a fan of VAG's 1.4 150PS TSI, it's a peach of an engine and proven itself to be pretty robust too.

 

I couldn't agree more... it was exceptionally nice to drive and perfectly suited to the Kodiaq.

 

I only got the vRS because I wanted a vRS... not because I wanted more power (and to be honest, the figures on the finance were actually better for me than on a 1.5 SportLine with lots of options). I'm not going to argue that the power isn't good fun at times, but given my usual journey profile, I use about 2% of the engine's power most of the time.

[silver1011]

1 hour ago, Yogi-Bear said:

I only got the vRS because I wanted a vRS...

 

And who could blame you, now the vRS is available with a petrol engine I'd argue you've now got the best of both worlds 👍

[ZacDaMan72]

22 hours ago, Yogi-Bear said:

I only got the vRS because I wanted a vRS

I only got mine because my old 190PS was too slow...

[PoloGaz]

Having run through a set of the factory kumho tyres after 25k miles on the front of mine, typically running them around 40 PSI, the tyres wore evenly across the tread.

 

I didn’t rotate them front to back like I should have, so the original rears still have lots of tread, but after 3 years the rear tyres are perished (cracking on the tread) so I need to replace them anyway

 

i have changed to Michelin primacy 4s which are meant to be good for economy, can’t say I’ve really noticed any difference so far, but I Certainly more grip than I had with the worn out Kumhos

[gumdrop]

Too hard a tyre and you will find handling changes, I usually use the ECO settings unless

I was towing andthat quite often did not need altering as long as the Noseweight was right.